JP5648457B2 - Hologram medium and transfer foil - Google Patents

Description

  The present invention relates to a transfer foil and a hologram medium for attaching a hologram to a fibrous material such as clothes.

  As shown in FIG. 9, the embossed hologram has a basic structure in which a metal reflecting layer 2 is provided on a diffractive structure 1 made of resin or the like, and reflected light diffracted from the diffractive structure 1 side is visually recognized. By doing so, image expression rich in change is possible. By using such an embossed hologram attached to an article in the form of a transfer foil, for example, a product with high designability and anti-counterfeiting properties can be obtained.

By the way, when a hologram is provided on the surface of a cloth made of natural fibers such as cotton and linen, and chemical fibers such as nylon and cellulose, such as clothing, the stretchability of the fibers has been a problem.
That is, when it is provided on a substrate such as a plastic substrate, the hologram does not deteriorate even if it is applied directly through an adhesive layer because of its low elasticity. The metal reflection layer is destroyed by the stress, and the hologram becomes cloudy. In particular, as shown in FIG. 10, when the hologram is transferred from the transfer foil onto the transfer medium, the stress as shown by the arrow is applied to the hologram due to the unevenness caused by the overlap of the warp and weft of the fiber, and the metal reflection layer The problem arises that ruptures.

  As a hologram corresponding to a stretchable material, Patent Document 1 provides a hologram on a surface of cloth, synthetic leather, etc. via a stretchable resin layer, thereby buffering deformation of the material and damaging the hologram. It is reduced. However, the buffering of the stretchable resin layer can only cope with a certain degree of deformation depending on the film thickness, and if the stretch / change is large, the metal reflective layer is also destroyed, which is not sufficient.

JP 9-34342 A

  Accordingly, an object of the present invention is to provide a transfer foil that does not break even on a stretchable fibrous base material such as cloth, and a hologram medium using the same.

The invention according to claim 1 of the present invention, which has been made to solve the above problems, includes a hologram on a base material formed by periodically arranging yarns made of a single fiber or twisted fibers. A holographic medium provided with a layer,
The hologram layer includes a diffractive structure and a metal reflective layer formed on the diffractive structure, and is periodically disposed so that the metal reflective layer is parallel to the direction in which the yarn extends, and at least warp The hologram medium is characterized in that in a direction parallel to one of the weft yarns, the pitch pitch of the yarns coincides with the pitch of the pattern of the metal reflection layer.
The invention according to claim 2 of the present application is characterized in that the width of each pattern of the metal reflection layer is equal to or less than the width of the concave or convex portion of the concave and convex portions of one cycle of the yarn. The hologram medium according to Item 1.
In the invention according to claim 3 of the present application, the base material is composed of warp yarns and weft yarns orthogonal to the warp yarns, and the metal reflective layer is periodically arranged at substantially the same pitch as the pitches of the warp yarns and the weft yarns. The hologram medium according to claim 1, wherein the hologram medium is a hologram medium.
The invention according to the claims 4, between the pattern of the metal reflecting layer, Ru hologram medium der according to any one of claims 1 to 3, characterized in that the high refractive index layer is formed .

  According to the present invention, the metal reflection layer that reflects the diffracted light of the hologram layer is configured in a pattern that matches the period of the yarns that make up the cloth base material. A hologram medium in which the hologram damage is reduced without being broken.

It is a schematic diagram which shows the example of the base material which concerns on this invention. It is a cross-sectional schematic diagram which shows the structural example of the hologram layer which concerns on this invention. It is a schematic diagram which shows the example of the hologram medium which concerns on this invention. It is a schematic diagram which shows the example of the hologram medium which concerns on this invention. It is a schematic diagram which shows the example of the base material which concerns on this invention. It is a schematic diagram which shows the example of the hologram medium which concerns on this invention. It is a cross-sectional schematic diagram which shows the structural example of the transfer foil of this invention. It is a cross-sectional schematic diagram which shows another structural example of the transfer foil of this invention. It is a cross-sectional schematic diagram which shows the structural example of the conventional hologram. It is a cross-sectional schematic diagram which shows the structural example of the conventional hologram.

  1A and 1B are schematic views showing examples of a base material constituting the base material of the hologram medium of the present invention. A substrate made of periodically arranged fibers can be used. Hereinafter, this is referred to as a cloth base material. Generally, the fabric base material is a woven fabric such as plain weave, twill weave, and satin weave. Examples of the fibers include animal fibers such as wool and silk, plant fibers such as cotton and hemp, and synthetic / chemical fibers such as polyamide, polyvinyl alcohol, polyethylene, polyester, and cellulose.

  FIG. 1A shows an example of a plain weave in which warp and weft are alternately crossed. Each yarn may be composed of a single fiber, or may be an aggregate in which fibers are spun. FIG. 1B is a partial schematic cross-sectional view taken along a line parallel to the warp yarn of FIG. Thus, unevenness is caused by the intersection of the warp and the weft.

  FIG. 2 is a schematic cross-sectional view showing a configuration example of a hologram used in the hologram medium of the present invention. The hologram layer 200 includes a diffraction structure layer 201 that diffracts incident light, a metal reflection layer 202 that reflects incident light, and an adhesive layer 204 for adhering to a base material from the viewing side. Further, a high refractive index layer 203 having a refractive index larger than that of the diffractive structure layer can be provided between the metal reflective layer patterns. Even in a region where the pattern of the metal reflective layer is not formed, incident light can be reflected to improve the luminance of the hologram.

  FIGS. 3A and 3B show a configuration example of the hologram medium of the present invention in which the above-described hologram layer is bonded onto a cloth substrate via an adhesive layer. 3A and 3B, only the metal reflection layer 202 is shown as the hologram layer. In the configuration shown in FIG. 3, the metal reflection layer pattern is formed so as to coincide with the pitch (warp direction d1, weft direction d2) based on the intersection of the warp and weft of the fabric base material. In FIG. 3A, the metal reflective layer is arranged in a region where the wefts intersect on the warp line. That is, the metal reflection layer is formed so that the pitch d1 in the warp direction is substantially the same as the pitch in the direction parallel to the warp of the metal reflection layer, and is substantially the same as the pitch d2 of the weft in the direction parallel to the weft. Yes. In the configuration example of FIG. 3, as shown in FIG. 3B, the pitch d <b> 1 is taken at a cycle based on the intersection of the warp and the weft so that the metal reflection layer is arranged on the weft in the warp line. As shown in FIG. 4, the interval (d3, d4) of the arrangement of the yarns may be matched with the pitch of the metal reflection layer. The pitch of the metal reflective layer may be adjusted in a range not exceeding the dimensional change rate in consideration of the dimensional change of the cloth base material.

  In FIG. 3B, one piece of the metal reflective layer 202 is formed with a width equal to or less than the width b1 of the recess (the region where the wefts intersect on the warp). In particular, when the width is equal to the width a1 of the convex portion (the region where the weft intersects under the warp yarn) as in plain weaving, a metal reflective layer is formed across a plurality of concave portions or convex portions as shown in FIG. Therefore, accurate alignment is not required if the direction of the yarn and the pitch direction of the pattern of the metal reflecting layer are matched.

  FIG. 5 is a schematic diagram of a cloth base material in the case of twill weave. When the exposure ratio between the warp and the weft is different as in a twill weave, a metal reflective layer 202 pattern corresponding to the width a2 of the warp or the width b2 of the weft may be formed as shown in FIG. The pattern of the metal reflection layer may be formed in accordance with a small width (b2 in the figure) as in B).

  Next, each configuration of the transfer foil and the hologram medium of the present invention and a manufacturing method thereof will be described with reference to FIG.

  First, the diffractive structure layer 201 is formed on the support 301. In addition, a peelable protective layer 302 for peeling the hologram layer 200 from the support during transfer can be provided between the support layer and the diffractive structure layer.

  A resin film or sheet is used for the support 301. Examples of the resin include films and sheets made of polyethylene terephthalate resin, polyethylene naphthalate resin, polyimide resin, polyethylene resin, polypropylene resin, heat-resistant polyvinyl chloride resin, and the like. It is done.

  Among these resins, since the heat resistance is high and the thickness is stable, a sheet or film of polyethylene terephthalate resin is often used, and a thickness of about 10 to 50 μm is preferable. In addition, for these resin sheets and films, films subjected to processing such as antistatic treatment, mat processing, embossing, printing of characters and pictures, laser marking, and the like can also be used.

  The peelable protective layer 302 transfers the hologram layer 200 to a cloth base material that is a transfer target and peels it from the support. Examples of the main material of the ink as the peelable protective layer include acrylic resins. In addition, chlorinated rubber resins, nitrocellulose, acetyl cellulose, cellulose acetate butyrate, polystyrene, vinyl chloride, vinyl chloride resin, and the like can be used. Furthermore, melamine resin, alkyd resin, epoxy resin, etc. can be used, and silicone resin, paraffin wax, reactive fluorine resin, etc. can also be used. The thickness is preferably 0.5 to 5.0 μm. These are formed as the peelable protective layer 2 on the support 1 by a known coating method such as gravure printing or microgravure.

  As a material of the diffraction structure layer 201, a thermoplastic resin, a thermosetting resin, an ultraviolet ray, an electron beam curable resin, or the like can be used. For example, acrylic resins include acrylic resins, epoxy resins, cellulose resins, vinyl resins, and the like. In addition, urethane resins, melamine resins, phenol resins, and the like obtained by adding polyisocyanate as a crosslinking agent to an acrylic polyol or polyester polyol having a reactive hydroxyl group and crosslinking can be used. Further, as the ultraviolet ray or electron beam curable resin, epoxy (meth) acryl, urethane (meth) acrylate, or the like can be used, and the thickness is preferably 0.5 to 5.0 μm.

  After forming the diffractive structure layer 201 on the support layer 301, a diffractive structure is formed in the diffractive structure layer. In order to emboss the diffractive structure into the diffractive structure layer, the master plate of the diffractive structure is overlaid on the diffractive structure layer, heated and pressurized under the conditions of 90 to 150 ° C., and then cooled.

  Next, the metal reflection layer 202 is formed on the surface of the diffraction structure layer 201 on which the diffraction structure is formed. Aluminum, gold, silver, copper, and alloys containing these metals can be used for the metal reflective layer. The pattern of the metal reflective layer may be formed by etching the unnecessary portion after being formed on the entire surface, or the metal layer may be stacked and patterned simultaneously by forming the metal layer through a mask. .

  Next, the high refractive index layer 203 is formed on the metal reflective layer 202 and the diffraction structure 201 including the metal reflective layer. As a material for the high refractive index layer, tin oxide, titanium oxide, indium oxide, zinc sulfide, or the like can be used. The thickness is preferably 10 to 100 nm.

  In addition, when a high refractive index layer is unnecessary because the space between the metal reflective layers is small, a resin layer for enhancing the flexibility of the hologram layer may be formed between the metal reflective layers. Alternatively, a resin layer may be provided on the high refractive index for the same purpose. As the resin layer, the same material as that of the diffraction structure layer can be used.

  A reinforcing layer 401 that prevents the metal reflective layer from being broken may be provided on the metal reflective layer 202. As the reinforcing layer, a material having good adhesion with the metal reflective layer and a material having rigidity equal to or higher than that of the metal reflective layer is preferable. For example, metal plating, such as chromium plating, and metal oxide films, such as aluminum oxide, are mentioned. As shown in FIG. 8, the reinforcing layer is preferably formed in the same pattern as the metal reflective layer.

  The adhesive layer 204 for adhering the hologram layer to the cloth substrate includes polyester resin, acrylic resin, vinyl chloride resin, polyamide resin, polyvinyl acetate resin, rubber resin, ethylene-vinyl acetate copolymer resin, vinyl chloride. A thermoplastic resin such as an acetic acid copolymer resin can be used. The film thickness is preferably 1 to 20 μm.

  Finally, a fabric base material, which is a transfer medium, is attached to the adhesive layer 204 by thermocompression bonding, and the support 301 and the peelable protective layer 302 are separated to produce a hologram medium.

<Preparation of cloth base>
First, a cloth base material on which fibers were periodically arranged for transferring a transfer foil with a hologram was prepared. The fiber is made of polyester satin, and the dimensional change rate of the cloth base material according to JIS L1096 is 1% in both length and width. Optical fabric substrate? It observed with the microscope and the period of the periodic pattern and the width | variety of an unevenness | corrugation were measured about each direction of the warp and the weft. The measurement results were as follows.
Longitudinal direction: Repeat of 0.7 mm warp yarn exposed portion (convex portion) and 0.5 mm weft exposed portion (concave portion) (longitudinal period 1.2 mm)
Lateral direction: 0.1 mm warp yarn exposed portion (convex portion) and 0.1 mm weft exposed portion (concave portion) repeated (cycle length 0.2 mm)

<Example 1>
On one side of a transparent support made of a polyethylene terephthalate (PET) film having a thickness of 25 μm, a composition having the following blending ratio with a peelable protective layer was applied by a gravure printing method, with a coating thickness of 1.0 μm and a drying temperature of 110 ° C. It was formed by coating with.
(Peelable protective layer composition)
Acrylic resin 20 parts Ethanol 40 parts Water 20 parts

Next, as a diffractive structure layer, a composition having the following blending ratio was applied by a gravure printing method at a coating film thickness of 1 μm and a drying temperature of 110 ° C., and then a diffractive structure was formed by a roll embossing method.
(Diffraction structure layer composition)
Mixture of vinyl chloride-vinyl acetate copolymer and urethane resin 25 parts Methyl ethyl ketone 70 parts Toluene 30 parts

Next, an aluminum thin film having a thickness of 80 nm was formed on the diffractive structure layer as a metal reflective layer by vacuum deposition. Thereafter, the deposited aluminum layer was masked with a resist pattern, and the insoluble portion was etched to form the following metal reflective layer pattern.
Longitudinal direction: 0.7 mm metal reflective layer and 0.5 mm removal part (vertical direction period 1.2 mm)
Lateral direction: 0.1 mm metal reflective layer and 0.1 mm removal part (lateral period 0.2 mm)

  Next, a ZnS thin film having a film thickness of 80 nm was formed as a high refractive index layer on the diffractive structure layer surface on which the metal reflective layer was formed by a vacuum deposition method.

Next, as an adhesive layer, a composition having the following blending ratio was applied by a gravure printing method with a coating film thickness of 4.0 μm and dried at a drying temperature of 110 ° C.
(Adhesive layer composition)
Polyester resin 30 parts Toluene 50 parts Methyl ethyl ketone 50 parts A transfer foil with a hologram layer was prepared by the above steps.

  Finally, the transfer foil with hologram layer was transferred to the cloth base material so that the direction of the cloth base material coincided with the direction of the pattern of the metal reflection layer to obtain a hologram medium.

(Comparative Example 1)
A hologram medium was prepared in the same process as described above except that the metal reflective layer was not patterned.

(Comparison result)
Each of the hologram media of Example 1 and Comparative Example 1 is optical? Observed with a microscope. In the hologram medium of Comparative Example 1, breakage of the metal reflection layer was observed every several mm ² , whereas in the hologram medium of Example 1, almost no breakage of the metal reflection layer was confirmed. In addition, in comparison with the visibility of the hologram in Comparative Example 1, the hologram layer was clouded, whereas in Example 1, the pattern of the hologram layer was clearly visible.

DESCRIPTION OF SYMBOLS 1 ... Diffraction structure layer 2 ... Metal reflection layer 3 ... Transfer medium (cloth)
101..Cloth substrate 201..Diffraction structure layer 202..Metal reflection layer 203..High refractive index layer 204..Adhesive layer 301..Support 302..Peelable protective layer 401..Reinforcing layer

Claims (4)

A hologram medium in which a hologram layer is provided on a substrate composed of a single fiber or a yarn in which fibers are twisted and arranged periodically,
The hologram layer includes a diffractive structure and a metal reflective layer formed on the diffractive structure, and is periodically disposed so that the metal reflective layer is parallel to the direction in which the yarn extends, and at least warp A hologram medium, wherein a periodic pitch of the yarn and a pitch of the pattern of the metal reflection layer coincide in a direction parallel to one of the weft yarns.   2. The hologram medium according to claim 1, wherein the width of each pattern of the metal reflective layer is equal to or less than the width of the concave or convex portion of the concave and convex portions of one cycle of the yarn.   The said base material is comprised with the warp and the weft orthogonal to this warp, and the said metal reflective layer is arrange | positioned periodically with the pitch substantially the same as each pitch of the said warp and the weft. Or the hologram medium of 2. The hologram medium according to claim 1, wherein a high refractive index layer is formed between the patterns of the metal reflective layer.

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