JP4451505B2 - Transparent light diffraction pattern recording material - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a transparent optical diffraction pattern recording body suitably used for hologram seals such as a wristwatch-type calendar, forgery-preventing transfer holograms and paper-embedded holograms.
[0002]
[Prior art]
Conventionally, as a hologram product of this type, a transparent or translucent hologram forming layer that is attached to the surface of an article and can be peeled off after a lapse of a certain period of time and calendar information is recorded as a hologram image capable of reproducing white light; A pressure-sensitive adhesive layer that is formed on one surface of the hologram-forming layer and has both properties of sufficient adhesion to the surface of the article and re-peelability that can be peeled off after a certain period of time. A hologram calendar consisting of the following has been proposed (WO 91/03380).
[0003]
This hologram calendar is used by sticking it on the surface of the protective glass of a wristwatch, so it is a transparent hologram, so you can usually see the clock face and tilt it to a predetermined angle when you want to know the calendar information. The calendar information is reproduced as a hologram image.
[0004]
[Problems to be solved by the invention]
However, in the above-described conventional technique, only the image portion of the hologram is visible or invisible depending on the viewing angle, and thus further improvements in security and design have been demanded.
[0005]
An object of the present invention is to provide a transparent optical diffraction pattern recording body that can solve the above-described problems and can further improve security and design.
[0006]
[Means for Solving the Problems]
The present invention solves the above problems by the following means. In addition, in order to make an understanding easy, although it attaches | subjects and demonstrates the code | symbol corresponding to embodiment mentioned later, it is not limited to this.
That is, the invention of claim 1 is an image formed of a light selective transmission material that transmits light of a specific wavelength in the visible light region and scatters light of other wavelengths, and in which a white light reproduction type light diffraction pattern is formed. A transparent light diffraction pattern recording body comprising: an image layer (12) having a portion (12a); and a transparent or translucent reflective layer (13) formed on at least the back surface of the image portion of the image layer. .
[0007]
According to a second aspect of the present invention, in the transparent optical diffraction pattern recording body according to the first aspect, an adhesive layer (14) is formed on the opposite side of the reflective layer (13) from the image layer (12). A transparent optical diffraction pattern recording body.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in more detail with reference to the drawings and the like.
(First embodiment)
1 and 2 are diagrams showing a first embodiment of a transparent light diffraction pattern recording body according to the present invention. FIG. 1 is a sectional view schematically showing a layer structure, and FIG. It is explanatory drawing which shows the property of a permeable material.
The transparent optical diffraction pattern recording body 10 of the first embodiment includes a base material 11, an image layer 12, a reflective layer 13, an adhesive layer 14, and the like.
[0009]
The substrate 11 serves as a carrier for the transparent optical diffraction pattern recording body 10, and is intended to protect the image layer 12 and the reflective layer 13 from damage due to external force and to provide strength. Is not necessary. As the material of the base material 11, cellulose resin, polyimide resin, polystyrene resin, polyester resin, a single substance of polyolefin resin, a mixture, a copolymer, and the like can be used. As for the thickness of this base material 11, about 5-200 micrometers is preferable.
[0010]
The image layer 12 is formed with a surface uneven pattern (light diffraction pattern) capable of reproducing a two- or three-dimensional image. As this surface concavo-convex pattern, a relief hologram or a relief diffraction grating in which the intensity distribution of the interference fringe light due to the interference between the object light and the reference light is recorded as a concavo-convex pattern can be recorded, such as a Fresnel hologram, a Fraunhofer hologram, Laser reproduction holograms such as lensless Fourier transform holograms and image holograms, and white light reproduction holograms such as rainbow holograms, and color holograms, computer holograms, hologram displays, multiplex holograms, and holographic stereograms using these principles And a holographic diffraction grating using a hologram recording means. In addition, a diffracted light can be obtained based on a calculation by mechanically producing a diffraction grating using an electron beam drawing apparatus or the like. Can also be mentioned grams or a diffraction grating or the like, they may be recorded in a single or multiple.
[0011]
In addition, as a normal product, an embossed copy of the relief shape of these records can be used. This hologram image includes a diffraction pattern formed by the diffraction grating as described above.
[0012]
The image layer 12 is a layer in which an image portion 12a which is a relief surface of a hologram image is formed on the lower surface. As shown in FIG. 2, the image layer 12 transmits light of a specific wavelength (for example, blue light B) and scatters light of other wavelengths (yellow light Y that is a complementary color of blue light). It is made of a permeable material (see Japanese Patent Application Laid-Open No. 4-8768), and it is necessary to be a multiphase composite material of A phase and B phase in which at least one phase is a resin layer.
[0013]
The components of the A phase and the B phase of the image layer 12 need to be transparent or translucent, and are styrene-based, acrylic-based, vinyl chloride-based amorphous polymers, or transparent polyolefin, transparent polyester, transparent polyamide, Transparent polyimide, polycarbonate, polyurethane, silicone resin, etc. can be used. In addition to the resin, inorganic materials such as glass can be used.
[0014]
The reflective layer 13 is a layer that increases the hologram effect formed in the image portion 12a of the image layer 12. When used as a transparent light diffraction pattern recording body, the reflective layer 13 needs to have reflective transparency. Examples thereof include a transparent material having a refractive index different from that of the layer 12 and a metal thin film layer having a thickness of less than 200 mm.
In the former case, the refractive index of the reflective layer 13 may be larger or smaller than the refractive index of the image layer 12, but the difference in refractive index is preferably 0.1 or more, and the difference is 0. More preferably, it is 5 or more, more preferably 1.0 or more.
In the latter case, although it is a metal thin film, the thickness is less than 200 mm, so that the transmittance of light waves is large. Therefore, in addition to the hologram effect manifesting effect, the lower part, for example, the display part is not concealed. To do.
[0015]
Examples of the material of the reflective layer 13 include Sb ₂ S ₃ (3.0) and ZnS (2.1) as a transparent continuous thin film having a higher refractive index than the resin of the image layer 12. In order to form the reflective layer 13 on the image layer 12, a thin film forming method such as a vacuum deposition method or a sputtering method may be used.
Details of the material and manufacturing method of the image layer are disclosed in U.S. Pat. No. 4,856,857 of the present applicant.
Further, the reflective layer 13 may be a metal thin film having a thickness of 200 mm or more. In this case, the image layer 11 exhibits a silver color.
[0016]
The pressure-sensitive adhesive layer or the adhesive layer 14 is for attaching the transparent light diffraction pattern recording body 10 to an article. In this example, an appropriate one can be selected and used from general adhesives or adhesives such as acrylic, rubber and EVA. When protecting the adhesive layer 14 before use, it is preferable to attach a release paper (not shown) and peel the adhesive layer 14 from the adhesive layer 14 during use. As the release paper, one obtained by applying a silicone resin, wax, paraffin or the like to a base material such as paper or film can be used.
[0017]
FIG. 3 is a diagram for explaining the operation of the transparent optical diffraction pattern recording body according to the first embodiment.
The transparent light diffraction pattern recording body 10 according to this embodiment changes depending on the viewing angle of the image portion 12a, as in the conventional transparent light diffraction pattern recording body. That is, when viewed from a predetermined angle at which the hologram is reproduced (E1), the image portion 12a can be viewed, and when viewed from another angle (E2), the image portion 12a cannot be viewed. .
[0018]
Also, scattered light of different colors can be obtained depending on the angle viewed from other than the image portion 12a. That is, the image portion 12a appears bluish by transmitted light when the angle is reproduced as a hologram (E1). On the other hand, the image portion 12a appears to be yellowed by scattered light even when the angle is not reproduced as a hologram (E3). Therefore, the image portion 12a appears to be positive or negative depending on the viewing angle.
[0019]
Further, the color appears different when viewed from the light source side (E1) and when viewed through the light (E4).
[0020]
(Second Embodiment)
FIG. 4 is a cross-sectional view schematically showing a layer structure of a second embodiment of the transparent optical diffraction pattern recording body according to the present invention.
The transparent light diffraction pattern recording body 10B of the second embodiment includes a base material 11B made of a material having selective light transmission and an image layer 12B made of a normal transparent or translucent resin. The adhesive layer 14 is the same as in the first embodiment. In the second embodiment, the same operation and effect as in the first embodiment can be obtained.
[0021]
(Deformation)
The present invention is not limited to the embodiment described above, and various modifications and changes are possible, and these are also within the equivalent scope of the present invention.
(1) In the case of the second embodiment, the image layer 12 is formed on the base material 11 by a coating method or the like. However, if the base material 11 can be embossed, the image layer 12 itself has a relief hologram or the like. A hologram image may be formed. In this case, the image layer 12 is not necessary. That is, the base material 11 can also serve as the resin layer of the image layer 12.
[0022]
(2) The transparent optical diffraction pattern recording material can be used as a forgery prevention medium for securities, cash vouchers, certificates, etc. in addition to a wristwatch-type calendar.
[0023]
【The invention's effect】
As described above in detail, according to the present invention, since the light selective transmission material is used for the base material or the image layer, in addition to the effect that the image portion of the light diffraction pattern changes depending on the viewing angle, it is viewed from the light source side. In this case, an effect of different colors can be obtained when viewed through light.
Further, by scattering the specific wavelength component of the reflected light of the image portion of the light diffraction pattern, the scattered light can be obtained in different colors by changing the viewing angle from the portion other than the image portion of the light diffraction pattern.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view schematically showing a layer structure of an embodiment of a transparent light diffraction pattern recording body according to the present invention.
FIG. 2 is an explanatory view showing properties of a light selective transmission material of an embodiment of a transparent light diffraction pattern recording body according to the present invention.
FIG. 3 is a diagram illustrating the operation of the transparent light diffraction pattern recording body according to the present embodiment.
FIG. 4 is a sectional view schematically showing a layer structure of a second embodiment of a transparent light diffraction pattern recording body according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10,10B Transparent type | mold optical diffraction pattern recording body 11, 11B Base material 12, 12B Image layer 12a Image part 13 Reflective layer 14 Adhesive layer or adhesive layer

Claims (2)

An image layer having an image portion that is made of a light selective transmission material that transmits light of a specific wavelength in the visible light region and scatters light of other wavelengths, and in which a white light reproduction type light diffraction pattern is formed;
A transparent optical diffraction pattern recording body comprising: a transparent or translucent reflective layer formed on at least the back surface of the image portion of the image layer. The transparent light diffraction pattern recording body according to claim 1,
An adhesive layer is formed on the opposite side of the reflective layer from the image layer;
A transparent optical diffraction pattern recording body characterized by the above.

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