JP2002032724A - An information recording medium having an optical diffraction structure, a sheet for attaching an optical diffraction structure, an optical diffraction structure transfer sheet, and a method for manufacturing an information recording medium. - Google Patents

Abstract

(57) [Summary] [PROBLEMS] A hologram seal capable of recording by laser beam irradiation, and as a result of the recording, adding more complexity and being a transparent type, so that the lower layer has a transparent property. It is an object to provide a simple light diffraction structure. SOLUTION: On card base material 2 or card base material 2
A hologram seal 6 having a structure in which a release layer 62, a hologram layer 65, a transparent light-reflective layer 66, an infrared-absorbing layer 67, an adhesive layer 68, and the like are sequentially stacked from the upper layer between b and 2a. In addition, the problem has been solved as a configuration having a recording formed on the layer 67 by a laser beam.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a transparent type light diffraction structure (typically, a hologram) in a substrate or on a substrate, and a transparent layer separate from the light diffraction structure.
The present invention relates to an information recording medium having visually recognizable information. Further, the present invention provides an information recording medium, wherein the information recording body is a card,
Further, a sheet for attaching an optical diffraction structure and a transfer sheet for an optical diffraction structure used for producing such an information recording medium and a card, and further, a production method for obtaining an information recording medium using the sheet or the transfer sheet for attachment. It is also about.

[0002]

2. Description of the Related Art Some information recording media on which various information are recorded, such as securities and vouchers, can be exchanged for money or commodities themselves, and those themselves can be exchanged. They cannot be exchanged for money or merchandise, but may be economical or otherwise costly to use if misused, such as bank or credit cards or passports. In any case, fraudulent economic benefits can be expected from `` forgeries '' that fake counterfeit products as genuine products, or `` falsifications '' such as obtaining genuine products and illegally changing the displayed contents, etc. Injustice is endless.

One of the measures against counterfeiting and alteration is
A sticky hologram is attached to the information recording medium. The reason for this is that the pattern of the hologram is precise and requires a high level of technology for manufacturing.
Normally, holograms are used as small hologram seals of the order of stamp size.

For example, a protective layer formed of an ultraviolet curable resin, a primer layer, a light diffraction structure layer (= hologram layer or diffraction grating layer), a reflection layer, and an adhesive, if necessary, are formed on a peelable substrate sheet. Using a transfer sheet in which layers and the like are laminated in order, by transfer, on a substrate such as a card, in order from top to bottom, a protective layer, a primer layer as necessary, a light diffraction structure layer, a light reflective layer, and an adhesive A hologram seal having a laminated structure in which an agent layer is laminated is applied on an appropriate substrate (Japanese Patent Laid-Open No. Hei 10-187046).

[0005] Such a hologram seal has a picture pattern recorded by a diffraction grating, and is itself very fine, and is widely used because it is difficult to forge without understanding the apparatus and manufacturing conditions. And is often used for credit cards.

[0006] However, since the method of manufacturing the hologram seal itself is known, it is possible that the hologram seal is forged, although it is difficult to forge. Also, hologram seals are commonly used by credit cards of the same company and of the same grade, and are circulated in large numbers. Therefore, if it is proof that the hologram sticker is a genuine product, obtain a credit card, peel off the hologram sticker, create it illegally, or use it The idea of sticking to the card base material arises.

[0007] On the one hand, there has been devised such that the hologram seal is broken when peeled off.
Attempts have been made to increase the complexity of the hologram seal pattern itself. Japanese Patent Publication No. 6-85102 and Japanese Patent Publication No. 6-90590 disclose another second hologram in addition to the first information possessed by the hologram. It has been proposed to provide information by processing the reflective layer. With the same intention,
0-47555 and JP-A-2000-4755.
No. 6 discloses that a pattern, a pattern, a character, an image (for example, a face photograph) other than a hologram pattern, a machine-readable barcode, an OCR character, an OMR, etc. are formed preferably by using a pulse laser. Is described.

However, in any of the above techniques,
Although it is possible to record on a metal thin film that easily absorbs laser light, the transparent reflective layer (layer having a different refractive index from the hologram layer) of the transparent hologram seal has laser light absorbency. Because there is no record
Could not be applied. In addition, the hologram seal, which uses a metal thin film as the reflective layer, inevitably hides the lower layer, so the usable size and position of the hologram are limited, and when important information is recorded, important information can be seen. It cannot be used to guarantee the authenticity of the underlying information.

[0009]

According to the present invention, recording by laser light irradiation is possible, and as a result of the recording,
It is an object of the present invention to provide an optical diffraction structure such as a hologram seal in which lower layer transparency is ensured because the structure is more complicated and transparent.

[0010]

According to our study, a light-reflective layer in a light diffraction structure such as a hologram is made to be a transparent type, and an infrared-absorbing layer is laminated and used near this layer. It has been found that the infrared absorbing layer is discolored and visible information is recorded, leading to the present invention.

According to a first aspect of the present invention, a light diffractive structure comprising at least a transparent light reflective layer and a light diffractive structure layer is embedded in a base material so as to be observable from above the base material and laminated. Laminated on a substrate, between the substrate and the light diffraction structure, or on the light diffraction structure, an infrared absorbing layer is laminated, and the infrared absorbing layer, the degree of discoloration The information recording medium is characterized in that a record composed of different areas is formed. A second invention relates to the information recording body according to the first invention, wherein further information is recorded between the base material and the light diffraction structure.
A third invention relates to the information recording body according to the first or second invention, wherein the base material has a portable card size. According to a fourth aspect of the present invention, a light diffraction structure including at least a transparent light-reflective layer and a light diffraction structure layer is laminated on a transparent substrate sheet, and between the transparent substrate sheet and the light diffraction structure, or On the light diffraction structure, an infrared absorbing layer is laminated, or on the side opposite to the side having the light diffraction structure of the transparent substrate sheet,
Alternatively, the present invention relates to a sheet for attaching a light diffraction structure, wherein an adhesive layer is laminated on a side of the light diffraction structure opposite to the transparent substrate sheet. According to a fifth aspect of the present invention, a light diffractive structure comprising at least a transparent light reflective layer and a light diffractive structure layer is laminated on the releasable surface of the peelable substrate sheet, and the releasable base of the light diffractive structure is provided. The present invention relates to a light diffraction structure transfer sheet, wherein an infrared absorbing layer is laminated on the material sheet side or on the light diffraction structure, and an adhesive layer is further laminated on the uppermost layer. According to a sixth aspect of the present invention, the sheet for attaching a light diffraction structure according to claim 4 is laminated on a substrate with the adhesive layer side facing the substrate, and thereafter, the infrared absorbing layer is irradiated with laser light. Accordingly, the present invention relates to a method for manufacturing an information recording medium, wherein a record including areas having different degrees of discoloration is formed in the infrared absorbing layer. A seventh invention forms a record comprising areas having different degrees of discoloration on the infrared-absorbing layer by irradiating the infrared-absorbing layer of the light-diffraction structure-attaching sheet according to claim 4 with laser light, Thereafter, the recorded light diffractive structure attaching sheet,
The present invention relates to a method for producing an information recording body, which comprises laminating the adhesive layer side toward a base material. According to an eighth aspect of the present invention, the transfer layer is transferred onto a base material using the light diffraction structure transfer sheet according to claim 5, and thereafter, a laser beam is applied to the infrared absorbing layer in the transferred transfer layer. The present invention relates to a method for producing an information recording medium, which comprises irradiating an infrared ray absorbing layer to form a record comprising areas having different degrees of discoloration. According to a ninth aspect of the present invention, by irradiating the infrared absorbing layer in the transfer layer of the light diffraction structure transfer sheet according to claim 5 with a laser beam, the infrared absorbing layer is recorded with areas having different degrees of discoloration. The present invention relates to a method for producing an information recording medium, wherein the method is performed by using the above-described light-diffraction structure transfer sheet on which recording has been formed, and transferring the adhesive layer side to a base material.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An information recording card according to the present invention applied to a card such as a bank card or a credit card will be described as an example. Note that the present invention is not limited to bank cards and credit cards,
The light diffraction structure will be described using an example using a hologram as a representative example, but is not limited to the hologram. In this specification, a card has a portable size of about 54 mm × 86 mm, which is industrially and commercially negotiated, and has information for performing some kind of proof function such as identification (= ID). Points to something.

In FIG. 1, an information recording card 1 is an example of a credit card.
In addition to characters such as items of expiration date, appropriate printing such as a pattern determined for each type of card 3, information unique to each card, that is, card number which is information unique to each base material , And the name of the card holder, and the embossed characters 4 formed by embossing (the expiration date itself is also formed by the embossed characters 4), and the magnetic recording layer 5 (concealed by a concealed layer so as not to be seen). Is formed, and the information recording card 1 has a hologram seal 6 attached thereto for ensuring that the information recording card 1 is genuine and for preventing forgery.

A print 3, an embossed character 4, and a magnetic recording layer 5 are usually provided in the case of a credit card. It is not necessary to arrange all of them, but considering the function of the current card, the minimum
Should be provided. Of course, an IC module and / or an optical recording layer may be provided instead of the magnetic recording layer 5, and two or three of the magnetic recording layer, the IC module and the optical recording layer may be provided. Good.

[0015] Logos and pictures such as card names for distinguishing cards issued from the same credit company of various types have lower priority than the magnetic recording layer and the IC module, but are provided in practical use. And for credit card applications, it should have embossed characters that may actually be used.

FIG. 2 is a cross-sectional view of the information recording card 1 shown in FIG. 1 taken along a line AA in the left-right direction to show the laminated state of the hologram seal. The hologram seal 6 is laminated on the card base material 2 of the information recording card 1 in FIG. 2A, and the hologram seal 6 is manufactured by applying the hologram seal 6 to the surface of the half-finished card by transfer. It is a form. On the other hand, the information recording card 1 in FIG. 2 (b) has a transparent sheet 2a called an oversheet as the uppermost layer of the card base material 2, under which a core sheet 2b is laminated. The seal 6 is laminated between the core sheet 2b and the oversheet 2a. In this embodiment, the hologram seal 6 is previously attached to either the core sheet 2b or the oversheet 2a in the process of forming the card base material, or the hologram seal 6 is attached to the core sheet 2b and the oversheet 2a.
The hologram seal is applied depending on whether the hologram seal 6 is interposed when a is attached.

Actually, even in the case shown in FIG. 2A, the card base material 2 is composed of an oversheet, two core sheets, and an oversheet in a total order of 4 from the top.
In many cases, a laminate of two sheets is used. Even in the case shown in FIG. 2B, another core sheet is provided below the core sheet 2b, and another oversheet is further provided thereunder. Are usually laminated to form a laminate of a total of four sheets.

The hologram seal 6 has an overall thickness of 8 in consideration of being used for an information recording card.
It is preferably formed to have a thickness of at most 6 μm, more preferably at most 6 μm.

Incidentally, the hologram seal 6 in the present invention is a so-called transparent hologram laminated with an infrared absorbing layer. 3 (a) to 3 (d) are diagrams each showing a main part of the hologram seal 6. For example, the one shown in FIG. 3 (a) is a hologram layer in which hologram irregularities are formed on the lower surface from above. 65, a transparent light-reflective layer 66, an infrared-absorbing layer 67, and an adhesive layer 68 formed along the hologram irregularities of the hologram layer 65 are sequentially laminated.
Has a record 67a formed by a change such as discoloration.

In the hologram seal 6, a transparent light-reflective layer 66 needs to be laminated on the uneven surface of the hologram layer 65. Either layer may be on the observation side or the back side. The absorption layer 67 includes the hologram layer 6
3B and the transparent light-reflective layer 66 may be on the observation side or the back side of the laminate, and variations shown in FIGS. 3B to 3D are possible. It should be noted that the adhesive layer 68 is laminated on the lowermost layer because it is necessary to adhere to the adherend.

In FIG. 3B, FIG.
The infrared absorbing layer 67 of FIG.
5 corresponds to the one moved to the upper side. 3 (c) and 3 (d), the hologram layer 65 and the transparent light-reflective layer 66 are arranged in the reverse order of those shown in FIGS. As shown in FIG. 3C, the infrared absorbing layer 6 was placed on the observation side of the laminate in which the layer 67 and the hologram layer 66 were sequentially laminated.
7 are laminated, and those in which an infrared absorbing layer 67 is laminated on the back side of these laminates. FIG.
In any of (b) to (d), a record 67a is formed on the infrared absorbing layer 67 due to a change such as discoloration.

Incidentally, the infrared absorbing layer 67 is formed as shown in FIG.
In the examples shown in (d), it is described that the hologram layer 65 or the transparent light-reflective layer 66 is directly laminated on the hologram layer 65 or the transparent light-reflective layer 66. The laminated body A or the laminated body B in which the transparent reflective layer 67 and the hologram layer 66 are laminated in order from the observation side may not directly overlap with each other. Another layer may be interposed between A and B.

Further, even if the infrared absorbing layer 67 is not formed as a separate layer, the adhesive layer 68 can also serve as an infrared absorbing layer by making the adhesive layer 68 infrared absorbing. In the following, the description regarding the recording using the infrared absorbing layer also applies to the adhesive layer also serving as the infrared absorbing layer.

FIG. 4A shows an example in which the present invention is applied particularly to the hologram seal 6. In FIG. 4A, a vertically long rectangular hologram seal 6 has a hologram image 7 (hologram image itself is not shown) formed over the entire area surrounded by a surrounding frame line, and the center is slightly upward. Is formed in the area 8 where the recording is formed on the infrared absorbing layer.

4A, information 9 associated with information unique to each base material 2 of the information recording card 1 is provided below the hologram seal 6 in the infrared absorbing layer of the hologram seal 6. The recording is formed by using the. In the illustrated example, the information 9 is the same as the credit card number represented by the embossed characters 4 on the base material 2 and the name of the card holder. Further, above the right side of the hologram seal 6, a serial number for manufacturing the hologram seal 6, that is, information 10 unique to one hologram seal is provided.
Are recorded and formed by using the infrared absorbing layer of the hologram seal 6.

FIG. 4B shows an example of a hologram sign panel in which the present invention is applied not to the hologram seal 6 but to a sign panel often provided on the back of a credit card or the back of a bank card. It is. Therefore, in one information recording card 1, the one shown in FIG. 4A and the one shown in FIG. 4B may be laminated on the front and back of the information recording card 1. In FIG. 4B, the horizontally long hologram sign panel 11 has a basic structure
Similarly to the hologram seal shown in FIG. 4A, a hologram image 12 (hologram image itself is not shown) is formed in the entire region surrounded by a frame line around the hologram seal. The cardholder's own signature 13
The difference is that the recording is performed by using the infrared absorbing layer of the hologram seal 6.

In a bank card, a credit card, or the like, if the signature 13 is formed only on the signature panel 11, the character of the signature 13 is information unique to one hologram seal. If there is still another signature panel with a handwritten signature, the signature 13 recorded and formed by using the infrared absorbing layer of the hologram seal 6 is applied to each base material 2 of the information recording card 1. It can be said that the information is associated with the unique information.

In the above, the formation of information recording on the infrared absorbing layer is performed by partially removing the infrared absorbing layer by a thermal, chemical, or mechanical method, and partially deforming the infrared absorbing layer. Causing a partial color change of the infrared absorbing layer, partially changing the structure of the infrared absorbing layer, and thermally changing the phase, partially changing the polarization characteristics of the infrared absorbing layer (magneto-optical method) The method can be performed by partially forming the infrared absorbing layer by performing metal deposition or the like through a partial mask, or by partially replacing the material of the infrared absorbing layer. In order to record information by changing the infrared absorbing layer, any of the above-mentioned methods may be used. However, it is preferable to use a thermal method that can perform recording with a small number of steps and causes a visual change.

Examples of the thermal recording method include a method using a thermal head, a method using infrared flash exposure, and a method using laser light. Above all, laser light is excellent because it has good energy efficiency and can be scanned.
When a pulse laser beam is used as the laser beam, a high output can be obtained only for a very short time, so that there is no adverse effect on the base material and other layers, which is preferable. In particular, in a recording method using a laser beam, for example, halftone dots and lines can be formed at a pitch of 10 μm, and a very precise image can be formed. =
(Gradation image) can also be formed, so that there is an advantage that a face photograph can be created with high accuracy. Further, in the recording method using laser light, the laser light irradiated portion has a relatively light colored state (for example, yellow), and therefore, there is an advantage that the portion discolored by irradiation does not hinder the visibility of the lower layer.

In the above, the pulse laser light is
A method of controlling the output of CW laser light (continuous light) by an external modulator, or inserting a Q switch into a laser resonator and switching the Q switch to instantaneously output the energy stored in the laser medium. There is a way. As continuous laser light, there are an argon laser, a He-Ne laser, a YAG laser, a semiconductor laser, and the like. As an external modulator, a mechanical shutter, an A / O modulation element, an E / O modulation element, or the like is combined with a Q switch. And by controlling the Q value of the resonator, pulsed light having a time width of several tens to several hundreds of nanoseconds can be generated.

The information recorded by the change in the infrared absorbing layer as described above is not recorded / reproduced with respect to the amplitude and phase of the light wave like a hologram, but only the amplitude and / or wavelength of the light wave. Is recorded / reproduced.

The information recorded by the change of the infrared absorbing layer includes, for example, the card number of the credit card or the attribute number such as the name, the number of a gift certificate or a ticket in a gift certificate, and the like. The information of these numbers is usually also recorded on the card base material, and is information unique to one card base material, so long as the information is associated with the information unique to each card base material. It is preferred that Note that “associated” does not necessarily mean that the numbers are the same,
Including appropriate numbers, characters, and the like that are visually different by appropriate conversion, encryption, and the like, it is only necessary to correspond to 1: 1.

The information recorded by the change of the infrared absorbing layer includes attribute data such as a photograph, a fingerprint or a signature, or manufacturing data such as a manufacturing date, a manufacturing place, and a manufacturing lot number, in addition to the above. , These data
If it is recorded on both the card substrate and the hologram seal,
It becomes information associated with unique information for each card base material, but when recorded only on the hologram seal,
Information is unique for each light diffraction structure (hologram in this case). Of course, the information recorded by the change in the light reflective layer may be a company name or a card name that does not necessarily require security, or other information.

Regardless of the type of information, numerical and character information is recorded in a normal form and can be visually recognized. In addition, a machine-readable form such as a bar code, OCR characters, Alternatively, the information may be recorded in a form that can be read by both humans and machines, such as OMR characters. Further, the recording may be not only information recorded ON / OFF, but also information recorded in gray scale.

As exemplified in FIG. 4, two types of information, that is, information associated with information unique to each card base material and information unique to each light diffraction structure are used in the present invention. In either case, either one type of information may be recorded or both types of information may be recorded, but when only one type of information is recorded, the former, one card base Recording information associated with information unique to each material provides higher security.

Next, with reference to FIGS. 5 (a) and 5 (b), an information recording card which is close to the form actually embodied will be described. The information recording card 1 shown in FIG.
And a hologram seal 6 is laminated on the card base material 2. The hologram seal 6 has a release layer 62 from above and a hologram layer having hologram irregularities on the lower surface ( Light diffraction structure layer) 65,
It has a structure in which a transparent light reflective layer 66, an infrared absorbing layer 67, and an adhesive layer 68 are sequentially laminated, and the infrared absorbing layer 67 has a record 67a due to a change such as discoloration.

The information recording card 1 shown in FIG. 5 (b) corresponds to the information recording card 1 shown in FIG. 2 (b), and the card base is composed of a core sheet 2b and an oversheet 2a. 5 (a), a release layer 62 from the upper side, a hologram layer (one of the light diffraction structure layers) 65 having a hologram unevenness on the lower surface, a transparent light reflective layer 66,
The hologram seal 6 has a structure in which the infrared absorbing layer 67 and the adhesive layer 68 are sequentially laminated, and the hologram seal 6 having the infrared absorbing layer 67 and the recording 67a due to a change in discoloration or the like is formed between the core sheet 2b and the oversheet 2a. They are laminated between them.

Actually, as described above, the card base material is a laminate of a total of four sheets of an oversheet, two core sheets, and an oversheet in order from the top. Often. The hologram seal 6 shown in FIGS. 5A and 5B is a representative example, and has a different structure as described with reference to FIGS. 3A to 3D. Can be replaced.

It should be noted that another layer is formed in the hologram seal 6, another information is recorded, and further forgery /
The difficulty of alteration can be increased. For example, a dye image formed by forming a dye receptive layer and transferring a sublimable dye or a pigment image formed by attaching a pigment and a binder resin can be formed.

The contents of each of the above-described layers will be described. The release layer 62 is laminated on the uppermost layer after the transfer when the hologram seal 6 is laminated and formed by the transfer, and originally, the base sheet of the transfer sheet used for the transfer and the hologram seal 6 Is bonded with a necessary adhesive force, and the base sheet and the hologram seal 6 are stably peeled off at the time of transfer. (FIG. 6
See (a). However, the release layer 62 may remain attached to the base sheet of the transfer sheet during transfer.

The material forming the release layer 62 is a mixture of an acrylic skeleton resin, a vinyl chloride / vinyl acetate copolymer, or a vinyl acetate resin and a thermosetting acrylic resin, a melamine resin, a nitrocellulose resin, or a polyethylene wax. It is particularly preferable to use an acrylic skeleton resin as a main component. Also, the release layer 62
A polyester resin may be further added in order to increase the adhesion between the substrate and the base sheet, and a wax or silicone resin may be added in order to improve releasability. The release layer 62 is formed by dissolving or dispersing the above resin in an appropriate solvent to form a release layer-forming coating composition or ink composition, using a gravure printing method, a screen printing method, or a roll coating method, for example,
The printing can be performed by printing or coating on a plastic film constituting the base material sheet by a printing means such as reverse coating using a gravure roll or a coating means, followed by drying. The release layer 62 has a thickness after drying of about 0.1 to 10 μm.

Between the release layer 62 and the hologram layer 65 and the transparent light-reflective layer 66, a release primer layer 63,
And a protective layer 64 may be interposed. These release layer 62, release primer layer 63, and protective layer 64
In addition to performing their respective nominal functions, they may be infrared absorbing, in which case there is no need to separately form an infrared absorbing layer below.

The release primer layer 63 is for ensuring the adhesive force between the release layer and the lower layer, and is auxiliary and may be omitted. The protective layer 64 is for improving the durability of the hologram, for example, abrasion resistance, solvent resistance, or contamination resistance. When the durability is required to be high, a thermosetting resin or ionizing radiation curable resin is used. It is provided by coating or the like using a conductive resin, and is cured by heating or irradiation with ionizing radiation.

The hologram layer 65 is formed by forming hologram irregularities on a synthetic resin layer. Planar holograms and volume holograms can be used as typical holograms of the optical diffraction structure. Specific examples include relief holograms, Lippmann holograms, Fresnel holograms, Fraunhofer holograms, lensless Fourier transform holograms, laser reproduction holograms (images) Hologram), white light reproduction hologram (rainbow hologram, etc.), color hologram, computer hologram, hologram display, multiplex hologram, holographic stereogram, holographic diffraction grating and the like.

As the synthetic resin constituting the hologram layer 65, polyvinyl chloride, acrylic resin (eg, PMM)
A), thermoplastic resins such as polystyrene and polycarbonate, unsaturated polyester, melamine, epoxy, polyester (meth) acrylate, urethane (meth) acrylate, epoxy (meth) acrylate, polyether (meth) acrylate, polyol (meth) acrylate , A thermosetting resin such as melamine (meth) acrylate or triazine acrylate can be used alone, or a mixture of the above-mentioned thermoplastic resin and thermosetting resin can be used. Or a material obtained by adding a radical polymerizable unsaturated monomer to these materials to make them ionizing radiation-curable. In addition, photosensitive materials such as silver salts, dichromated gelatin, thermoplastics, diazo photosensitive materials, photoresists, ferroelectrics, photochromic materials, thermochromic materials, and chalcogen glass can be used.

The formation of the hologram on the resin layer is performed as follows.
It can be formed by a conventionally known method using the above materials. For example, when recording an interference fringe of a diffraction grating or a hologram as a relief of surface irregularities, an original having the diffraction grating or the interference fringes recorded in the form of irregularities is used as a press mold, and the original is superimposed on the resin layer. By appropriate means such as a heating roll, by heat-pressing both,
The concave and convex pattern of the original can be duplicated. When a photopolymer is used, a photopolymer can be coated on the protective layer of the laminated sheet in the same manner, and then the original can be overlapped and irradiated with a laser beam to perform replication.

As described above, when the interference fringes of the diffraction grating and the hologram are recorded on the surface of the light diffraction structure layer as the relief of the surface unevenness, it is possible to copy using the obtained unevenness of the light diffraction structure. Such duplication is particularly preferable because it has mass productivity and can reduce the cost. The thickness of the hologram layer is preferably in the range of 0.1 to 6 μm,
Is more preferable.

When a diffraction grating or a hologram interference fringe is recorded as a relief of irregularities on the surface of the hologram layer 65 as described above, the light reflective layer 66 is formed on the relief surface in order to increase the diffraction efficiency. Is preferred.

As the transparent light-reflective layer 66, there is an opaque layer made of a metal thin film of aluminum or the like, or a transparent layer. In the present invention, in order to secure the visibility of the lower layer, a transparent layer is used. And it is desirable to use a transparent thin film.

As the specific transparent light-reflective layer 66, a continuous thin film made of a substance having a different refractive index from that of the hologram layer 65 is used. The thickness of the continuous thin film may be a transparent region of a material forming the thin film, but is usually 100 to 100.
0 ° is preferred. Examples of a method for forming a continuous thin film on the relief surface include a thin film forming method such as a vacuum deposition method, a sputtering method, and an ion plating method. The continuous thin film may have a refractive index larger or smaller than that of the light diffraction structure layer 64, but preferably has a refractive index difference of 0.3 or more, and a difference of 0.5 or more, and more preferably 1.0 or more. More preferably, there is.

The light has a higher refractive index than the hologram layer 65.
As a continuous thin film, ZnS, TiO _Two, Al_Two O_Three , S
b_Two S_Three , SiO, TiO, SiO_Two, Cr_Two O_ThreeSuch as
Metal oxide or metal sulfide is used. Also, holo
As a continuous thin film having a smaller refractive index of light than the Gram layer 65
Are LiF, MgF_Two , AlF_Three And the like. This
The thickness of these thin films is preferably 5 to 50 nm, more preferably.
Preferably it is 10 to 40 nm.

When the metal thin film has a thickness of 200 ° or less, the light transmittance is relatively small, so that it can be used as a light-reflective layer while being transparent. C
r, Fe, Co, Ni, Cu, Ag, Au, Ge, A
1, Mg, Sb, Pb, Cd, Bi, Sn, Se, I
A metal such as n, Ga, or Rb, an oxide thereof, or a nitride thereof is formed alone or in combination. Among them, a thin film made of Al, Cr, Ni, Ag, Au, or the like is formed. Particularly preferred.

The hologram layer 65 is made of a transparent synthetic resin having a different refractive index of light, for example, a layer of polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinyl acetate, polyethylene, polypropylene, or polymethyl methacrylate. It can also be used as the reflective layer 66.

The infrared-absorbing layer 67 is formed by dissolving an infrared-absorbing substance such as an infrared-absorbing dye or pigment or a transition metal compound or a transition metal complex in an appropriate synthetic resin binder. Alternatively, it is composed of dispersed components.

For example, among the dyes of polymethine type (eg, cyanine dye), phthalocyanine type, naphthalocyanine type, naphthoquinone type, anthraquinone type, dithiol type, or triphenylmethane type, aminium type, diimmonium type, etc. Things can be used.

Specifically, examples of the phthalocyanine-based or naphthalocyanine-based one include TX-304A and TX-305A manufactured by Nippon Shokubai Co., Ltd. Further, 1,4-di-isopentoxy-2,3-dicyanophenothiazine or 1,4-di-isopentoxy-2,3-dicyano-10 disclosed in JP-A-8-60008.
-Phthalocyanine compound obtained as a reaction product of ethylphenothiazine and a metal derivative, JP-A-9-176
No. 501, C.I. I. Pigment Green (phthalocyanine green) or the like, and a product obtained as a reaction product of an ethanethiol derivative such as 2- (n-octylamino) ethanethiol or 2-aminoethanethiol, or disclosed in JP-A-9-263717. Naphthalocyanine compounds.

As a squarylium-based compound, there is NK-2772 manufactured by Japan Photographic Dye Laboratories.

As an aminium-based compound, JP-A-7-7
No. 0496, N, N, N ', N'-tetrakis (p-dialkylaminophenyl) -p-phenylenediaminium salts.

Among the dyes available are Kayasoap CY-9 and IR-820 manufactured by Nippon Kayaku, F2GS manufactured by Bayer, and Braun GGL St manufactured by Hoechst.
ab, Braun RG Stab, ROT GGF
Stab, Blau FGStab, Blau R S
tab, Bluu 3R Stab, Grun BSt
ab, Olive HG Stab, Grau BSS
tab or Schwarz CL Stab, Sumitomo Chemical Green G, OPTOGEN NIR-
760S, OPTOGEN NIR-810, OPTO
GEN NIR-830, OPTOGEN NIR-8
40S, OPTOGEN NIR-980, OPTOG
EN DIR-100 and the like.

Thiourea structure (—NH— (C ＝ S) —N
There are the following bisthiourea compounds having two H-) in the molecule. R-NH- (C = S) -NH-Ph (Xn) -NH described in JP-A-8-109365
-(C = S) -NH-R. Wherein R is an alkyl group having 1 to 18 carbon atoms, a cyclohexyl group, an allyl group, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted alkoxycarbonyl group having 2 to 20 carbon atoms, X is a substituted or unsubstituted pyridyl group having 5 to 20 carbon atoms, wherein X is a lower alkyl group having 1 to 4 carbon atoms,
To 4 lower alkoxy groups, nitro groups, halogen atoms, or hydrogen atoms.

As disclosed in Japanese Patent Application Laid-Open No. 8-127776,
R-NH- (C = S) -NH-A-NH- (C = S)-
NH-R structure, wherein A is a divalent group having three substituted or unsubstituted benzene rings. Where R
Is an alkyl group having 1 to 18 carbon atoms, a cyclohexyl group, an allyl group, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted aralkyl group having 6 to 30 carbon atoms, Acyl group, substituted or unsubstituted alkoxycarbonyl group having 2 to 20 carbon atoms, 2 carbon atoms
To 20 monosubstituted amino groups.

As disclosed in Japanese Patent Application Laid-Open No. 8-127774,
Ra-NH- (C = S) -NH-A-NH- (C = S)
-NH-Ra. Here, Ra has 1 carbon atom.
To 18 alkyl groups, cyclohexyl groups, allyl groups, substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted aralkyl groups having 6 to 30 carbon atoms, substituted or unsubstituted 2 to 20 carbon atoms An alkoxycarbonyl group, a monosubstituted amino group having 2 to 20 carbon atoms,
A is biphenyl, and each benzene ring may be substituted with a lower alkyl group having 1 to 4 carbon atoms, a lower alkoxy group having 1 to 4 carbon atoms, a halogen atom, a sulfonic acid group, or a hydroxyl group. .

Alternatively, a compound of a transition metal such as iron, copper, chromium, cobalt or nickel, or a complex of such a transition metal can be used.

As the transition metal compound, JP-A-2000-2000
Metal oxides described in JP -1059, specifically, titanium black, black iron oxide (Fe ₃ O _4), the composite oxide _{(CuO-Cr 2 O 3,} CuO-Fe 2 O 3 -Mn 2 O ₃ , C
_{uO-Fe 2 O 3 -Cr 2} O 3) , and the like. These metal oxide pigments may be used as a mixture of two or more kinds.
Further, as the metal oxide pigment of the near-infrared absorbing material, metal composite oxides such as ilmenite, which is a composite oxide of iron and titanium, and a composite oxide of iron and copper, can be used.

The compounds of transition metals include those described in
A phosphate ester disclosed in US Pat.
Or a phosphonate and a divalent copper ion, or
Combination with tin oxide and / or indium oxide
There is something consisting of. Phosphate ester is PO (OH)
_n(OR¹)_3-nWhere R is¹Is carbon
An alkyl group of 1 to 20 or CH_Two= CXCOO
(C_TwoH_FourO) _m-Where X is a hydrogen atom or
A subscript m is an integer of 0 to 5, and n is 1
Or 2. In addition, the phosphonate ester is PO
R^Two(OH) (OR^Three), R^TwoAnd R^Three
Is an alkyl group having 1 to 20 carbon atoms,
No matter, they can be the same or different.

As the transition metal compound, JP-A-8-7
There is also a combination of cupric sulfide and a thiourea derivative disclosed in 3653.

Examples of the metal complex-based compound include SIR-159 manufactured by Mitsui Toatsu Dye Co., Ltd., a thiol Ni complex described in JP-B-60-21294, or miroly blue (iron ferricyanide complex).

JP-A-7-70363, JP-A-7-70
No. 445, JP-A-7-70481, JP-A-7-704
No. 82 or tin-doped indium oxide powder disclosed in JP-A-9-324144 can also be used. In particular,
Heat treatment in an inert gas at a temperature of about 400 ° C. to 800 ° C. so that the cutoff wavelength becomes 1000 nm or less is preferable. In addition, carbon black can be used.

In addition to these, azurenium-based, triphenylamine-based, trisazo-based, diphenylmethane-based, quinone-based, azo-based, immonium-based, or diimmonium-based materials can be used. One or two or more of them can be used by blending in the infrared absorbing layer.

Examples of the synthetic resin binder for dissolving and dispersing the above-mentioned infrared absorbing material include nitrocellulose, cellulose acetate, cellulose butyrate acetate, ethyl cellulose, polyamide resin, chlorinated rubber, cyclized rubber, polyamide resin, polyvinyl chloride. Examples thereof include resin, vinyl chloride / vinyl acetate copolymer resin, ethylene / vinyl acetate copolymer resin, chlorinated polypropylene, acrylic resin, polyurethane resin, and styrene / male resin.

Using one or more of the above-mentioned infrared absorbers, and dissolving or dispersing them using the above-mentioned synthetic resin binder, solvent and the like to obtain a composition for forming an infrared-absorbing layer, the resulting composition The infrared absorbing layer can be formed by printing or applying the product by a printing means such as a gravure printing method or a roll coating method or a coating means and then drying. Infrared absorbing layer 67
The infrared absorbing agent in the solid content of the infrared absorbing layer is 0.1%.
If the amount is less than the lower limit, infrared absorption is not sufficient, and recording cannot be performed by irradiation with laser light. If the amount exceeds the upper limit, the infrared absorbing layer is colored, In addition to impairing the visibility of the lower layer of the absorbent layer 67, the viscosity of the paint increases, and the suitability for coating deteriorates. The infrared absorbing layer 67 has a thickness of 0.1 after drying.
About 3 μm is preferable.

The adhesive layer 68 is made of a vinyl chloride resin, a vinyl acetate resin, a vinyl chloride-vinyl acetate copolymer resin, an acrylic resin, a polyester resin, a polyurethane resin, a polyamide resin, or the like. It is composed of a material appropriately selected from rubber modified products and the like. These can be used alone or as a mixed system of two or more types. Further, a hard resin, a plasticizer, and other additives can be added as necessary, and a material having high transparency can be selected. Is preferred. Although it is more convenient to provide the adhesive layer 68 on the transfer sheet, the adhesive layer 68 can be omitted from the structure of the transfer sheet if it is used by being applied to the adherend and / or the transfer sheet during transfer.

The adhesive layer 68 is formed by applying and drying a coating composition obtained by dissolving or dispersing the above-mentioned resin by an application means such as roll coating. It is preferably from 5 to 6 μm, more preferably from 1.5 to 3 μm. The adhesive layer 6
For the purpose of improving the adhesive strength between 8 and the upper layer of the adhesive layer 68 shown in each figure, an anchor layer may be formed using a known material by a known coating method or the like.

Each layer of the hologram seal 6 is sequentially formed on a base sheet made of a plastic film having mechanical strength such as a biaxially stretched polyethylene terephthalate resin film by a known coating method or the like. Go. The thickness of the plastic film is preferably about 5 to 250 μm, but the transfer or sticking is performed using a machine, and may be accompanied by heating at the time of sticking or transferring, and having an excessive thickness. Since the heating efficiency may be reduced, the thickness is more preferably about 10 to 50 μm. FIG. 6A shows a hologram seal 6 formed in the form of a transfer sheet, in which a release layer 62 is provided on the lower surface of a base sheet 61, a release primer layer 63 and a protective layer 64 provided as necessary, and a hologram layer 6.
5, which is obtained by sequentially laminating a transparent light-reflective layer 66, an infrared absorbing layer 67, and an adhesive layer 68.

FIG. 6B shows a hologram seal 6 in the form of a label. The hologram layer 65 and the hologram layer 65 are formed on the base sheet 61 via a primer layer 69 if necessary, without forming the release layer 62 or the like. The transparent light-reflective layer 66 and the infrared-absorbing layer 66 are firmly adhered to each other.
8 were obtained by laminating them. FIG. 6A and FIG.
In (b), in each case, a laminated body A in which a hologram layer 65 and a transparent light-reflective layer 66 are laminated in this order from the observation side.
Shows a light diffraction structure, but a laminated body B in which a transparent reflective layer 67 and a hologram layer 66 are laminated in this order from the observation side can also be used.
The position where 6 is stacked can be changed as appropriate, as described with reference to FIGS. 3 (a) to 3 (d).

When the surface of the hologram seal 6 is required to have durability after being attached to an adherend or after transfer, a hologram seal 6 with a protective layer 64 may be used. Further, in the label type hologram seal 6 as shown in FIG. 6B, the base sheet 61 may be laminated below the light diffraction structure layer.

By the way, when obtaining an information recording card as exemplified in FIGS. 5A and 5B, the recording on the infrared-absorbing layer is performed only after the infrared-absorbing layer is formed. , Can be performed before application to the adherend, but is typically performed in a state where the hologram seal is completed,
Then, it is good to apply to a to-be-adhered body by transfer or sticking. Alternatively, the recording may be performed on the infrared absorbing layer in the hologram seal laminated on the adherend after the hologram seal is first transferred or applied on the adherend.

As is clear from the above and the description, the hologram seal used in the present invention maintains transparency even after the recording is formed on the infrared absorbing layer, so that the hologram seal is adhered to the adherend. Even so, the visibility of the lower layer of the hologram seal at the affixed position is not hindered, so the restrictions on the position where the hologram seal is applied are eliminated, and another visual information is formed in the lower layer, and the visual information of the lower layer is Since the matched recording can be formed on the hologram seal, there is an advantage that the restriction on the design can be eliminated.

In the above description, a card, especially a credit card has been described in mind, but various ID cards such as a bank card, an identification card, a driver's license, a passport, or a membership card, a gift certificate, a gift certificate, Alternatively, the present invention can be applied to a certificate, an examination ticket, a passport, a certificate of various qualifications issued by a public organization, and the like. In addition, other than information recording media, jewelry such as precious metals and jewelry, watches (especially watches), cosmetics, household appliances, clothing, bags such as leather and cloth bags, etc., are particularly subject to fake issues. Cheap,
For the purpose of proving that the product is genuine, it can be directly pasted or transferred to a famous brand product or the like or a box or packaging bag containing the product for the purpose of proving that the product is genuine.

[0080]

EXAMPLE A hologram transfer sheet was first prepared. A 25 μm-thick polyethylene terephthalate resin film was prepared as a substrate sheet, and the following coating composition for forming a releasable layer was applied by a gravure roll coating method and dried to form a 1.5 μm-thick releasable layer. (Coating composition for forming peelable layer) ・ Acrylic resin 40 parts by mass ・ Polyester resin 2 parts by mass ・ Methyl ethyl ketone 50 parts by mass ・ Toluene 50 parts by mass

Next, the following coating composition for forming a hologram-forming layer is applied on the release layer and dried to form a resin layer for forming a hologram having a thickness of 2 μm. The hologram-forming resin layer was embossed using the original plate formed as above to transfer the hologram irregularities. (Coating composition for forming hologram layer) ・ Acrylic resin 40 parts by mass ・ Melamine resin 10 parts by mass ・ Cyclohexanone 50 parts by mass ・ Methyl ethyl ketone 50 parts by mass

After the formation of the unevenness, a TiO ₂ film having a thickness of 30 nm was formed as a transparent evaporation layer on the side having the unevenness by a vacuum evaporation method. Using the following coating composition for forming an infrared-absorbing anchor layer and the coating composition for forming an adhesive layer, an infrared-absorbing anchor layer having a thickness of 0.5 μm and a thickness of 2 μm
m of adhesive layers were sequentially laminated. (Coating composition for forming an infrared-absorbing anchor layer) 100 parts by mass of acrylic resin 0.5 parts by mass of infrared absorber (phthalocyanine compound, YKR-3080, manufactured by Yamamoto Kasei Co., Ltd.) 50 parts by mass of methyl ethyl ketone Toluene 50 parts by mass (Coating composition for forming adhesive layer) 40 parts by mass of vinyl chloride / vinyl acetate copolymer 50 parts by mass of methyl ethyl ketone 50 parts by mass of toluene

The transfer sheet composed of the base sheet / peelable layer / hologram layer / transparent reflective layer / infrared absorbing anchor layer / adhesive layer obtained above was irradiated with YAG laser light at a wavelength of 1064 nm. By adjusting the position of the objective lens, a laser beam having an output of 5 W and a beam spot size of 50 μm is focused on the above-mentioned infrared-absorbing anchor layer. , Character and image records were formed.

Separately, all are made of polyvinyl chloride resin,
Using a sublimation transfer printer, a character and a card are formed on the surface of a card base made of a four-layer laminate composed of two white core sheets and one transparent oversheet disposed on each of the front and back sides. After outputting the photograph of the face of the owner, the transfer sheets are overlaid so that the adhesive layer side faces the card base, and the release layer / hologram layer / transparent reflective layer / infrared absorbing anchor on the transfer sheet Layer / adhesive layer, characters on the infrared-absorbing anchor layer,
When the hologram sticker on which the image was recorded was transferred onto the face photo on the card substrate, characters and images were also recorded on the hologram seal without hindering the visibility of the face photo, and were superimposed on the lower layer. A card with an improved design feeling and difficulty in manufacturing was obtained.

In the above description, the laser light is
Peak power 10KW, time width 0.2μsec, beam diameter 10
Similar results were obtained using pulsed laser light narrowed down to 0 μm.

[0086]

According to the first aspect of the present invention, it is possible to provide an information recording medium having a light diffractive structure in which the lower layer can be seen while the visible recording is formed. According to the invention of claim 2, in addition to the effect of the invention of claim 1, another record recorded between the substrate and the optical diffraction structure can be seen through, so that there is no restriction due to the position of the other record. It is possible to provide an information recording medium having the applied light diffraction structure or having the light diffraction structure matched with another recording. According to the third aspect of the present invention, in addition to the effects of the first or second aspect of the present invention, since the base material has a card size, it is possible to provide an information recording medium having the convenience of a card. According to the invention of claim 4, it is possible to provide a sheet for attaching an optical diffraction structure suitable for obtaining the information recording body as described in claim 1. According to the invention of claim 5, it is possible to provide a light diffraction structure transfer sheet suitable for obtaining the information recording medium as described in claim 1. According to the invention of claim 6, the sheet for attaching the light diffraction structure according to claim 4 is prepared by previously laminating the base material of the information recording body,
The information recording medium as described in claim 1 can be completed by irradiating a laser beam, and a manufacturing method suitable for issuing the information recording medium can be provided each time. Claim 7
According to the invention of the present invention, since a record composed of areas having different degrees of discoloration is previously formed in the infrared absorbing layer of the sheet for attaching a light diffraction structure according to claim 4, compared to the information recording body of a finished product, Since the recording is collectively formed on the light-diffraction structure attaching sheet having a small thickness and then laminated, the efficient manufacturing method can be provided when the recording is formed in a large amount on the light diffraction structure. According to the eighth aspect of the present invention, it is possible to provide a method of manufacturing an information recording medium that can obtain the same effect as that of the sixth aspect of the invention, except that it is previously transferred to the base material of the information recording medium.
According to the ninth aspect of the present invention, it is possible to provide a method of manufacturing an information recording medium that has the same effect as that of the seventh aspect of the invention except that the application to the information recording medium is performed by transfer.

[Brief description of the drawings]

FIG. 1 is a plan view when applied to a card.

FIG. 2 is a longitudinal sectional view of the card.

FIG. 3 is a sectional view of a hologram seal.

FIG. 4 is a plan view of an application example of the hologram seal.

FIG. 5 is a sectional view showing a specific state applied to a card.

FIG. 6 is a cross-sectional view showing a specific example of a hologram seal.

[Explanation of symbols]

 Reference Signs List 1 card 2 base material 4 embossed character 6 hologram seal 7 hologram 8 image 9 unique information for each base material 10 unique information for each light diffraction structure 61 base material sheet 62 peelable layer 63 release primer layer 64 protective layer 65 hologram layer 66 Transparent light reflective layer 67 Infrared absorbing layer (67a; record) 68 Adhesive layer

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) G09F 1/02 G09F 19/12 L G06K 19/00 D 19/12 F (72) Inventor Yasuhiro Oba Ichigaya, Shinjuku-ku, Tokyo 1-1-1 Kagacho F-term in Dai Nippon Printing Co., Ltd. (reference) 2C005 HA02 HB02 HB04 HB09 HB10 JA18 JB08 JB09 JB12 KA40 LA19 LB16 LB17 5B035 AA15 BA05 BB05 BC00

Claims (9)

[Claims] 1. A light diffraction structure comprising at least a transparent light-reflective layer and a light diffraction structure layer is embedded in a base material so as to be observable from above the base material, or is laminated on the base material. Laminated, between the substrate and the light diffraction structure, or on the light diffraction structure, an infrared-absorbing layer is laminated, and the infrared-absorbing layer, from the area of different degrees of discoloration An information recording medium, characterized in that a recording is formed. 2. Between the substrate and the light diffraction structure,
2. The information recording medium according to claim 1, wherein further information is recorded. 3. The information recording medium according to claim 1, wherein the base material has a portable card size. 4. A light diffraction structure comprising at least a transparent light-reflective layer and a light diffraction structure layer is laminated on a transparent substrate sheet, and between the transparent substrate sheet and the light diffraction structure, or On the light diffraction structure, an infrared absorbing layer is laminated, and the side opposite to the side having the light diffraction structure of the transparent substrate sheet, or the side opposite to the transparent substrate sheet of the light diffraction structure. A light-diffraction structure adhering sheet, further comprising an adhesive layer laminated thereon. 5. A light diffractive structure comprising at least a transparent light-reflective layer and a light diffractive structure layer is laminated on a releasable surface of a releasable substrate sheet, and the releasable substrate of the light diffractive structure is provided. A light diffraction structure transfer sheet, wherein an infrared absorbing layer is laminated on the sheet side or on the light diffraction structure, and an adhesive layer is further laminated on the uppermost layer. 6. A sheet for laminating an optical diffraction structure according to claim 4 is laminated on a substrate with its adhesive layer side facing the substrate, and then the infrared absorbing layer is irradiated with laser light. Forming a record comprising areas having different degrees of discoloration in the infrared absorbing layer. 7. Irradiating a laser beam to the infrared absorbing layer of the sheet for attaching a light diffraction structure according to claim 4,
A record comprising areas having different degrees of discoloration is formed on the infrared-absorbing layer, and then the light-diffraction structure-attached sheet on which the record has been formed is laminated with the adhesive layer side facing the substrate. Manufacturing method of an information recording medium. 8. The transfer layer is transferred onto a substrate using the light diffraction structure transfer sheet according to claim 5, and thereafter, the infrared ray absorbing layer in the transferred transfer layer is irradiated with laser light. The method for producing an information recording medium, wherein a record comprising areas having different degrees of discoloration is formed in the infrared absorbing layer. 9. A recording comprising areas having different degrees of discoloration on the infrared absorbing layer by irradiating the infrared absorbing layer in the transfer layer of the light diffraction structure transfer sheet according to claim 5 with laser light. Then, using the optically diffractive structure transfer sheet on which the recording has been formed, the adhesive layer side is transferred to the base material to transfer the information.