JP2008273012A - Laminated structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laminated structure in which a part having less change in color is tuned to a color changing region like hologram by forming an uneven region depending on an optical diffraction structure and an uneven region independent to the optical diffraction structure on the same face. <P>SOLUTION: In the laminated structure, at least a color changeable layer partly formed, an unevenness forming layer having the uneven region depending on the optical diffraction structure and the uneven region independent to the optical diffraction structure, and an adhesion structure layer are successively formed on one side of a supporting substrate. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  In the present invention, a concavo-convex region formed by a light diffractive structure and a concavo-convex region not formed by a light diffractive structure are formed on the same surface, so that a layer having a small color change is synchronized in a color change region such as a hologram. Concerning structure.

In recent years, a hologram is formed on a part of a credit card or securities to prevent forgery. In addition, since the hologram has a high effect of improving the designability, it has been conventionally used by being attached to a part of a printed material or a molded product.
In many of these holograms, object light reflected from the object and light reflected from the object are condensed using an optical system such as a lens to form interference fringes on the surface of the recording medium coated with the photosensitive agent. Created by the method.

  In addition to the above method for producing a hologram with interference fringes, there is also a method for producing interference fringes on a recording surface by calculation using a computer. The hologram produced by such a method is called a computer generated hologram or CGH (Computer Generated Hologram). This computer generated hologram is produced by performing an optical interference fringe generation process by computer simulation and recording acquired image data on a medium.

In addition, a structure that reproduces the same color regardless of the viewing angle is provided by the multilayer thin film and the irregular irregularities (see, for example, Patent Document 1).
According to the technique disclosed in Patent Document 1, the width in the X direction is 500 nm or less on one main surface and is uniform compared to the Y direction, the length in the Y direction is indefinite, and the height or depth in the Z direction is 10 nm. The above-described base material formed by arranging a large number of square-shaped convex portions or concave portions in the XY direction, a high refractive index layer having a high refractive index, and a low refractive index layer having a low refractive index And a laminate that is alternately laminated in the Z direction so as to follow the main surface of the substrate.

JP 2005-153192 A

The technique disclosed in Patent Document 1 is low in cost by forming irregularities in the entire region, changing the color gradually according to the viewing angle change, and having gradual wavelength dispersion, deep hue and high reflectance. It is to provide to.
Therefore, the present invention can synchronize a portion having a small color change in a color change region such as a hologram by forming the uneven region by the light diffraction structure and the uneven region not by the light diffraction structure on the same surface. It is an object to provide a laminated structure.

  In order to achieve the above object, the first aspect of the laminated structure of the present invention is that at least a partially formed color variable layer on one side of the support substrate, the uneven region by the light diffraction structure and the light diffraction. A concavo-convex forming layer having a concavo-convex region independent of the structure and an adhesive structure layer are sequentially formed.

  The second aspect is characterized in that, in the first aspect, the color variable layer is a liquid crystal or a layer in which a high refractive index layer and a low refractive index layer are alternately formed.

  Further, the third aspect is characterized in that, in the first aspect, the uneven region not depending on the light diffraction structure has an uneven structure in which either the X-axis direction or the Y-axis direction is uniform. It is.

  The fourth aspect is characterized in that, in any of the first, second, and third aspects, a transparent reflective layer is further formed between the unevenness forming layer and the adhesive layer. .

  Further, the fifth aspect is any one of the first, second, third, and fourth aspects, wherein a peeling layer is further formed between the support base and the color variable layer, and the adhesive structure layer has a thermal layer. It is characterized in that a plastic adhesive is formed.

  In addition, the sixth aspect is any one of the first, second, third, and fourth aspects. The adhesive structure layer is formed with a pressure-sensitive adhesive, and the lowermost layer is a protection for protecting the pressure-sensitive adhesive. A base material is formed.

1) As in the first aspect of the laminated structure of the present invention, at least one color variable layer formed on one side of the support substrate, the uneven region due to the light diffraction structure, and the uneven region not due to the light diffraction structure As a result of the formation of the concavo-convex forming layer and the adhesive structure layer in sequence, the “uneven area by the color variable layer plus the light diffractive structure” part changes in color depending on the viewing angle, The “non-recessed region” portion is a portion where the color looks almost the same regardless of the viewing angle.
2) Also, as in the second aspect, in the first aspect, the color variable layer is a liquid crystal or a liquid crystal layer by alternately laminating a high refractive index layer and a low refractive index layer. In addition, existing materials such as cholesteric liquid crystal and nematic liquid crystal can be used, and an effective expression by the color change effect of liquid crystal becomes possible.
Further, if the high refractive index layer and the low refractive index layer are alternately laminated, the color variable effect can be effectively created as described above.
3) Further, as in the third aspect, in the first aspect, the uneven region that does not depend on the light diffraction structure has a uniform uneven structure in either the X-axis direction or the Y-axis direction. The reflected light can be prevented from being scattered in all directions, and the reflected light can be concentrated in the space.
4) Further, as in the fourth aspect, in any one of the first, second, and third aspects, a transparent reflective layer is further formed between the unevenness forming layer and the adhesive layer. The contrast between the uneven region by the color variable layer plus the light diffractive structure and the uneven region not by the light diffractive structure can be visually recognized more clearly.
5) Further, as in the fifth aspect, in any of the first, second, third, and fourth aspects, a peeling layer is further formed between the support base and the color variable layer, and the adhesive structure layer In this case, the laminated structure can be used as a thermal transfer sheet by forming a thermoplastic adhesive.
6) Further, as in the sixth aspect, in any of the first, second, third, and fourth aspects, the adhesive structure layer is formed with a pressure-sensitive adhesive, and further the pressure-sensitive adhesive is protected in the lowermost layer. As a protective base material is formed, it is possible to use for preventing counterfeiting by using a laminated structure freely without using an apparatus, selecting a place, and regardless of the shape of an object. be able to.

Hereinafter, the laminated structure of the present invention will be described with reference to the drawings.
1 is a diagram for explaining an example of a laminated structure of the present invention, FIG. 2 is a cross-sectional view taken along the line CC of FIG. 1, and FIG. 3 is a diagram for explaining another example of the laminated structure of the present invention. FIG. 4 is a cross-sectional view taken along the line CC in FIG. 1, FIG. 4 is a diagram for explaining the uneven region A, and FIG. 5 is a diagram for explaining an example of the uneven region B.

An example of the laminated structure of the present invention will be described with reference to FIG.
The laminated structure of the present invention has a color variable pattern 131 formed at least partially on one side of the support substrate, that is, either the front surface or the back surface of the support substrate, the uneven region A141 by the light diffraction structure, and the light. A laminated structure 1 in which an uneven forming layer having an uneven area B142 not depending on a diffractive structure and an adhesive structure layer are sequentially formed (that is, the laminated structure 1 is composed of at least “one pattern and two layers”). The laminated structure 1 is transferred to an object using a thermal transfer device, or the adhesive structure layer is composed of a pressure-sensitive adhesive layer and attached to the object by hand.
The color variable pattern 131 is a liquid crystal or a layer in which high refractive index layers and low refractive index layers are alternately stacked. Further, the uneven region B142 that does not depend on the light diffraction structure has an uneven structure in which either the X-axis (hereinafter also referred to as horizontal) direction or the Y-axis (hereinafter also referred to as vertical) direction is uniform. Further, although not shown, a transparent reflective layer is further formed between the unevenness forming layer and the adhesive layer.
In FIG. 1, the color variable pattern 131 is formed in front of the concavo-convex formation layer, and can be formed so as to overlap a part of the concavo-convex area A 141, which can be expressed more effectively.

Although not shown in the figure, a laminated structure in which a release layer is further formed between the support substrate and the color variable layer and a thermoplastic adhesive is formed on the adhesive structure layer uses a thermal transfer device as described above. Used by being transferred to the object.
In addition, in a laminated structure in which a pressure-sensitive adhesive is formed on the adhesive structure layer and a protective base material for protecting the pressure-sensitive adhesive is formed on the lowermost layer, the protective base material is peeled off as described above, and the object is handled. Attached with and used.

With reference to FIG. 2, a cross section taken along line CC in FIG. 1 will be described.
In the laminated structure 1 shown in FIG. 2, a release layer is formed between the supporting base material and the color variable layer described in FIG. 1, a thermoplastic adhesive is formed on the adhesive structure layer, and a thermal transfer device is used. It is a laminated structure that is used by being transferred to an object.
The laminated structure 1 includes, on one side of the support base 11, a peeling layer 12, a color variable layer 13, a concavo-convex formation layer 14 having a concavo-convex area A141 by a light diffractive structure and a concavo-convex area B142 not by a light diffractive structure, a transparent reflective layer 15 and a laminated structure in which the adhesive structure layer 16 is sequentially formed.
A color variable pattern 131 is partially formed on the color variable layer 13. The color variable pattern 131 may be formed in a strip shape or a pattern shape. Moreover, you may form in the state which covers a part of uneven | corrugated area | region A141.
In addition, the color variable layer 13 is a liquid crystal or a layer in which a high refractive index layer and a low refractive index layer are alternately stacked, and the uneven region B142 that does not depend on the light diffraction structure has an X axis direction and a Y axis direction. Any one of the directions has a concavo-convex structure in a uniform state (diffraction gratings having the same grating pitch, or the same grating density, or the same grating angle).
In addition, an undercoat layer can be appropriately provided at the boundary between each of the support substrate 11, the release layer 12, the color variable layer 13, the unevenness forming layer 14, the transparent reflective layer 15, and the adhesive structure layer 16.

With reference to FIG. 3, another example of the laminated structure of the present invention will be described.
The laminated structure 10 shown in FIG. 3 is a laminated structure described in FIG. 1 in which a pressure-sensitive adhesive is formed on the adhesive structure layer and a protective base material for protecting the pressure-sensitive adhesive is formed on the lowermost layer.
The laminated structure 10 includes a color variable layer 130 formed partially on one side of the support substrate 110, a concavo-convex formation layer 140 having a concavo-convex area A1401 by a light diffraction structure and a concavo-convex area B1402 not by a light diffraction structure, It has a laminated structure in which a reflective layer 150, an adhesive structure layer (pressure-sensitive adhesive layer) 160, and a protective substrate (release paper) 17 are sequentially formed.
A color variable pattern 1301 is partially formed on the color variable layer 130. The color variable pattern 1301 may be formed in a strip shape or a pattern shape. Moreover, you may form in the state which covers a part of uneven | corrugated area | region A1401.
The color variable layer 130 is a liquid crystal or a layer in which a high refractive index layer and a low refractive index layer are alternately stacked, and the uneven region B1402 that does not depend on the light diffraction structure is in the X-axis direction and the Y-axis direction. Any one of them has a uniform uneven structure.
In addition, an undercoat layer is appropriately provided at the boundary between each of the supporting substrate 110, the partially formed color variable layer 130, the unevenness forming layer 140, the transparent reflective layer 150, and the adhesive structure layer (adhesive layer) 160. Can do.

With reference to FIG. 4, the uneven | corrugated area | region A is demonstrated.
In the concavo-convex area A141, the object light reflected from the object and the reference light is condensed using an optical system such as a lens, and interference fringes are formed on the surface of the recording medium coated with the photosensitive agent. A hologram is formed.
In addition to the hologram, a diffraction grating can be formed by using a computer and forming interference fringes on the recording surface by calculation.
The hologram produced by such a method is called a computer generated hologram or CGH (Computer Generated Hologram). This computer generated hologram is produced by performing an optical interference fringe generation process by computer simulation and recording acquired image data on a medium.

An example of the uneven region B will be described with reference to FIG.
In the uneven region B142 shown in FIG. 5, the unevenness formed in a random size is formed in the Y-axis direction at intervals of the pitch “P” in the X-axis direction.
Moreover, the height of a fine convex part or the depth of a recessed part is set to 50-500 nm.

  With reference to FIG. 2, an example of a laminated structure in which the laminated structure is produced for thermal transfer will be described. Moreover, with reference to FIG. 3, an example of the laminated structure with which the laminated structure was produced as a sticker seal is demonstrated.

  In FIG. 2, the support substrate 11 can be selected from, for example, polyethylene terephthalate (polyester), polyvinyl chloride, polycarbonate, polyimide, polyamide, cellulose triacetate, polystyrene, acrylic, polypropylene, polyethylene, and the like.

As the release layer 12, for example, a UV curable ink containing silicone such as dimethylpolysiloxane or diphenylpolysiloxane is preferably used.
If the silicone content is too low, the desired peeling performance cannot be obtained. On the other hand, if the silicone content is too high, the strength of the coating is lowered.

The color variable layer 13 is patterned and partially formed.
The color variable layer 13 is formed with a patterned cholesteric liquid crystal or nematic liquid crystal whose color changes depending on the viewing angle.
The above-mentioned cholesteric liquid crystal is in an aligned state, and the incident light may have a property of reflecting only one of the left circularly polarized light and the right circularly polarized light, or one having each property may be arranged. .
A material having a property of reflecting only one of the left circularly polarized light and the right circularly polarized light may be mixed to have both polarization actions. In the case of using those having both left and right circularly polarized light, the hues of both may be the same or different from each other. Such a cholesteric liquid crystal is formed in a pattern by a printing method or the like.
For example, a cholesteric liquid crystal is used as a solvent type printing ink or an ultraviolet polymerization type ink is formed by a silk screen printing method or the like.
Although not shown, in the case of forming a cholesteric liquid crystal layer, an alignment film can also be provided on the support substrate side.
The alignment film is formed using polyvinyl alcohol resin (PVA), polyimide resin, or the like.
As the color variable layer 13, in addition to the liquid crystal described above, a multilayer stack of low refractive index layers (see JP-A-2005-153192) can also be formed.
In addition to the above, use OVI ink (Optical Variable Inks) that appears to change in two colors such as “green to blue”, “red to green”, and “gold to green” when the angle is changed. You can also.

  The concavo-convex forming layer 14 can be selected from resins such as acrylic, polystyrene, polyvinyl chloride, polycarbonate, melamine, epoxy, polyester, and urethane, and can be used alone or in combination. A thermoformable substance having a polymerizable unsaturated group or a radically polymerizable unsaturated monomer added thereto to make it ionizing radiation curable can be used.

A metal thin film such as aluminum is preferably used as the reflective layer 15. The reflective layer 15 is formed by a thin film forming method such as vacuum deposition, sputtering, or ion plating.
When the reflective layer 15 is a thin film having a refractive index smaller than that of the light diffraction structure, that is, when it is used as an opaque layer, for example, chromium, iron, cobalt, nickel, copper, silver, gold, magnesium, A metal such as lead, tin, cadmium, bismuth, titanium, zinc, or indium, or an oxide, nitride, or alloy of these metals is used.

  When the reflective layer 15 is a thin film having a refractive index larger than that of the light diffraction structure, that is, when used as a transparent layer, zinc sulfide, titanium oxide, aluminum oxide, silicon oxide, antimony sulfide, or the like is used.

  The reflective layer 15 is used in a thickness of 0.005 μm to 1 μm, preferably 0.01 μm to 0.1 μm, depending on the purpose.

  A heat-sensitive adhesive is formed on the adhesive structure layer 16. As the heat-sensitive adhesive, for example, vinyl chloride resin, vinyl acetate resin, vinyl chloride-vinyl acetate copolymer resin, acrylic resin, polyester resin, polyurethane resin, polyamide resin, modified rubber, etc. are selected as appropriate. And use it. These may be used alone or as a mixture of two or more, and may be used by adding a hard resin, a plasticizer, and other additives as necessary.

In FIG. 3, an adhesive is formed on the adhesive structure layer 160. Examples of the adhesive include acrylic resin, acrylate resin or copolymers thereof, natural rubber, styrene-butadiene copolymer, casein, gelatin, rosin ester, terpene resin, phenol resin, styrene resin, Select from malon indene resin, polyvinyl ether, silicone resin, etc.
The pressure-sensitive adhesive layer 15 is preferably used with a thickness of 3 μm to 20 μm.

  As the protective base material 17, for example, polyethylene, wax, silicon, or the like is applied to the surface of semi-bleached paper, high-quality paper, glassine paper, polyester film, or the like.

  In FIG. 3, the materials described in FIG. 2 are applied as they are to the layers other than the adhesive structure layer 160 and the protective substrate 17.

  Used in the field of design such as high-priced product packaging, pamphlets, POPs, book covers, and counterfeiting of cards such as credit cards, gift certificates, checks, bills, stock certificates, admission tickets, etc. .

It is a figure for demonstrating an example of the laminated structure of this invention. It is CC sectional view taken on the line of FIG. It is for demonstrating another example of the laminated structure of this invention. It is a figure for demonstrating the uneven | corrugated area | region A. FIG. It is a figure for demonstrating an example of the uneven | corrugated area | region B. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,10 Laminated structure 11,110 Support base material 12 Peeling layer 13,130 Color variable layer 14,140 Concavity and convexity formation layer 15,150 Reflective layer 16,160 Adhesive structure layer 17 Protective base material 131 Color variable pattern 141,1401 Concavity and convexity region A, Uneven region 142, 1402 Uneven region B, Uneven region not due to light diffraction structure

Claims (6)

On one side of the support substrate, at least a partially formed color variable layer, a concavo-convex forming layer having a concavo-convex region with a light diffractive structure and a concavo-convex region without a light diffractive structure, and an adhesive structure layer were sequentially formed A laminated structure characterized by The laminated structure according to claim 1,
The color variable layer is a layered structure in which liquid crystal or a layer in which a high refractive index layer and a low refractive index layer are alternately stacked. The laminated structure according to claim 1,
The laminated structure characterized in that the concavo-convex area not depending on the light diffraction structure is a concavo-convex structure in which either the X-axis direction or the Y-axis direction is uniform. In the laminated structure according to any one of claims 1 to 3,
A laminated structure in which a transparent reflective layer is further formed between the unevenness forming layer and the adhesive layer. In the laminated structure according to any one of claims 1 to 4,
A peeling layer is further formed between the support substrate and the color variable layer,
A laminated structure in which a thermoplastic adhesive is formed on the adhesive structure layer. In the laminated structure according to any one of claims 1 to 4,
A laminated structure, wherein a pressure-sensitive adhesive is formed on the adhesive structure layer, and a protective substrate for protecting the pressure-sensitive adhesive is further formed on the lowermost layer.

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