JP2012208365A - Hologram label - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a novel hologram label using a hologram in which, in order to enhance authenticity, hologram reproduction of a wavelength different from illumination light is performed, which is different from a hologram reproducing a hologram reproduction image of a wavelength equal to illumination light.SOLUTION: A photochromic thin film layer is provided on a hologram formation layer. The photochromic thin film layer is illuminated with excitation light. A hologram reproduction image by color tone of light emission thereof in a visible light region is made detectable by visual inspection. Accordingly, forgery prevention property is enhanced.

Description

The present invention relates to a novel hologram label, in particular, a coloring type or “discoloration” type hologram label in which a photochromic thin film is arranged at the relief position of a relief hologram that exhibits a phase hologram.
Hereinafter, the change of the photochromic thin film layer from a “colorless” or “white” state to a “colored” state is referred to as “coloring” by a predetermined excitation light (ultraviolet light, etc.). The change to “color tone” is referred to as “discoloration” by predetermined excitation light (ultraviolet rays or the like).
In the present specification, “part” indicating the formulation is based on mass. The “hologram” includes a hologram and a hologram having a light diffractive function such as a diffraction grating. “Diffraction gratings” include those formed optically such as optical interference fringes and those formed by a direct drawing method such as an electron beam drawing method.
In the present invention, “inactivation treatment” means “another resin layer” that is laminated on the surface of the resin layer, for example, by reducing the surface tension of the surface of the resin layer. Adhesive strength is reduced, and the adhesion strength at the interface between the two layers in the lamination of “one resin layer” and “another resin layer” (meaning “peel strength” by the 180 ° peel test specified in JIS Z0237) (Hereinafter, also referred to as peel strength)), the “adhesion strength” of the region that has been “inactivated” is the original “adhesion strength” of the region that has not been “inactivated”. It means that a process of lowering is performed.
By this treatment, a region having a large surface tension and a region having a small surface tension appear on the outermost surface of the “certain resin layer”.
This “inactivation treatment” includes “activation treatment” of the entire surface of “a certain resin layer”, followed by inactivation treatment of a part thereof. As a result, both “laminated” layers Forming a portion having a lower adhesive strength than other regions in a partial region of the interface.
Of course, even when the adhesive strength between “a certain resin layer” and “another resin layer” is small (that is, the surface tension of “another resin layer” is small), By “inactivating” a part of the outermost surface, this results in the formation of a part having a lower adhesive strength than the other part in a part of the interface between the “laminated” layers. .

(Main applications)
The main use of the hologram label of the present invention is a hologram label used in the field of forgery prevention. Specifically, when it is used by forgery of a credit card or the like, it is used for a card holder or a card company. Damaged items, driver's license, ID card, employee ID card, membership card, entrance examination card, passport, banknote, gift certificate, point card, stock certificate, securities, lottery ticket, horse pass, bankbook , Boarding tickets, toll tickets, air tickets, admission tickets for various events, play tickets, prepaid cards for transportation and public telephones.
Each of these is an information recording body that holds information having economic or social value, and it is desirable to have a function that can identify the authenticity of the recording body for the purpose of preventing damage caused by forgery. .

In addition to these information recording media, expensive products such as luxury watches, luxury leather products, precious metal products, jewelry, etc., often referred to as luxury brand products, or storage of such expensive products. Boxes and cases can also be forged. In addition, mass-produced products of famous brands, such as audio products, electrical appliances, etc., or tags that are hung on them are also subject to forgery.
Furthermore, a storage body in which music software, video software, computer software, game software, or the like, which is a copyrighted work, or cases thereof can also be forged. In addition, it is desirable that products such as printer toner, paper, and the like in which supplies to be replaced are limited to genuine materials have a function of identifying their authenticity for the purpose of preventing damage caused by forgery.

(Background technology)
Conventionally, for the purpose of preventing counterfeiting of information recording bodies and various articles described above (collectively referred to as authenticity identification objects), it is said that they have manufacturing difficulties due to the precision of their structures. In many cases, holograms are applied as authenticity distinguishable. However, since the hologram manufacturing method itself is known and can be precisely processed by that method, when the hologram is merely for visual judgment, there is no difference between a genuine hologram and a forged hologram. It is difficult to distinguish.
These authentic identification objects, in particular, articles that have been subjected to hologram images in a label form or transfer form, are not only used for authentic identification of visual confirmation of hologram images, but also by using a new authenticity identification method. There is a need to identify the authenticity of.

(Prior art)
In order to meet these requirements, a hologram label having a light selective reflection layer that is laminated on a hologram and reflects only one of the left-handed polarized light and the right-handed polarized light in the incident light has been proposed. (For example, refer to Patent Document 1.)
As this light selective reflection layer, cholesteric liquid crystal is used, and the anti-counterfeiting property is enhanced by a method of confirming using a polarizing plate or the like.
However, as described in Patent Document 1, since the reflectance of the reflective thin film layer on the hologram forming layer is high, the light that is transmitted without being reflected by the cholesteric liquid crystal layer (complementary light of selective reflected light) Reflecting on the reflective thin film layer and returning to the cholesteric liquid crystal layer again (hereinafter referred to as return light), this return light becomes a noise component when observing the cholesteric liquid crystal and is added to and mixed with the selectively reflected light. However, the color tone was not the original color of the liquid crystal, and it was even difficult to see and identify.

In addition, the cholesteric liquid crystal material itself is expensive, and in order to draw out the liquid crystal performance, it is indispensable to form an alignment film in contact with the liquid crystal layer. There have been problems such as blurring and distortion of the image when light for reproducing the image passes through the liquid crystal layer.
For this reason, it has been devised to suppress the light scattering property of the cholesteric liquid crystal layer or to make the cholesteric liquid crystal layer itself thin. However, in order to suppress the light scattering property of the cholesteric liquid crystal layer, the refractive index difference is reduced, When the liquid crystal layer is made thin, the function as the light selective reflection layer described above is deteriorated, and it has a drawback that it is difficult to obtain optimum conditions for ensuring the clarity and anti-counterfeit performance of the hologram image. .
Furthermore, a forgery prevention method is proposed in which the hologram forming layer is made of a photochromic material, and a hologram relief and a reflective thin film layer are formed on one surface of the photochromic layer, thereby concealing the presence of the hologram relief. However, the photochromic layer in this stack only serves as a layer that “changes the unexpected color tone”, and is insufficient as an anti-counterfeit effect. (For example, see Patent Document 2.)

JP 2007-90538 A JP-A-3-248188

  Accordingly, the present invention has been made to solve such problems. The purpose is to provide a phase hologram hologram forming layer, that is, a photochromic thin film layer so as to be in contact with the hologram relief, or to form a part of the photochromic thin film layer in synchronization with the hologram relief, and only under predetermined conditions. It is an object of the present invention to provide a novel hologram label capable of visually recognizing a hologram having a different color tone or visually recognizing a hologram having a changed color tone under a predetermined condition. Furthermore, when this hologram label is illegally peeled off, the photochromic thin film layer is deformed, and it is highly counterfeiting that the hologram to be reproduced is smeared without being noticed by the person who performed the fraud. It is to provide a hologram label having.

To solve the above problem,
The first aspect of the hologram label of the present invention is:
A transparent resin layer having a hologram relief including a diffraction grating group corresponding to a hologram image on one surface of the transparent substrate, and a photochromic provided following the unevenness forming the hologram relief and having a uniform thickness A hologram label provided with a thin film layer and an adhesive layer, wherein a part of the hologram relief surface of the transparent resin layer is inactivated.
According to the hologram label of the first aspect,
A transparent resin layer having a hologram relief including a diffraction grating group corresponding to a hologram image on one surface of the transparent substrate, and a photochromic provided following the unevenness forming the hologram relief and having a uniform thickness A hologram label provided with a thin film layer and an adhesive layer, wherein a part of the hologram relief surface of the transparent resin layer is inactivated. Thus, it is possible to provide a hologram label having a high anti-counterfeit property capable of leaving a trace of the fraud without being noticed by a person who has illegally peeled off the hologram label.
The second aspect of the hologram label of the present invention is:
The photochromic thin film layer is formed only in concave and convex recesses forming the hologram relief.
According to the hologram label of the second aspect,
The hologram label according to the first aspect in which the photochromic thin film layer is formed only in the concave and convex concave portions forming the hologram relief can be provided. In addition to the features of the first aspect, the photochromic thin film layer can emit light. In this case, a hologram label can be provided in which a clearer hologram reproduction image can be visually recognized.
Furthermore, the third aspect of the hologram label of the present invention includes:
The photochromic thin film layer has a thickness of 0.01 μm or more and 0.5 μm or less.

According to the hologram label of the third aspect,
The hologram label according to the first aspect or the second aspect, in which the photochromic thin film layer has a thickness of 0.01 μm or more and 0.5 μm or less, in addition to the characteristics of the first or second aspect, When the photochromic thin film layer is caused to emit light, it is possible to provide a hologram label in which a remarkably clear hologram reproduction image can be visually recognized.
And the hologram label which is the 4th aspect of the present invention is:
The partial area of the hologram relief surface of the hologram label according to any one of the first to third aspects that is subjected to the inactivation process is a collection of fine pattern shapes having a size of 50 μm to 300 μm. It is characterized by this.
According to the hologram label of the above aspect,
The partial area of the hologram relief surface of the hologram label according to any one of the first to third aspects that is subjected to the inactivation process is a collection of fine pattern shapes having a size of 50 μm to 300 μm. The hologram label characterized by the above can be provided, and the hologram label can be provided, which can further make the hologram reproduction image unclear when the hologram label is illegally peeled off.

In the hologram label of the present invention, a diffraction grating group for reproducing a hologram image is formed as a hologram relief on a surface of a transparent resin layer formed on one surface of a transparent substrate as a substantially flat surface. Alternatively, the photochromic thin film layer is provided with a uniform thickness following the relief.

In other words, the hologram relief shows a phase difference as a phase hologram in a “relief shape (means an uneven shape)”, but follows (along) a “relief shape” having this phase difference. By providing the layer, the color tone exhibited by the photochromic thin film layer is observed with (including) the phase difference. In other words, “light” having a “color tone” that the photochromic thin film exhibits under a predetermined condition “emits” from the photochromic thin film layer.
When the photochromic thin film layer has transparency or is “white” (meaning that it is visually recognized as “white” by the light scattering property of the photochromic material surface), the photochromic thin film layer Under illumination light other than the illumination light that emits light, it is visually recognized as a simple transparent label or a white label.
Therefore, in the use of the various hologram labels described above, printed layers such as characters and designs suitable for the use are placed above and below each layer constituting the hologram label, in particular, between the transparent substrate and the transparent resin layer. It is preferable to provide it.
In addition, when the photochromic thin film layer already exhibits a “color tone” (means a state of “colored”), it can be visually recognized as a hologram label with the color tone under normal indoor illumination light. The hologram label, such as “Authenticity”, which has a certain color tone and “same color” (meaning that the three elements of color “hue”, “color” and “lightness” substantially match) ”is genuine It is preferable to provide a printing layer such as a letter or a design meaning that there is a top and bottom of each layer constituting the hologram label, in particular, between the transparent substrate and the transparent resin layer.
As a result, when the photochromic thin film layer is irradiated with predetermined excitation light and changed in color by the predetermined excitation light, characters such as “authenticity” can be lifted.
Range of "same color" in this case, "color difference", for example, L * a * b * chromaticity diagram in (LAB color system) △ E {= (△ a 2 + △ b 2 + △ L 2 ) ^1/2 )} means that ΔE is 0.5 or less.
Color systems proposed by the International Commission on Illumination (CIE) include other RGB systems, XYZ systems (Yxy systems), UVW systems (Luv systems), etc., but these are correlated and can be converted easily. And the conversion value can also be used.
The change in “color” is recognized as “difference” when ΔE exceeds 0.5 (SLIGHT: the difference is felt slightly), and clearly exceeds “1.5” when ΔE exceeds 1.5. “Difference” can be visually recognized (NOTICEABLE: the difference is felt considerably).

Such a “normal label having a normal design” or a “label” that can only be visually recognized as a hologram label exhibiting a certain color tone is “colored” or “discolored” by a predetermined excitation light, and the “colored” A hologram reproduction image having a wavelength or “discoloration” wavelength appears.
In addition, if the hologram label is illegally peeled off, deformation force or tension is applied to the hologram label as a result of the peeling force, and this force causes “inactivation treatment of a part of the hologram relief surface of the transparent resin layer. Interfacial delamination occurs preferentially in the “region”, and the photochromic thin film layer of the hologram label is partially deformed in that portion.
That is, the hologram relief shape of the photochromic thin film layer, which is the light emitting surface for reproducing the hologram reproduction image, is partially distorted, and the “phase information” held by the shape of the photochromic thin film layer is disturbed. Reduces the interference effect (means the effect that light emitted from each unevenness of the hologram relief interferes with each other and strengthens or weakens to form a hologram reproduction image) and reduces the hologram The brightness of the reproduced image and the contrast thereof are lowered and the image becomes unclear.
When the deformation reaches a relatively large area of the photochromic thin film layer (meaning most of the hologram relief forming surface), the reproduced hologram reproduced image itself is distorted (interfering with each other and strengthening each other). This means that the traveling direction of “light for forming a hologram reproduction image” is disturbed.
Furthermore, in the part where the interfacial peeling occurs, “air gap” is generated, and “air” enters this part, so that the interface between this “air” and the transparent resin layer, and “air” and the photochromic thin film layer In the photochromic thin film layer located under this “gap”, the illuminance of the predetermined excitation light is greatly reduced and the photochromic thin film layer at that position “Color development” or “discoloration” does not occur sufficiently, and “color development” lacks its brightness (lightness), or “color change” includes “original color tone” and “new color tone”. Will be mixed.

Therefore, as a result, there is a difference in “brightness” and “color tone” between the photochromic thin film layer located under this “gap” and the photochromic thin film layer located at other positions.
In order to easily determine such a phenomenon visually, “print layer A” by “color” before “discoloration” and “color” after “discoloration” in an area where “void” does not occur. And “print layer B” of “same color” are preferably provided in the hologram label.
That is, in the photochromic thin film layer that "discolors"
In the area where the "void" is not generated,
・ Before “color change”, “print layer A” is not visible, and “print layer B” is clearly visible,
・ After “discoloration”, “printing layer A” is visible and “printing layer B” is not visible.
Confirm the phenomenon, determine the “authenticity” of the hologram label,
In the area where the "void" is generated,
・ Before `` discoloration '', it is visible as above,
• After “discoloration”, “printing layer A” can be visually recognized, and “printing layer B” can also be visually recognized, and the “trace of peeling hologram label” can be easily determined.
Also, in the photochromic thin film layer that “colors”, “printing layer B” with “color” and “same color” after “coloring” is provided in the hologram label,
In the area where the "void" is not generated,
・ After “coloring”, confirm the phenomenon that “printing layer B” becomes invisible, determine the “authenticity” of the hologram label,
In the area where the "void" is generated,
・ After “coloring”, the “printing layer B” remains visible due to the difference in “brightness”, and the “trace from which the hologram label has been peeled off” can be easily determined.
Such “deformation of the photochromic thin film layer” does not show any change in the appearance of the hologram label, so those who have performed the fraudulent act are left with such “traces of fraud”. For those who have no idea of this and who confirm fraudulent behavior, it is easy to determine the presence or absence of the “trait of fraud”.

The transparent base material used in the present invention is preferably one having a thickness that can be reduced and having a mechanical strength and a solvent resistance and a heat resistance that can withstand processing when manufacturing a hologram label. Since it depends on the purpose of use, it is not limited, but a film or sheet plastic having a thickness of 5 to 250 μm is used.
As a transparent resin material constituting a transparent resin layer having a hologram relief (hereinafter also referred to as a hologram forming layer) formed on a transparent substrate, various thermoplastic resins, thermosetting resins, or An ionizing radiation curable resin can be used, and a transparent resin layer having a thickness of 5 μm to 50 μm is formed using various coating methods such as a gravure coating method, various printing methods such as an offset printing method and a screen printing method.
In order to form a transparent resin layer having a hologram relief using the above-described transparent resin material, it can be formed directly by developing the photosensitive resin material by performing interference exposure of the hologram, but prepared in advance. It is preferable to perform molding by using the relief hologram or a duplicate thereof, or a plating mold thereof as a replication mold, and pressing the mold surface against the layer of the resin material.
When thermosetting resin or ionizing radiation curable resin is used, curing is performed by heating or ionizing radiation irradiation while keeping the uncured resin in close contact with the mold surface, and then cured by peeling after curing. The fine irregularities of the relief hologram can be formed on one side of the layer made of a transparent resin material. A diffraction grating forming layer having a diffraction grating formed in a pattern by a similar method can also be used as the optical diffraction structure.
A relief hologram is a recording of interference fringes due to interference of light between object light and reference light in an uneven relief shape. For example, a laser reproduction hologram such as a Fresnel hologram, a white light reproduction hologram such as a rainbow hologram, There are color holograms utilizing these principles, computer generated holograms (CGH), holographic diffraction gratings, and the like. Further, like a machine readable hologram, the reproduction light may be converted into data by a light receiving unit and transmitted as predetermined information, or authenticity may be determined.

In order to precisely create fine irregularities, not only optical methods, but also electron beam lithography equipment can be used to create precisely designed relief structures that produce more precise and complex reproduction light. Good. The relief shape is designed to have a pitch, depth, or specific periodic shape of the unevenness according to the wavelength (range) of the light or light source for reproducing or reproducing the hologram, the direction and the intensity of reproduction or reproduction. The pitch (period) of the unevenness depends on the reproduction or reproduction angle, but is usually 0.1 μm to several μm, and the depth of the unevenness is a factor that greatly affects the reproduction or reproduction intensity, but is usually 0.1 μm. ˜1 μm.
Then, “inactivation treatment” is performed on a part of the surface of the transparent resin layer having the hologram relief. Here, “part” means a “part” area, that is, “region” with respect to the entire hologram relief surface. This “region” may be a continuous region or a collection of discrete regions.
In the inactivation treatment to this “region”, only a very small distance (for example, 0.001 μm) from the surface to the inner surface (thickness direction) of the transparent resin layer only from the outermost surface of the hologram relief surface. The property of the resin in the portion of about 0.01 μm is modified or modified. Alternatively, a method that does not cause a substantial change in the hologram relief shape of the transparent resin layer is used even when modifying or modifying a distance longer than this.
“Deactivation treatment” is a method of performing “deactivation treatment” directly on the transparent resin layer, for example, using a thermosetting resin or a resin to which a curing agent is added. First of all, "Activation treatment", such as a method of completely curing by heating to eliminate unreacted components or a method of bleeding the formed part to the outermost surface by partial heating or partial curing of the resin containing the release component "For example, carbon dioxide laser irradiation, far-infrared carbon dioxide laser irradiation, 172 nm vacuum ultraviolet (VUV, excimer light) irradiation, oxygen-sensitized excimer light irradiation, larger than the chemical bonding energy of the outermost surface of the transparent resin layer such as plasma treatment The chemical bond on the outermost surface of the transparent resin layer is broken by energy (7.2 eV), or it is absorbed by oxygen in the atmosphere and emits ozone or directly excited oxygen, such as vacuum ultraviolet rays of 172 nm. Then, using physical treatment such as generation of a functional group by this contact, only the outermost surface of the transparent resin layer is “activated (meaning that the surface tension increases)” and then activated. Solvent that dissolves only the outermost surface in a part (region) of the outermost surface of the transparent resin layer or reacts with the activated functional group on the outermost surface to eliminate the activity of the functional group Using a letterpress printing method or an inkjet method, patterning is performed avoiding contact with the activated surface, reacting only with the activated outermost surface portion of the transparent resin layer, and only that portion. There is a method to inactivate.

According to these methods, the shape of the hologram relief on the transparent resin layer does not cause “change” in a precise sense. Therefore, the shape of the photochromic thin film layer formed on the hologram relief is precisely “hologram”. Relief shape.
For example, according to the latter deactivation treatment, with polyethylene terephthalate resin, the surface tension increased to 60 mN / m becomes 36 mN / m, and the peel strength from the melamine resin as the transparent resin layer is 0.8 kg / 25 mm width. To 0.1 kg / 25 mm width, and the difference in peel strength between the “deactivation treatment” region and other regions can be increased.
In addition, as the “inactivation treatment”, a resin having a low surface tension, such as a silicone resin or a paraffin resin, which is difficult to adhere to the transparent resin layer in the first place, is formed on the transparent resin layer. There is also a method of reducing the peel strength between the photochromic thin film layer and the transparent resin layer, but in this case, this silicone resin or the like remains with a “thickness” on the hologram relief of the transparent resin layer, Since the “relief shape” of the photochromic thin film layer formed on the photochromic thin film layer is far from the original hologram relief shape, the method cannot be used. (Of course, any type can be used as long as it is of a “soaking type” in the transparent resin layer and does not substantially add any “thickness” on the hologram relief.)
This is because the depth of the concavo-convex shape of the hologram relief is about 0.1 μm, so even if there is a resin residue with a thickness of about “0.01 μm” that is 1/10 of the depth, This is because it has a great influence on the clarity.
Therefore, “deactivation treatment” with such silicone resin or the like is performed on the photochromic thin film layer in which a photochromic thin film layer is formed on the transparent resin layer and the photochromic thin film layer is made into a “precise hologram relief shape”. The method of providing the part which easily peels in the interface of a photochromic thin film layer and an adhesive bond layer by providing the silicone resin etc. in this is suitable.
Of course, it is also preferable to subject the photochromic thin film layer to an inactivation treatment similar to that of the transparent resin layer. It is also preferable to synchronize with the position of the crystallization process because the deformation effect of the photochromic thin film layer is increased (tuning is a position that overlaps completely when viewed from the observation side of the hologram label in the direction perpendicular to the hologram label. In any case, the photochromic thin film layer may be easily deformed in accordance with the thickness and material of the photochromic thin film layer.

Then, the region to be deactivated, that is, a part of the hologram relief surface subjected to the deactivation process is made a “collection of fine pattern shapes” having a size of 50 μm to 300 μm, so that photochromic Deformation of the thin film layer occurs more efficiently, and in addition to this “collection of fine pattern shapes”, “color development” and “discoloration” are insufficient, and “color development” and “discoloration” are sufficient. It is possible to make it possible to easily determine visually a trace in which an illegal peeling action has been performed.
The “fine pattern shape” is, for example, a halftone dot shape, a checkered pattern, a random pattern, etc., and only the portion of the “fine pattern” is inactivated, that is, the “fine pattern” and “ By not inactivating the area between the `` fine patterns ''
In the case of a halftone dot shape, the inside of the halftone dot is inactivated, and the area between the halftone dots is not deactivated. By separating only one part of the cut-off cell, and inactivating the other cells, the peel strength at the interface between the transparent resin layer having the hologram relief and the photochromic thin film layer is increased. By applying the strength of a fine dot pattern or a fine checkered pattern, the deformation given to the photochromic thin film layer and the size of the voids are set to 50 μm to 300 μm, which are visible sizes.
For this reason, the individual size of the “fine pattern” (if it is a checkered pattern, it means the size of one cell) is 50 μm to 300 μm. Preferably, it is 100 micrometers-300 micrometers.
If the individual size of the “fine pattern” is larger than 300 μm, the deformation period of the photochromic thin film layer with respect to the hologram relief shape is too large, and it is difficult for the deformation to reduce the interference effect of the unevenness of this part. If the thickness is less than 50 μm, the individual areas of the inactivation process become too small, and visual determination by the above-described method becomes difficult.
The range for performing the inactivation process can be applied to the entire transparent resin layer having the hologram relief. However, since the purpose of the inactivation process is “judgment of fraud”, It is also preferable to limit the application to a partial range (1/10 to 1/25) in order to further conceal the existence of such processing.

Here, the principle of appearance of the hologram reproduction image will be described below.
In the case of the hologram label of the present invention, the “light” that the photochromic thin film layer exhibits by “light emission” or “discoloration” is generated in the case of the Huygens secondary wave that is generated when the relief hologram is reproduced (the source of hologram reproduction). The equivalent of this secondary wave is the color tone (hereinafter referred to as “emitted color” or “discolored color”) of the photochromic thin film disposed on the hologram relief surface. This colored light plays a role, and includes the phase difference of the hologram relief including the diffraction grating group corresponding to the hologram image. It is something that radiates to the side.
This colored light causes an interference phenomenon in the space on the hologram relief surface, and as a result, a predetermined hologram reproduction image appears in a predetermined direction.
The manner in which the photochromic thin film changes its color tone will be described below using a photochromic molecular potential curve (see FIG. 1).
The photochromic molecule A obtains energy by irradiation with light having a certain wavelength λ and becomes a molecule A * in an excited state. (STEP1)
At this time, the excited photochromic molecule A * undergoes an intramolecular reaction, for example, cis-trans isomerization reaction, ring-closing / ring-opening reaction, oxidation / reduction reaction, tautomerization by hydrogen transfer, etc. Changes the molecular geometry and electronic structure.
By this change, the photochromic molecule A * changes to a photochromic molecule B that absorbs light λ ′ having a wavelength different from that of the photochromic molecule A.
Then, the photochromic molecule B 1 absorbs light having the absorption wavelength λ ′ (STEP 2) or absorbs thermal energy (STEP 3), and returns to the photochromic molecule A again.
Then, STEP 1 to STEP 3 can be repeated.
At this time, the ease of heat return from the photochromic molecule B 1 to the photochromic molecule A is based on the ground state potential energy ΔE (FIG. 1: STEP 3
).
If it is difficult for heat to return, that is, if ΔE is extremely large, if it is stored in a dark place, the colored body will be maintained as it is. (Such photochromic molecules are called P-type in the sense that they depend only on light.)
On the other hand, ΔE is relatively small when the light is lost and the color is quickly removed or the original color tone is restored. (Such photochromic molecules are called T-type in the sense that they are thermally dependent.)

That is, the photochromic thin film is composed of photochromic molecules A in some cases, and is composed of photochromic molecules B in some cases.
Each of the photochromic molecules A or B has a characteristic light absorption curve. The photochromic molecule A has a large absorption (curved) portion at the wavelength λ and the photochromic molecule B has a large absorption (curved) portion at the wavelength λ ′.
As an example, when the wavelength λ of the photochromic molecule A is in the ultraviolet region, the photochromic molecule A is colorless and transparent, and only after it has changed to the photochromic molecule B through the excited state A *, is in the visible light region. A specific color tone is exhibited by absorption of light centered on the wavelength (which may be the wavelength λ ′).
This "color tone" situation is that the photochromic molecule B has a predetermined light absorption curve in the visible light region, and when the photochromic molecule B is irradiated with white light, a predetermined wavelength including a specific wavelength is included. The light in the wavelength region that absorbs the light in the region and is not absorbed is emitted as divergent light from the holographic film layer made of the photochromic molecule B.
In the hologram label according to this example, the divergent light emitted from the photochromic molecule B plays the role of the Huygens secondary wave described above.
Therefore, when the photochromic thin film layer is composed of photochromic molecules A, this photochromic thin film layer is colorless and transparent, and it cannot be recognized that there is a hologram at that position, and what is behind the photochromic thin film layer is visible. However, by applying illumination light of wavelength λ to the photochromic thin film layer, the photochromic thin film layer diverges light in the above-mentioned wavelength region, and due to interference of the divergent light, a hologram based on the “color tone” of the divergent light is in the air. It will appear to float.

When the photochromic thin film layer is the above-described P-type, the hologram reproduction image by the “color tone” of the diverging light is maintained in the “color tone” for a while and is gradually decolored, and the photochromic thin film layer is In the case of the above-described T type, the “color tone” disappears relatively quickly and becomes colorless and transparent again.
In addition, when both the photochromic molecules A and B exhibit a color tone in the visible region, a phenomenon in which the color tone of the hologram reproduction image changes appears.
Such an effect of the hologram label of the present invention may be regarded as a design property and employed for appreciation.
In addition, among T-types, the decoloring speed is very fast, and the design is such that the illumination of wavelength λ is removed and the color is erased at the same time. (Kimono) Hold the hologram label (or hologram label stuck product) from the holder, quickly irradiate with illumination of wavelength λ for a short time, and at that moment, visually check the hologram reproduction image by the colored light, It is possible to confirm the authenticity and then immediately return the hologram label (or the attached hologram label) to the holder without making the holder aware of it. You can also
In this case, it is necessary to design the decoloring speed as a half-life of the color development intensity (color density) and to have a half-life of 0.1 to several seconds. In this way, when the light with the wavelength λ is irradiated, the above-described change occurs quickly, and a “color tone” hologram reproduction image of the photochromic molecule B appears. When the irradiation with the light with the wavelength λ is stopped, The hologram label which is excellent in authenticity determination can be provided.
Of course, it is also preferable to use a determination system that confirms color development after irradiating light of wavelength λ and quickly irradiates light of wavelength λ ′.

Next, the principle of holography will be described.
If the object is illuminated with coherent light and the light diffracted from the object illuminates the recording medium (photoresist, etc.), the object wave diffracted from the object and reaches the recording surface is
F (x, y) = A (x, y) EXP [φ (x, y)]
It is expressed. here,
A (x, y) is the amplitude distribution of the object wave,
φ (x, y) is a phase distribution.
At this time, the intensity distribution of the light wave reaching the recording medium is recorded on the recording medium. Its intensity distribution is
I (x, y) = | F (x, y) | ² = A ² (x, y) (1)
Thus, the phase distribution is not recorded.
Here, when an object wave and a coherent light wave (referred to as a reference wave) are superimposed, the intensity distribution of the recorded light wave is
I (x, y) = | F (x, y) + R (x, y) | ²
= | F (x, y) | ² + | R (x, y) | ²
+ F (x, y) R ^* (x, y) + F ^* (x, y) R (x, y) (2)
It becomes. (* Represents a complex conjugate term.)

However, if the reference light is a plane wave incident on the recording surface at an angle θ,
R (x, y) = r (x, y) EXP (2πiαx) (3)
Write,
α = SIN (θ) / λ (4)
It is. In the first and second terms of (2), the phase information is missing for both the intensity of the object wave and the intensity of the reference wave. The third term and the fourth term are interference terms. F (x, y) R * (x, y) =
A (x, y) r (x, y) EXP [i [φ (x, y) -2παx]] (5)
F * (x, y) R (x, y) =
A (x, y) r (x, y) EXP [-i [[phi] (x, y) -2 [pi] [alpha] x]] (6)
The phase term φ (x, y) of the object remains. (5) and (6) are complex conjugates of each other, and the third term in (4.2) includes the complex amplitude distribution of the object. Substituting (5) and (6) into (2),
I (x, y) = | F (x, y) | ² + | R (x, y) | ²
+ 2A (x, y) r (x, y) COS [2παx−φ (x, y)] (7)
It becomes. It can be seen that the object wave and the reference wave interfere to form an interference fringe.

In this way, holography is a method in which a reference wave is superimposed on an object wave and interference recording is performed, and the phase information of the object is recorded without being lost. A recording of (7) is called a “hologram”. The amplitude transmission or reflection of the hologram is proportional to the recorded intensity distribution I (x, y)
T (x, y) = τI (x, y) (8)
Let's call it. When the reference wave used when recording on this hologram is at a predetermined angle, the wavefront transmitted or reflected by the hologram is
T (x, y) R (x, y) = τ (| F (x, y) | ² + | R (x, y) | ² )
+ ΤF (x, y) | R (x, y) | ²
+ ΤF ^* (x, y) R ² (x, y) (9)
Can be expressed. This second term is τF (x, y) | R (x, y) | ² =
τA (x, y) r ² (x, y) EXP [iφ (x, y)]] (10)
The third term is
τF * (x, y) R ² (x, y) =
τA (x, y) r ² (x, y) EXP [−iφ (x, y) + 2πiα] (11)
Call it.

Therefore, the first term of (9) is a light beam penetrating the hologram in the same direction as the illumination light or a specularly reflected light beam, and the second term is a light wave having an amplitude proportional to the object light from (10). From (11), it can be seen that the third term is a light wave having a phase distribution conjugate with the object wave and propagating in the direction of 2θ.
In this way, the complex amplitude distribution can be recorded and reproduced using the holographic technique.
In the case of the present invention, the amplitude transmittance or reflectance of the hologram is proportional to the recorded intensity distribution and is expressed by the equation (8), but the reference wave used when recording on this hologram. Is not a predetermined angle, but a light-emitting wave having a spatial distribution similar to the amplitude transmittance or amplitude reflectance of (8) is emitted from this hologram.
Therefore, the emission wave is emitted while maintaining the phase term already recorded in the hologram, regardless of the conventional principle of hologram reproduction in which the phase term recorded in the hologram is given to the reference light. Therefore, theoretically, it has a three-dimensional continuous curved light emitting surface having a spatial function including the phase difference of an object, and light is emitted from the one curved surface.

To simplify the conventional hologram reproduction principle for the transmission type, when parallel light as reference light is applied to the hologram, the parallel light is shielded in the shielding part, and the parallel light is transmitted only from the transmission part. Diffraction occurs at the boundary between the transmission part and the shielding part, receives the phase term of the object, and the entire component transmitted through the hologram is superimposed, which becomes the hologram reproduction light and reaches the observer's eyes.
In the case of the present invention, there is no parallel light as the reference light described above, and light emission on the light emitting surface provided so as to be in contact with the hologram relief (a “color change due to“ color change ”is also referred to as“ light emission ”). In the case of explaining the principle of holograms, we will use this term “light emission” in a collective manner.) The radiated light retains the phase term of the object, and due to the interference phenomenon between the radiated light. Hologram reproduction is performed.
The interference effect between synchrotron radiation without temporal and spatial coherence does not cause sufficient interference like laser light, but hologram reproduction is performed at the same level as when a hologram is illuminated with low coherent light. . For example, “natural light generated artificially” such as “fluorescent lamps” used in ordinary homes and general offices without using special light sources such as laser light. Also, it is possible to reproduce the hologram sufficiently. However, whether “natural light generated artificially” is “point light source” or “linear”. Alternatively, depending on whether it is “planar”, whether the emission wavelength is “monochromatic light”, and whether the half-value width of the emission curve is narrow, etc. "Clarity" will be greatly affected.
Since hologram reproduction is based on the principle as described above, it is preferable that reference light at the time of hologram photographing is parallel light (because complex reference light cannot be reproduced), or “hologram represented by a diffraction grating” ( The diffraction grating is preferably parallel light for both the object light and the reference light.) Further, the diffraction grating formed by electron beam drawing, such as a computer generated hologram, is precise and suitable.

Further, for the above reason, in order to make the hologram reproduction image clearer, it is necessary to give the radiation light a characteristic similar to temporal or spatial coherence, for example, the thickness of the light emitting layer. It is desirable to make the thickness thin or to narrow the emission wavelength width. Further, the excitation light source is also preferably a small shape, and a spot shape or the like is particularly suitable.
In addition, it is desirable that the wavelength difference between the excitation light that excites the light-emitting layer and the emission wavelength after the change is large. Further, when observing, the excitation light is filtered to extract only the colored light or further amplify it. It is also effective to do.
As an excitation light source, energy such as ultraviolet rays, visible rays, electron beams, X-rays and the like, and in some cases, a light source capable of emitting infrared energy can be used to emit light, etc. In order to use it for hologram authentication, it is necessary to use a light source corresponding to the photochromic thin film, and use an ultraviolet light source, a visible light source having a predetermined intensity, wavelength, and size of an illumination spot, and an infrared light source in some cases. Is preferred.
From the photochromic thin film layer provided so as to be in contact with the hologram relief surface by illumination with these light sources, more specifically, from the photochromic molecules contained in the photochromic thin film layer, the wavelength of the light source different from that of the illumination light source Luminescence and the like appear. Since the emitted light has the same spatial phase as the hologram relief and has a wavelength (emission wavelength) different from that of the illumination light source, the direction of the specularly reflected light (0th order diffracted light) by the hologram relief and the illumination light The hologram image is reproduced in a direction different from the diffraction direction by the wavelength (excitation light wavelength), that is, in the diffraction direction by the emission wavelength.

However, when the thickness of the photochromic thin film layer is distributed on the hologram surface irrespective of the hologram relief, the emission intensity distribution resulting from the thickness distribution may be reproduced in some cases. Unnecessary interference with light can occur, which can be a cause of blurring of the hologram reproduction image.
In order to eliminate this factor, the photochromic thin film layer is formed with a uniform thickness following the unevenness forming the hologram relief so that light emission of the same intensity occurs from any position on the hologram relief surface, A clear hologram reproduction image is intended.
When ultraviolet light or infrared light other than visible light is used as the illumination light (excitation light) of the hologram label of the present invention, the light is not visible to the observer, and the hologram reproduction image is seen from the place where there is no illumination light. However, even if the illumination light is temporally and spatially coherent, as a result, the hologram reconstructed image emits light through a process of excitation and light emission. Therefore, although the spatial phase of the hologram at the time of emission is included, the temporal and spatial coherence between the colored lights is small, and the hologram reproduction image is a normal laser reproduction relief hologram. It is weaker than the reproduced image by the laser beam and is unclear.
Of course, if only observing the beam-shaped diffracted light, it is easy to check its color tone and diffraction direction, and it can be used as it is to determine the authenticity, but this weak and unclear hologram reproduction. In order to enable the observer to recognize the image and accurately determine its presence, the light emission performance of the photochromic thin film is improved, and the diffraction angle is increased to increase the wavelength-diffraction angle dependency. It is necessary to increase the difference in the diffracted light diffraction angle and further reduce the thickness of the photochromic thin film layer to suppress variation in the photochromic thin film layer thickness direction and make it uniform. (Since the light emitting surface contains phase information, its spatial shape is accurately reproduced.)

Furthermore, in order to express temporal coherency, the light source is excited by a pulse laser having a light emission time of 10 ^-15 sec or less, and the time interval between pulses is set longer than the AB intermolecular transition time. It is also suitable to do. As a result, the light emitting surface of one light emission generated by one excitation pulse does not disturb the light emitting surface generated by the next excitation pulse, and the hologram generated by one light emitting surface expressed by one pulse. A clear hologram reproduction image can be observed by the graphic interference phenomenon. Of course, even if a strobe light source that is simply turned on and off in seconds is used, the viewer seems to emit light continuously. When confirming with the above, the above-described effects can be sufficiently obtained.
The photochromic thin film layer is a photochromic molecule-containing ink in which photochromic molecules are mixed into a resin or dispersed in a solvent (or water), a hologram using a gravure method, an offset method, a silk screen method, a nozzle coating method, or an inkjet method. It can be formed on the relief.
At this time, the formed photochromic thin film layer can be formed with a uniform thickness following the unevenness forming the hologram relief by adjusting the content ratio of the photochromic molecules in the ink.
The unevenness of the hologram relief is, for example, a gentle curve having an unevenness of a depth of 0.01 μm with a period of 1 μm level and can be regarded as a substantially flat surface. 1 to 10 pascals / second), exhibiting the leveling effect due to the weight of the ink, and the solid content in the ink is 10% or less, further 5% or less, for example, for a thickness of 1 μm The variation can be suppressed to 1/10 or less, and further to 1/20 or less.

Here, the photochromic thin film layer is set to the order of 1 μm. However, in order to improve the definition of the hologram reproduction image, it is also preferable to provide the photochromic thin film layer discretely. (Size) is about 1.0 μm or less, for example, 0.01 μm to 0.5 μm, more preferably 0.01 to 0.05 μm, and it is also preferable that the size is uniformly scattered in the hologram relief surface. . In the photochromic thin film layer thickness direction, 1 to 10 molecules or 1 to 10 particles are preferably arranged in units of photochromic molecules or fine particles adsorbed with photochromic molecules.
Above all, the nozzle coating method, ink jet method, and physical vapor deposition methods such as chemical vapor deposition can form a thin film only with a solvent and photochromic molecules and particles without using a resin, and are very thin as a photochromic thin film layer. It is preferable because it can be formed (photochromic molecules, particles 1 to 10 molecules, etc.). An appropriate transparent resin layer may be formed as a protective layer in order to fix the photochromic thin film thereon.
By the way, the photochromic material can be used as a hologram recording material or an optical memory recording material itself, and such applications are already known. However, these are used for holographic recording (interference fringe recording) directly on the photochromic material. Recording), and recording fine brightness and darkness on the photochromic material.
This recording is read out using a technique that does not change the photochromic molecules in the recorded area (such as irradiation with light having a wavelength that does not change).
On the other hand, the hologram label of the present invention only illuminates all uniformly formed photochromic thin film layers in a similar manner (uniformly), and generates a uniform color. The photochromic thin film layer does not require a complicated process of exposing it, and the photochromic thin film layer itself carries the hologram information in the concavo-convex shape that it “holds as its shape”, making the photochromic thin film layer uniform The hologram information can be “acquired” (meaning that “hologram reproduction information” is “acquired”) simply by forming.

The hologram relief has a period of about 1 μm, a depth of 0.01 μm, and a maximum of 0.5 μm, and by forming a photochromic thin film layer only in this recess, it can be synchronized with the period of the hologram relief. Thus, the presence or absence of a photochromic thin film layer, that is, the presence or absence of light emission can be provided.
The concave portion of the hologram relief is a concave portion when the photochromic thin film layer is formed on the hologram relief, and is the convex portion side when observed from the normal observation method, that is, from the hologram forming layer side. In order to form the light emission intensity distribution using the presence or absence of the photochromic thin film layer, it is only necessary to partially form the unevenness, and the entire recess may be filled with the photochromic thin film layer, or You may form only in a part of bottom part. However, since it is necessary to synchronize the phase distribution and the distribution to be formed, when forming a part, it is necessary to always form the same photochromic thin film “amount” at the same position. (Because this “amount” is proportional to the emission intensity.)
As a method for selectively forming the photochromic thin film layer in the concave portion, fine particles (particle diameter of 0.01 μm, etc., containing a photochromic molecule having a very small particle diameter dispersed in a solvent or the like, or adsorbed on the surface thereof are used. Ink may be used to form an ink layer on the hologram relief, and the fine particles may move from the convex portion to the concave portion under its own weight while the solvent volatilizes.
In addition, the photochromic thin film layer uniformly provided on the regular diffraction grating is provided by photolithographic exposure, development and etching in synchronism with the regular diffraction grating. Can be provided synchronously. According to this method, it is possible to control the thickness and size of the photochromic thin film layers scattered in the respective recesses, and the so-called “uniformly” can be formed on the entire relief surface.

What is formed by the above method is to include the phase information of the hologram relief in the emitted light (radiated light) described in the principle of the hologram above, and further include amplitude information synchronized with the phase information. It is.
Therefore, the hologram light information of both the phase hologram and the amplitude hologram can be included in the emitted light, and a clearer hologram can be obtained.
Thereby, the designability and authenticity determination property can be improved.
From the above-mentioned hologram principle, it is desirable that the thickness of the photochromic thin film layer is thin in order to increase the clarity of the hologram reproduction image. The thickness of the thin film layer must be 0.01 μm or more and 1.0 μm or less, and more preferably 0.01 μm or more and 0.5 μm or less.
If it is less than 0.01 μm (one particle of the minimum particle size), the emission intensity is too weak to be distinguished from noise such as stray light even if amplified using a photomultiplier tube, and exceeds 1.0 μm. The emission intensity can be sufficient for the purpose of the present invention, but the position of the curved surface carrying the phase information of the hologram relief by the emission from a plurality of particles in the thickness direction is the thickness direction. As a result, the reproduced hologram image becomes unclear.
On the other hand, the emission intensity is secured at 0.01 μm or more, and the position of the curved surface carrying the phase information is clarified by making the emission intensity 0.5 μm or less, and the hologram reproduction image becomes clear.
Since such a photochromic thin film layer is very easily deformed when the hologram label is illegally peeled off, the authenticity determination property can be further improved.

In this photochromic thin film layer or in a region where there is no photochromic thin film layer, an adhesive layer can be provided directly on the transparent resin layer to form the hologram label of the present invention.
As the transparent resin that can be used for the adhesive layer, polymethyl methacrylate, polybutyl acrylate, polyvinylidene, methyl cellulose, fluororesin, melamine resin, or a mixture thereof can be used as appropriate. Additives and other additives can be used (means an adhesive).
These adhesives are appropriately dissolved in a solvent or water and coated on the relief relief hologram relief using a coating method such as gravure printing, silk printing, or a solventless hot melt method. The thickness after drying may be 5 μm to 50 μm.
If the thickness is less than 5 μm, the adhesive strength to the adherend to which the hologram label is attached (adhesion strength or peel strength) is insufficient, and if it exceeds 50 μm, the hologram label is suitable for handling. It will be lacking.
At this time, if the thickness of the adhesive layer is substantially equal to the thickness of the [transparent substrate + transparent resin layer], the interface between the transparent resin layer and the adhesive layer is located at the approximate center of the hologram label. Deformation stress and tensile force when trying to peel off illegally tend to be shear stress or peeling force at the interface, which is preferable.
As the transparent resin used for the above-described adhesive layer, a resin having strong adhesiveness to the photochromic thin film layer or the transparent resin layer is appropriately selected.

The adhesive layer has light scattering properties, for example, transparent inorganic pigment fine particles having a high refractive index (titanium dioxide pigment: refractive index 2.70, iron oxide pearl pigment: refractive index 3.0, etc.). (Because the light passing through the adhesive layer does not contribute to “hologram reproduction”), it is possible to develop or change the color of the photochromic thin film layer. The light traveling in the direction opposite to the observation side can be diffusely reflected and attenuated, and the viscosity of the adhesive layer can be suppressed to prevent the hologram label from being blocked.
180 degree peeling strength between the adhesive layer and the photochromic thin film layer or the transparent resin layer (peeling strength is measured according to JIS Z-0237, peeling speed is 500 mm / min) is 100 g / 25 mm to 3 kg / 25 mm, In particular, it is desirable to be 300 g / 25 mm or more. When the hologram label is less than 100 mm / 25 mm, after the hologram label is attached to the adherend, when the hologram label is illegally peeled off, peeling at the interface between the adherend and the adhesive layer is likely to occur. Almost no force such as bending and pulling acts on the hologram label, and the deformation of the photochromic thin film layer is small.
Also, in terms of preventing fraud, it is desirable that the peel strength is large, but if it exceeds 3 kg / 25 mm, the label processing suitability and label sticking suitability are poor.

According to the hologram label of the present invention,
A hologram comprising a transparent resin layer having a hologram relief including a diffraction grating group corresponding to a hologram image, and a photochromic thin film layer in contact with the hologram relief on one surface of a transparent substrate The label is provided, has a hologram reproduction image with a wavelength different from the wavelength of the illumination light, and when the hologram label is illegally peeled off, the photochromic thin film layer is deformed and is not noticed by the person who made the fraud In addition, a hologram label excellent in anti-counterfeiting properties is provided in which fraudulent traces such as blurring of the reproduced hologram remain.

These are figures explaining a photochromic molecular potential curve. These are sectional drawings of hologram label A showing one example of the present invention. (Example in which the photochromic thin film layer is “formed with a uniform thickness following the irregularities that form the hologram relief”.) These are sectional drawings of hologram label A 'which shows other examples of the present invention. (Example in which the photochromic thin film layer is formed only in the concave and convex portions forming the hologram relief.) Is a process for determining an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
(Transparent substrate) The transparent substrate 1 used in the present invention can be reduced in thickness, and can withstand mechanical strength and solvent resistance and heat resistance to withstand processing when producing the hologram label A. Those having the following are preferred. Since it depends on the purpose of use, it is not limited, but a film-like or sheet-like plastic is preferable.
For example, various plastic films such as polyethylene terephthalate (PET), polycarbonate, polyvinyl alcohol, polysulfone, polyethylene, polypropylene, polystyrene, polyarylate, triacetyl cellulose (TAC), diacetyl cellulose, and polyethylene / vinyl alcohol can be exemplified. .
Among them, those having resistance to excitation light such as ultraviolet rays, for example, those containing ultraviolet absorbers may be used. Those containing an ultraviolet absorber also have an effect of preventing unplanned hologram reproduction, although it is faint due to ultraviolet rays contained in natural light or the like.
The thickness of the transparent substrate 1 is 5 to 250 μm, but when considering the visibility of the hologram reproduction image, it is preferably 5 to 50 μm, particularly 5 to 25 μm. (See Figure 2 or Figure 3.)

(Transparent resin layer having hologram relief: also referred to as hologram forming layer)
As the transparent resin material for constituting the transparent resin layer 2 (hologram forming layer 2) having the hologram relief of the present invention, various thermoplastic resins, thermosetting resins, or ionizing radiation curable resins may be used. it can. As the thermoplastic resin, acrylic ester resin (refractive index n = 1.47), acrylamide resin (n = 1.50), nitrocellulose resin (n = 1.54), vinyl acetate resin (n = 1.47). ) Or polystyrene resin (n = 1.60) or the like, and as the thermosetting resin, unsaturated polyester resin (n = 1.64), urethane resin (n = 1.60), epoxy-modified acrylic Examples thereof include a resin (n = 1.55), an epoxy-modified unsaturated polyester resin (n = 1.64), an alkyd resin (n = 1.54), or a phenol resin (n = 1.60).
These thermoplastic resins and thermosetting resins can be used alone or in combination of two or more. One or more of these resins may be cross-linked using various isocyanate resins, or various curing catalysts, for example, metal soap such as cobalt naphthenate or zinc naphthenate may be blended. Or peroxide such as benzoyl peroxide and methyl ethyl ketone peroxide for initiating polymerization with heat or ultraviolet light, benzophenone, acetophenone, anthraquinone, naphthoquinone, azobisisobutyronitrile, or diphenyl sulfide good.

Examples of the ionizing radiation curable resin include epoxy acrylate, urethane acrylate, acrylic-modified polyester, etc., for the purpose of introducing a crosslinked structure into such an ionizing radiation curable resin or adjusting the viscosity, A monofunctional monomer, a polyfunctional monomer, or an oligomer may be blended and used.
In order to form the hologram forming layer 2 using the above-mentioned resin material, it can be directly formed by developing the photosensitive resin material by performing interference exposure of the hologram. It is preferable to perform molding by using a replica or a plating mold thereof as a replica mold and pressing the mold surface against the layer of the resin material.
When thermosetting resin or ionizing radiation curable resin is used, curing is performed by heating or ionizing radiation irradiation while keeping the uncured resin in close contact with the mold surface, and then cured by peeling after curing. The fine irregularities of the relief hologram can be formed on one side of the layer made of a transparent resin material. A diffraction grating forming layer having a diffraction grating formed in a pattern by a similar method can also be used as the optical diffraction structure.
A hologram relief including a diffraction grating group corresponding to a hologram image is a recording of interference fringes due to the interference of light between object light and reference light in an uneven relief shape. For example, a laser reproduction hologram such as a Fresnel hologram, There are white light reproduction holograms such as holograms, color holograms utilizing these principles, computer generated holograms (CGH), and holographic diffraction gratings. Further, like a machine readable hologram, the reproduction light may be converted into data by a light receiving unit and transmitted as predetermined information, or authenticity may be determined.

Also, a relief structure that is a hologram relief that includes a group of diffraction gratings corresponding to the hologram image, and that is precisely designed using not only an optical method but also an electron beam drawing device in order to precisely create fine irregularities. To produce more precise and complex reproduction light. The relief shape is designed to have a pitch, depth, or specific periodic shape of the unevenness according to the wavelength (range) of the light or light source for reproducing or reproducing the hologram, the direction and the intensity of reproduction or reproduction.
Furthermore, a color hologram image is formed by a diffraction grating pixel (a minimum unit of a single diffraction grating area consisting of the same diffraction grating line. A set of light emitted from these pixels as diffracted light is a single color hologram image. It is also possible to form the image by using an image processing method in which element decomposition is performed and a predetermined pixel size, grid line pitch, and grid line angle are assigned to each element and reproduced. (Not shown)
The pitch (period) of the unevenness depends on the reproduction or reproduction angle, but is usually 0.1 μm to several μm, and the depth of the unevenness is a factor that greatly affects the reproduction or reproduction intensity, but is usually 0.01 μm. ˜0.5 μm.
As in the case of a single diffraction grating, when the unevenness of exactly the same shape is repeated, as the adjacent unevenness is the same shape, the degree of interference of reflected light increases and the intensity increases, and the maximum value is reached. Converge. The blur in the diffraction direction is also minimized. When a single point of an image converges to a focal point, such as a stereoscopic image, the convergence accuracy to the focal point is improved, and a reproduced or reproduced image becomes clear.

The method of shaping (also called duplicating) the hologram relief shape is to use a master on which diffraction gratings and interference fringes are recorded in an uneven shape as a press die (referred to as a stamper). The concavo-convex pattern of the original plate can be duplicated by stacking and pressing them together by an appropriate means such as a heating roll. The hologram pattern to be formed may be single or plural.
In order to accurately reproduce the above-mentioned extremely fine shape and to minimize distortion and deformation such as heat shrinkage after replication, the original plate is made of metal and replicated at low temperature and high pressure.
A high hardness metal such as Ni is used for the original plate. This original plate is formed by depositing a Cr, Ni thin film layer with a thickness of 5 to 50 nm on the surface of a glass master or the like formed by optical photography or electron beam drawing, etc. by vacuum deposition, sputtering, etc. It can be made by peeling the metal after forming it to a thickness of 50 to 1000 μm by an electrodeposition method (electroplating, electroless plating, or even composite plating).
The duplication method uses a flat plate type or a rotary type, the linear pressure is 0.1 ton / m to 10 ton / m, and the duplication temperature is usually 60 ° C. to 200 ° C.
(Inactivation process and inactivated area)
A part of the surface of the transparent resin layer 2 having the hologram relief is subjected to “inactivation treatment” to form [inactivation-treated region] 3. (See Figure 2 or Figure 3.)
The “deactivation treatment” is, first, as “activation treatment”, carbon dioxide laser irradiation, far infrared carbon dioxide laser irradiation, 172 nm vacuum ultraviolet (VUV, excimer light) irradiation, oxygen sensitized excimer light irradiation, plasma treatment, Due to photon energy (7.2 eV), discharge energy, electron beam energy, etc. larger than the chemical binding energy of the transparent substrate outermost surface such as open plasma treatment, corona treatment, electron beam irradiation treatment, etc. Using a physical treatment such as breaking chemical bonds or absorbing ozone by atmospheric oxygen to generate ozone or directly excited oxygen and generating functional groups by this contact, such as 172 nm vacuum ultraviolet light Thus, only the outermost surface of the transparent resin layer 2 is “activated (means that the surface tension increases)”, and then the activated transparent resin layer 2 is activated. In part of the outermost surface, only the outermost surface is partially dissolved, or reacts with the activated functional group on the outermost surface to eliminate the activity of the functional group. Using an ink jet method, patterning is performed while avoiding contact with the activated surface, reacting only with the activated outermost surface portion of the transparent resin layer 2 to inactivate only that portion. Region 3 is obtained. (The active region and process are not shown.)

Among these methods, the “activation treatment” method includes a chemical treatment in which an oxidizing agent such as permanganate and peroxide is applied and then an oxidant is washed and removed, and vinyl, epoxy and the like. Chemical treatment using methacryloxy, amino, mercapto, acryloxy, isocyanate, or styryl, alkoxy oligomer type silane coupling agent, and argon beam etching treatment that is vacuum treatment, or transparent resin layer 2 partially It is also possible to use a physical treatment such as using an etching solution treatment that dissolves in only the modification of the outermost surface of the transparent resin layer 2.
Furthermore, as solvents to be used, ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, diacetone alcohol, isophorone, diisobutyl ketone, etc.), alcohols (methanol, ethanol, isopropyl alcohol, n-propyl alcohol, isobutyl) Alcohol, n-butyl alcohol, etc., and its aqueous solution.), Aromatics (benzene, toluene, xylene, Solvesso No. 100, Solvesso No. 150, Cactus P-180, etc.), cyclic hydrocarbons (cyclohexane, etc.) ), Esters (ethyl acetate, butyl acetate, isobutyl acetate, propylene glycol monomethyl ether acetate, cellosolve acetate, ethyl-3-ethoxypropionate, etc.), ethers (tetrahydrophenol) , Methyl cellosolve, ethyl cellosolve, butyl cellosolve, t-butyl cellosolve, etc.), etc.) for the region forming “inactivated region 3” by using a letterpress printing method or an ink jet method. A pattern is formed while avoiding contact with the substrate, and reacts with “only the activated outermost surface portion of the transparent resin layer 2” in that region to inactivate only that portion.

At this time, since the solvent does not volatilize instantaneously and it is necessary to remain on the surface of the transparent resin layer 2 for a predetermined time, the boiling point is adjusted to 60 degrees or more and 200 degrees or less, preferably 100 degrees or more and 160 degrees. . This method hardly affects the hologram relief of the transparent resin layer 2 (particularly, the accuracy of the “relief” curve), and changes only the properties of the outermost surface.
By this inactivation treatment, the surface tension of the inactivated region 3 of the hologram relief surface of the transparent resin layer 2 having the hologram relief is set to 22 mN / m to 40 mN / m (wet tension test mixed solution [wetting reagent]). The other area is set to 41 mN / m to 73 mN / m.
And the ratio of the magnitude | size of the surface tension of the area | region 2 and the area | region other than the deactivation process shall be 1 / 1.5-1/3.
If this ratio is greater than 1 / 1.5, the difference in peel strength between the two regions becomes small, and deformation of the photochromic thin film layer 4 is difficult to occur. If it is less than 1/3, deformation of the photochromic thin film layer 4 occurs. However, it is physically difficult to obtain a combination of the transparent resin layer 2 and its surface treatment method that expresses such a large difference.
“Deactivation treatment” with silicone resin or the like is performed by forming a photochromic thin film layer 4 on the transparent resin layer 2, making the photochromic thin film layer 4 into a “precise hologram relief shape”, and then on the photochromic thin film layer 4. The silicone resin or the like is provided on the surface, and an easily peeling portion is provided at the interface between the photochromic thin film layer 4 and the adhesive layer 5. (Not shown)
Of course, it is possible to perform the same inactivation treatment as the transparent resin layer 2 on the photochromic thin film layer 4.
Furthermore, the purpose of this “deactivation treatment” is to develop a difference in adhesive strength (peel strength) between one part and the other part at the interface between the transparent resin layer 2 and the photochromic thin film layer 4. For this purpose, even when a photochromic thin film layer 4 having a low adhesive strength with the transparent resin layer 2 is laminated on the transparent resin layer 2 having a large surface tension, a part of the transparent resin layer 2 is inactive. As a result, even if the value of the surface tension itself after the deactivation treatment is larger than that described above, the bonding strength of the portion at the interface between both layers is very small. Thus, the object of the present invention is achieved.
Then, the region 3 to be deactivated, that is, “a portion of the hologram relief surface that has been deactivated” is defined as “a collection of fine pattern shapes”, whereby the photochromic thin film layer 4 Generate deformation more efficiently. (Not shown)

As the “shape” of the “fine pattern shape”, a “shape” such as a halftone dot shape, a checkered pattern shape, a random pattern or the like can be used, but these “collections of fine pattern shapes” ( In order to set the “inactive area 3”, it is necessary to inactivate only the inner part of each “shape” of the “fine pattern shape”.
For this purpose, the entire outermost surface of the transparent resin layer 2 is uniformly “activated” by the above-described method, and then “inactive” is applied only to the inner region of each “fine pattern shape”. It is preferable to perform the “activation process” to be “deactivated area 3”. (Not shown)
In particular, the “shape” of the “fine pattern shape” does not need to be precisely formed (meaning that individual sizes and shapes do not need to be the same with high accuracy), and thus the above-described solvent. By controlling the opening and closing of the laser irradiation shutter and the scanning speed by an optical method such as carbon dioxide laser irradiation or the like, the “fine pattern” The unprocessed area (corresponding to the inactivated area 3) can be made into a collection (aggregate) of “fine pattern shapes”.
Therefore, the individual size of the “fine pattern shape”, that is, the individual size of the inactivated region 3 is 50 μm to 300 μm. Preferably, it is 100 micrometers-300 micrometers.

By this inactivation treatment, the inactivated region 3 may have a peel strength between the transparent resin layer 2 and the photochromic thin film layer 3 of 0.01 kg / 25 mm width or more and 0.1 kg / 25 mm width or less. After the hologram label A or hologram label A ′ is once attached to the adherend (not shown. For example, when the peel strength between the adhesive layer 5 and the adherend is 1 kg / 25 mm) The peel strength between the transparent resin layer 2 and the photochromic thin film layer 3 in the inactivated region 3 is 1/10 to 1/100.) How to remove this Even if it is devised, the inactivated region 3 always peels between the transparent resin layer 2 and the photochromic thin film layer 3 to generate voids and deformation of the photochromic thin film layer 3. .
This deformation cannot be visually recognized because the photochromic thin film layer 3 is transparent or white, and of course, even if it is colored, it is difficult to visually recognize and has a wavelength suitable for the photochromic material used for the photochromic thin film layer 3. Only after irradiation with illumination light, a hologram reproduction image that is unclear from the original hologram reproduction image, a hologram reproduction image that is distorted, and uneven coloring or discoloration can be confirmed.
The reduction in the sharpness of the hologram reproduction image is caused by the material used for the transparent resin layer 2, the photochromic thin film layer 3 and the adhesive layer 5 having the hologram relief, the forming method, the physical characteristics and optical characteristics of the layer, Depends on the direction in which the hologram label A or A ′ is peeled off and the magnitude and speed of the force to be peeled off, but by the peeling method according to JIS Z-0237 (peeling speed 500 mm / min), diffraction of the diffraction grating In terms of efficiency, it corresponds to a reduction of 10% to 30%.
If the decrease is less than 10%, the “judgment accuracy” when confirming the trace of the peeling action is uncertain. Moreover, if the reduction is more than 30%, it is physically difficult to realize it, and there is a possibility that some sort of abnormality is detected even by unauthorized persons.

(Photochromic thin film layer)
In the present invention, the photochromic thin film layer 4 is formed on the hologram relief surface of the hologram forming layer 2.
As photochromic molecules (photochromic materials) used for the photochromic thin film layer 4, there are an organic compound type and an inorganic compound type.
As an organic compound system,
Azobenzenes (cis-trans isomerism): dimethylaminoazobenzenes, etc.
Spiropyrans (intramolecular ring-opening): spirobenzothiopyran, spiroselenazolinobenzopyran, spirobenzoselenazolinonaphthoxazine, etc. More specifically, 1,3,3-trimethylindolino-6 ′ -Nitrobenzopyrospirane, 1 ', 3'-dihydro-8-methoxy-1', 3 ', 3'-trimethyl-6-nitrospiro [2H-1-benzopyran-2', 2 '-(2H)- Indole], 1,3,3-trimethylindolinobenzopyrospirane, 1,3,3-trimethylindolino-6'-bromobenzopyrrirospirane, 1,3,3-trimethylindolino-8'-methoxy Benzopyrospirane, 1,3,3-trimethylindolino-β-naphthopyrilospirane, etc.
Spirooxazines (intramolecular ring-opening): Spiroquinoxazines, spironaphthoxazines, spirophenanthrooxazines, spirobipyridoxazines, etc., compounds having a heterocyclic structure containing a nitrogen atom in the molecule Etc. (red purple to blue. “Coloring” quickly disappears)
Spiroperimidines: 2,3-dihydro-2-spiro-4 '-[8'-aminonaphthalen-1'(4'H) -one] perimidine, 2,3-dihydro-2-spiro-7 '-[8 '-Imino-7', 8'-dihydronaphthalene-1'-amine] perimidine, etc.

Arylethenes: symmetrical diarylethene, asymmetrical 2,3-diarylmaleic anhydride, asymmetrical diarylperfluorocyclopentene, etc.
1,2-bis (2,4-dimethyl-5-phenyl-3-thienyl) -3,3,4,4,5,5-hexafluoro-1-cyclopentene, 1,2-bis [2-methylbenzo [ b] thiophen-3-yl] -3,3,4,4,5,5-hexafluoro-1-cyclopentene, 2,3-bis (2,4,5-trimethyl-3-thienyl) maleic anhydride 2,3-bis (2,4,5-trimethyl-3-thienyl) maleimide, cis-1,2-dicyano-1,2-bis (2,4,5-trimethyl-3-thienyl) ethene, etc. More specifically, color development wavelength: 425 nm, 469 nm, 526 nm, 534 nm, 550 nm, 562 nm, 578 nm, 583 nm, 611 nm, 620 nm, 628 nm, 665 nm, 680 nm, 828 nm, etc. Color development)
Frugides: Diphenyl fulgide, triphenyl fulgide, etc.
Chromenes: 6-morpholino-3,3-bis (3-fluoro-4-methoxyphenyl) -3H-benzo (f) chromene, 6-morpholino-3- (4-methoxyphenyl) -3- (4-tri Fluoromethoxyphenyl) -3H-benzo (f) chromene, 6-piperidino-3-methyl-3- (2-naphthyl) -3H-benzo (f) chromene, 6-piperidino-3-methyl-3-phenyl-3H -Benzo (f) chromene, 6-morpholino-3,3-bis (4-methoxyphenyl) -3H-benzo (f) chromene, 6-hexamethyleneimino-3-methyl-3- (4-methoxyphenyl)- 3H-benzo (f) chromene, 6-morpholino-3- (2-furyl) -3-methyl-3H-benzo (f) chromene, 6-morpholino-3- (2-thienyl) -3 Methyl -3H- benzo (f) chromene, 6- morpholino-3- (2-benzofuryl) -3-methyl -3H- benzo (f) chromene, etc. (colored orange-yellow.),

Cyclophanes: Anthracene-containing cyclophanes such as anthracenophanes, anthracenonaphthalenophanes, anthracenoparacyclophanes, metacyclophanes, etc.
Chalcone (1,3-diphenyl-2-propen-1-one) -flavylium, etc.
Fulgimide compounds: N- cyanomethyl-6,7-dihydro-4-methyl-2-phenyl-spiro (5,6-benzo [b] thiophene-dicarboximide -7,2- tricyclo [3.3.1.1 ^{3 , 7} ] decane), N-cyanomethyl-6,7-dihydro-2- (4′-methoxyphenyl) -4-methylspiro (5,6-benzo [b] thiophenedicarboximide-7,2-tricyclo [3 3.1.1 ^3,7 ] decane), N-cyano-6,7-dihydro-4-methyl-2-phenylspiro (5,6-benzo [b] thiophenedicarboximide-7,2-tricyclo [3.3.1.1 ^3,7 ] decane), N-cyano-6,7-dihydro-4-methylruspiro (5,6-benzo [b] furandcarboximide-7,2-tricyclo [3.3 .1.1 ^3,7 Decane), N- cyano-4-cyclopropyl-6,7-dihydro-spiro (5,6-benzo [b] flange carboximidoyl -7,2- tricyclo [3.3.1.1 ^{3, 7]} decane) N-cyano-6,7-dihydro-4-methylspiro (5,6-benzo [b] thiophenedicarboximide-7,2-tricyclo [3.3.1.1 ^3,7 ] decane), N- Cyanomethyl-4-cyclopropyl-6,7-dihydrospiro (5,6-benzo [b] thiophenedicarboximide-7,2-tricyclo [3.3.1.1 ^3,7 ] decane), N-cyanomethyl -4-cyclopropyl-6,7-dihydro-2- (4'-methoxyphenylspiro (5,6-benzo [b] thiophenedicarboximide-7,2-tricyclo [3.3.1.1 ^{3, 7]} decane), N- Anomechiru 4-cyclopropyl-6,7-dihydro-2-phenyl-spiro (5,6-benzo [b] thiophene-dicarboximide -7,2- tricyclo [3.3.1.1 ^{3, 7]} decane) N- (3′-cyanophenyl) -6,7-dihydro-4-methyl-2- (4′-methoxyphenyl) spirobenzothiophenecarboximide-7,2′-tricyclo [3.3.1.1 ^3,7 ] Decane (colored orange to blue),

Thioindigos (cis-trans isomerism), salicylidene anilines (intramolecular hydrogen transfer: crystal type), nitrobenzylpyridines (intramolecular hydrogen transfer: crystal type), tetrachloro-α-ketodihydronaphthalene, bis (Triphenylimidazolyl) s, tetraphenylhydrazines, beanthrones, pyridylside nonones, anthracene derivatives (photodimerization), methylene blue (photoredox), triphenylmethanes (ion dissociation), hexaphenylbiimidazole (radicals) Dissociation), polycyclic aromatic compounds (oxygenation), etc.
Can be used.

In particular, a product obtained by dispersing diarylethenes in a transparent resin and a crystallized product of diarylethenes are excellent in physical properties and weather resistance.
As an inorganic compound system,
Ternary compounds selected from AgBr, AgCl, AgI, CuBr2, CuCl2, CuCl, CuI2, CuI, Ag alone, Cu alone, etc.
Silver nanoparticles-titanium oxide, etc.
Can be used.
Furthermore, among these photochromic molecules (materials), it is preferable that the emission intensity curve (wavelength as a horizontal axis) as the photochromic molecule B has only one peak in the visible region, A half-width of the peak of 10 to 50 nm is preferable because it gives a clearer hologram reproduction image.

As a forming method, it is possible to use a general printing method, a coating method, etc., but as a method for forming a more precise thin film, a spin coating method, a casting method, a screen printing method, a blade coating method, a roll coating method. , Water surface development method, LB (Langmuir-Blodget) method and the like, and dry process include vacuum deposition method, sputtering method, chemical vapor deposition method and the like.
In particular, chemical vapor deposition is suitable for forming a thin film of an organic compound system uniformly and at the molecular level.
More specifically, a resin-dispersed ink in which photochromic molecules are uniformly dispersed in a transparent resin or a solvent-dispersed ink in which photochromic molecules are dispersed in water or a solvent are prepared, and using them, a printing method or The photochromic thin film layer is formed by using various forming methods such as a coating method and an ink jet method so that the hologram forming layer 2 is in contact with the hologram relief and is uniformly tracked or partially in the recess. 4 can be formed. (See Figure 2 or Figure 3.)
In addition, it is preferable to form the photochromic thin film layer 4 directly on the hologram relief surface of the hologram forming layer 2 by chemical vapor deposition from the hologram relief followability and uniformity thereof, This is preferable because there is no collision of a high-temperature electron beam in the heating vacuum deposition method and argon atoms in the sputtering method, and the molecular structure is easily maintained.
In addition, after the photochromic thin film layer 4 is formed on the hologram forming layer 2, it is aligned with the diffraction grating pattern by photolithography using a photoresist, exposed to light, developed, and unnecessary photoresist is removed to remove the photoresist pattern. The photochromic thin film layer can be removed by etching in synchronization with the concave portion of the pattern, and the photochromic thin film layer can be left only in the concave portion. (See Figure 3.)
On the contrary, a photoresist layer is formed on the hologram forming layer 2, aligned with the diffraction grating pattern, exposed to light, developed, and removed unnecessary portions to leave the photoresist on the convex portions and expose the concave portions. After forming the photochromic thin film layer, the photochromic thin film layer 4 can be left only in the concave portion by removing the photoresist on the convex portion and at the same time partially removing the photochromic thin film layer immediately above the photochromic thin film layer. (See Figure 3.)

Resin-dispersed ink includes the above-described photochromic molecule, a transparent resin, for example, an acrylic ester resin, an acrylamide resin, a nitrocellulose resin, or a polystyrene resin as a thermoplastic resin, and as a thermosetting resin, Ball mill using glass beads and steel beads to reduce secondary aggregation by mixing in unsaturated polyester resin, acrylic urethane resin, epoxy-modified acrylic resin, epoxy-modified unsaturated polyester resin, alkyd resin, phenol resin, etc. , Kneading with a kneader, roll mill, etc., adjusting the viscosity with a solvent, etc., and using a gravure method, offset method, silk screen method, curtain coating method, nozzle coating method, and even an inkjet method as appropriate. Form to thickness Rukoto can.
However, in order to set the thickness of the photochromic thin film layer 4 to 0.003 μm or more and 1.0 μm or less, and further 0.01 μm or more and 0.5 μm or less, the solid content of the resin dispersed ink is set to 1 to 10%. When the coating film using a solvent or water as a solvent is, for example, 5 μm, the thickness after evaporation of the solvent (the thickness of the photochromic thin film layer) is 1/10 to 1/100. Thus, the thickness is set to 0.5 μm to 0.05 μm.

Since the solvent-dispersed ink does not include a resin component and includes only photochromic molecules and a solvent, the photochromic thin film layer 4 can be made thinner than the resin-dispersed ink.
As the solvent, water or an alcohol solvent, or a cellsolve or paraffin solvent is used in accordance with the polarity of the photochromic molecule to be used, and the photochromic molecule is dissolved and retained, and the hologram is applied by curtain coating, nozzle coating or the like while stirring. It can be provided on the formation layer 2.
Furthermore, several μm of a slow volatile solvent having solubility is applied to the transparent resin layer 2 forming the hologram relief surface (a ketone solvent for acrylic, polyvinyl chloride, vinyl acetate resin, polyester resin, etc.) For example, cyclohexanone, etc. This solvent can be diluted with an insoluble solvent and the remaining component can be made 0.1 μm or less.) Only the outermost surface of the hologram relief surface is dissolved. There is also a method for forming a photochromic thin film layer that imparts adhesiveness to the outermost surface and sprays photochromic molecules as a mist on the outermost surface so that only the photochromic molecules in contact with the adhesive surface remain on the hologram relief surface. Is preferred.
According to this method, the photochromic thin film layer 4 becomes a molecular level film like an LB film, is uniformly formed on the hologram relief surface (compared to the size of the hologram relief), and excitation light from the hologram forming layer 2 side. The light emitting surface when applied is “same” as the hologram relief surface.
In any case, since the unevenness of the hologram relief is very small, the photochromic thin film layer 4 has a uniform thickness and the photochromic molecules in it have a uniform density or evenly on the hologram relief surface. In order to form (in the case of partial formation, the formed parts are uniform), it is necessary to prevent photochromic molecules from aggregating into secondary particles, and a method of dissolving in a solvent (solvent) Alternatively, it is preferable to form a thin film as a nanoparticle pigment by adsorbing to the surface of the nanoparticle.
Furthermore, in order to physically protect such a very thin photochromic thin film layer 4, the above-described transparent resin may be provided with a thickness of 1.0 μm to 3.0 μm using an appropriate formation method. .
In addition, the hologram forming layer 2, the photochromic thin film layer 4, and the protective layer have a refractive index difference of 0.1 or less, or 0.03 or less, so that an unnecessary hologram before excitation can be obtained. It is possible to prevent the appearance of a reconstructed image and further improve the forgery prevention property.

(Adhesive layer)
An adhesive layer 5 is provided on the photochromic thin film layer 4 or on the hologram relief of the transparent resin layer 2.
In the latter case, since the interface between the relief hologram of the transparent resin layer 2 and the adhesive layer 5 has a concavo-convex shape of the hologram relief, the refractive of the adhesive layer 5 is suppressed for the purpose of suppressing the appearance of an unnecessary hologram reproduction image. The refractive index is the same as the refractive index of the transparent resin layer 2 or the refractive index difference is 0.1 or less.
As transparent resins (that is, adhesives) that can be used for the adhesive layer 5, polymethyl methacrylate (refractive index n = 1.49), polymethyl acrylate (n = 1.47), polybenzyl methacrylate (n = 1.57), polybutyl acrylate (n = 1.44), polyvinylidene (n = 1.42), polyisobutyl acrylate (n = 1.48), cellulose nitrate (n = 1.54), methyl cellulose (n = 1.50), cellulose acetate propionate (n = 1.47), polystyrene (n = 1.60), polyethylene terephthalate (n = 1.64), polyvinyl acetate (n = 1.47), Polyvinyl chloride / vinyl acetate (n = 1.54), fluororesin (n = 1.32), melamine resin (n = 1.56), polycarbonate (n = 1.5 ), Epoxy resin (n = 1.60 to 1.65), phenol resin (n = 1.60), thiourethane resin (n = 1.5-1.75), vinyl acetate resin (n = 1.47) ), Acrylic resin (n = 1.45), vinyl acetate-acrylic copolymer (n = 1.48), vinyl acetate-vinyl chloride copolymer (n = 1.54), ethylene-vinyl acetate copolymer , Polyurethane resin (n = 1.60), thiourethane resin (n = 1.55 to 1.75), natural rubber (n = 1.52), chloroprene rubber (n = 1.35 to 1.56) Etc.) or a mixture thereof can be used as appropriate.

In addition, both solvent-based and water-based adhesives can be used, and in particular, they can be dissolved or swollen in the material constituting the transparent resin layer 2 and the photochromic thin film layer 4 (slight dissolution) The water-based one having less influence on the hologram reproduction image even if swelling is more preferable.
Natural latex such as natural rubber latex, natural rubber latex obtained by graft polymerization of natural rubber with styrene, especially methacrylic acid methyl, in particular, to make natural material composition You may use what was produced from the raw material, and also compare acrylic resin, polyester resin (n = 1.60), polyamide resin (n = 1.53), or these rubber modified products Those having a large internal cohesive force can be appropriately selected and used, and can be used alone or in a mixed system of two or more, and further added with a plasticizer and other additives as necessary.
These adhesives are appropriately dissolved in a solvent or water, and are applied on the photochromic thin film layer 4 or on the hologram of the transparent resin layer 2 using various coating methods, silk screen printing methods, hot melt methods, and the like. On the relief, the adhesive layer 5 is provided with a formation thickness after drying of 5 μm to 50 μm to obtain a hologram label A or A ′.

When the hologram label A or A ′ created in this way is observed under illumination light [visible light (illumination light) 6] such as room illumination, the hologram reproduction image (not reproduced) 7 is observed. Not (in the case of ultraviolet excitation type),
Excitation light suitable for the photochromic molecule used, for example, ultraviolet light (wavelength 365 nm, wavelength 245 nm, etc., illumination light) 8 is irradiated at an intensity of 10 μW / cm 2 to 10 mW / cm 2 for 1.0 to 100 seconds, Alternatively, for those that change color tone in the visible region, LED light or semiconductor laser light (this becomes excitation light, that is, illumination light 8) close to a predetermined wavelength is irradiated to obtain a predetermined color tone. The authenticity can be determined by visually changing the color tone or changing the color tone and visually recognizing the hologram reproduction image 9 in the color tone.
At this time, the visibility may be improved or a mechanical determination may be performed using a predetermined filter, a reproduction light amplification device, or the like.
Also, the existence of a hologram reproduction image of a predetermined color tone may not be realized by a person who possesses a hologram label, that is, a person who possesses an authenticity identification object to which a hologram label is transferred or pasted. It is also suitable to devise so that the color tone disappears or returns to the original color tone promptly (within several seconds to several tens of seconds) after authenticity confirmation.

Then, the hologram label A or A ′ is stuck on stainless steel, and the hologram label A or A ′ is peeled off according to the method of measuring the peel strength, and again stuck on stainless steel. When observed in the same manner as described above, under the illumination light 6 such as room illumination, the hologram reproduction image (not reproduced) 7 is also “exfoliated” on the photochromic thin film layer 4 in the hologram label A or A ′. If a predetermined ultraviolet ray (illumination light) 8 is irradiated, a very unclear hologram reproduction image (not shown) is reproduced, and color unevenness can be visually confirmed. Can easily confirm that "the action of peeling off hologram label A or A 'has been performed".

Example 1
The transparent substrate 1 is printed on the surface of a 12 μm PET film with a hologram image position detection pattern and vertical and horizontal “seal” and “black” black letters of 1 mm thickness using an offset printing method. Then, the melamine resin composition is applied by gravure coating so as to cover it, and the mold surface of the replication mold of the relief hologram (“Luminescent” character image: see FIG. 4) is kept in contact with heat curing. Thus, a relief hologram was formed, and a transparent resin layer 2 (hologram forming layer 2) having a hologram relief of 3 μm in thickness was obtained.
The hologram relief surface has white and 5 mm x 5 mm size “open” and “sealed” characters (the width of the image line is 0.5 mm. The spacing between the vertical and horizontal characters is 1 mm). Using an excimer UV03 reformer manufactured by Excimer, the pattern was irradiated with excimer light having a wavelength of 172 nm for activation treatment. The area that has not been activated is the area 3 that has been deactivated. (See Figure 2.)
A photochromic thin film layer 4 having a thickness of 10 μm is formed on the hologram forming layer 2 by a gravure coating method using a resin dispersed photochromic molecule-containing ink (ink composition for the photochromic thin film layer 4) having the following composition. It formed so that it might contact | connect and dried to 0.1 micrometer thickness.
At this time, the peel strength between the photochromic thin film layer 4 and the hologram forming layer 2 is 0.08 kg / 25 mm width in the “inactivated region 3”, and 0. The width was 4 kg / 25 mm.
・ <Ink composition for photochromic thin film layer 4>
1,2-bis [2-methylbenzo [b] thiophen-3-yl]-
3,3,4,4,5,5-hexafluoro-1-cyclopentene Crystalline material B2629 manufactured by Tokyo Chemical Industry Co., Ltd. 0.1 part by weight Cellulose resin 1 part by weight Isopropyl alcohol 40 parts by weight Ethyl acetate 59 parts by weight

On the photochromic thin film layer 4, an adhesive composition for an adhesive layer 5 having the following composition was coated by a curtain coating method and dried to form an adhesive layer 5 having a thickness of 20 μm. Hologram label A was produced. (See Figure 2.)
・ <Adhesive composition for adhesive layer 5>
Vinyl acetate-acrylic copolymer 30 parts by weight Isophorone diisocyanate 1 part by weight Toluene 20 parts by weight Ethyl acetate 30 parts by weight Methyl isobutyl ketone 19 parts by weight This hologram label A is used for sealing an envelope, and is attached to the sealed part (Pressing with a roller of 2 kg load) When observed under room illumination light (illumination light 6), a hologram reproduction image is not observed (state 7 in FIG. 4), a 365 nm wavelength light source ( When illuminated with Hamamatsu Photonics UV-LED module LC-L2) (illumination light 8), this ultraviolet light is not visible, and a blue hologram reproduction image 9 “light emission” can be confirmed. And it was excellent in anti-counterfeiting properties. (See Figure 4.)
When the illumination was removed, the light emission reproduction image disappeared quickly and the original state was restored. (Not shown)
Further, the hologram label A was once peeled off at the interface between the pressure-sensitive adhesive layer 5 and the envelope, and then adhered again to the same position of the envelope. Similarly, when observed under the room illumination light 6, the hologram The reproduced image was not observed (state 7 in FIG. 4), and when illuminated with a 365 nm wavelength light source (UV-LED module LC-L2 manufactured by Hamamatsu Photonics), this ultraviolet light was not visible. The brightness of the hologram reproduction image has been lowered, and an unclear blue hologram reproduction image (unclear “light emission”) and coloring unevenness (“color” unevenness, in particular, “lightness” has been reduced. .), And the anti-counterfeiting property was excellent. (Not shown)

(Example 2)
A method of forming a photochromic molecule-containing ink (ink composition for the photochromic thin film layer 4) on the hologram relief formed on the hologram forming layer 2 formed in the same manner as in Example 1 is a spin coating method, and a uniform coating thickness The hologram label A of Example 2 was produced in the same manner as in Example 1 except that the thickness of the photochromic thin film layer 4 after drying was 0.02 μm. (See Figure 2.)
When this hologram label A was observed in the same manner as in Example 1, it was possible to more clearly confirm the blue hologram reproduction image 8 “light emission” and to confirm the color unevenness more clearly. As in Example 1, good results were obtained.
(Example 3)
Except that the photochromic molecule-containing ink was a solvent dispersion type having the following composition, the curtain coating method was used, and the drying speed was slow (the amount of drying energy was 1/5).
・ <Ink composition>
Crystalline material B2629 manufactured by Tokyo Chemical Industry Co., Ltd. 0.1 part by mass Methyl ethyl ketone 30 parts by mass Toluene 70 parts by mass The hologram label A ′ of Example 3 was produced. (See Figure 3.)
Since the photochromic molecule-containing ink is biased to the concave portion from the convex portion of the hologram relief, the dried photochromic thin film layer 4 is also biased to the concave portion.
When observed in the same manner as in Example 2, it was the same as in Example 2 except that a clearer hologram reproduction image could be confirmed than in Example 2 and that blurring appeared more clearly. Good results were obtained.

Example 4
Except that 2,3-dihydro-2-spiro-4 ′-[8′-aminonaphthalen-1-′ (4′H) -one] perimidine D3618 manufactured by Tokyo Chemical Industry Co., Ltd. was used as the photochromic molecule, In the same manner as in Example 1, the hologram label A of Example 4 was produced. (See Figure 2.)
Except that UV-LED manufactured by OMRON Corporation was used as the excitation illumination light 8, the color tone changed from yellow to blue when observed in the same manner as in Example 1. Good results similar to those of Example 1 were obtained except that a strong hologram reproduction image could be confirmed.
(Example 5)
Using the “color” and “same color” printing inks developed on the photochromic thin film layer 4 on the transparent substrate 1, the vertical and horizontal 20 mm × 20 mm size “sealing” and “緘” characters are offset. Using the excimer UV03 reformer manufactured by Excimer, the excimer light with a wavelength of 172 nm is irradiated on the hologram relief of the hologram forming layer 2 to scan and activate the entire surface. After that, a region on which the deactivation treatment is performed as a partial region on which the hologram relief surface is subjected to the deactivation treatment is printed using an ink jet method using the deactivation treatment solvent composition. 3. “Fine pattern shape” of 3 is formed as a halftone dot shape with a diameter of about 200 μm and a dot ratio of about 50% to make a “collection of fine pattern shapes”. Obtained a hologram label A of Example 5 in the same manner as Example 1. (See Figure 2.)
The peel strength between the photochromic thin film layer 4 and the hologram forming layer 2 at this time is 0.05 kg / 25 mm width in the “inactivated region 3”, and 0. The width was 4 kg / 25 mm.
<Solvent composition for deactivation treatment>
Isopropyl alcohol (boiling point 83 degrees) 20 parts Toluene (boiling point 100 degrees) 20 parts Butyl alcohol (boiling point 117 degrees) 30 parts Methyl isobutyl ketone (boiling point 115 degrees) 30 parts When observed in the same manner as in Example 1, Example 1 Furthermore, it was possible to confirm the unevenness of color development after the hologram label A was once peeled off by comparing it with the “color” of the characters “sealing” and “緘” very easily and clearly. Except for the above, good results similar to those of Example 1 were obtained. (Not shown)

(Comparative example)
A transparent hologram label was formed by forming a transparent reflective thin film layer of TiOx instead of the photochromic thin film layer without forming the photochromic thin film layer, and this was used as a comparative example.
When observed in the same manner as in Example 1, only a hologram reproduction image of a “light-emitting” character image is observed under room illumination light (illumination light 6), and a 365 nm wavelength light source (UVU made by Hamamatsu Photonics) is observed. -Even if the LED module LC-L2) is used for illumination (illumination light 8), the hologram reproduction image by the illumination light does not appear, and even after the hologram label is removed and pasted again, the situation remains It didn't change.
From this, it seems that it is difficult to make an advanced authentication with this hologram label beyond the presence of the hologram label.

A, A ′ Hologram label 1 Transparent substrate 2 Transparent resin layer having hologram relief (hologram forming layer)
3 Deactivated region (A partial region where only the outermost surface of the transparent resin layer having a hologram relief is deactivated. This is schematically shown by a wavy line.)
4 Photochromic thin film layer (continuous formation or partial formation)
5 Adhesive layer 6 Example of observation state: Visible light (illumination light)
7 Ditto: No reconstructed image (in the case of ultraviolet light excitation)
8 Same as above: Ultraviolet light (illumination light)
9 Same as above: Blue reproduction image

Claims (4)

A transparent resin layer having a hologram relief including a diffraction grating group corresponding to a hologram image on one surface of the transparent substrate, and a photochromic provided following the unevenness forming the hologram relief and having a uniform thickness A hologram label provided with a thin film layer and an adhesive layer,
A hologram label, wherein a part of the hologram relief surface of the transparent resin layer is inactivated.
2. The hologram sheet according to claim 1, wherein the photochromic thin film layer is formed only in concave and convex recesses forming the hologram relief.
The hologram sheet according to claim 1 or 2, wherein a thickness of the photochromic thin film layer is 0.01 µm or more and 0.5 µm or less.
  The said partial area | region where the said inactivation process of the said hologram relief surface is a collection of the fine pattern shape of a magnitude | size of 50 micrometers-300 micrometers, It is any one of Claims 1-3 characterized by the above-mentioned. The hologram label described.

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