JP2648593B2 - Method of manufacturing transfer hologram - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a volume phase hologram capable of observing a three-dimensional image on, for example, a flat film, and more particularly to a method for transferring a holographic image to a desired place by transfer. The present invention relates to a method of manufacturing a transfer hologram that can be provided simply and easily.

[Conventional technology]

Holography irradiates an object with a wave of light with good coherence like a laser, and receives and records reflected or transmitted light whose amplitude and phase are modulated according to the shape of the object with a sensitizer, This is a technique for reproducing an optical image of an object recorded by light applied to a formed hologram. For example, a stereoscopic optical image can be observed on a flat film.

With the progress of such holographic research, the demand for sensitizers has become quite clear. As sensitizers that can be used for holography, many materials such as a bleached silver salt, a photoresist, a thermoplastic, a gelatin dichromate, an inorganic glass-based material, and a ferroelectric material are known. Has been studied.

The properties that the sensitizer for hologram formation should have are, for example, (1) laser sensitivity, particularly having a laser sensitivity in the visible light region and high sensitivity, (2) having high resolution, (3) The diffraction efficiency of the obtained hologram is high, (4) the noise of the hologram is small, (5) the hologram is stable, and (6) the recording and reproducing operations are easy. it can.

On the other hand, with the progress of holography technology, it is becoming possible to form holograms that can withstand practical use, and the applications of holograms are expanding in various directions, such as enjoying images themselves and using them to decorate various objects Therefore, various forms corresponding to the hologram are being demanded.

For example, a hologram that forms irregularities corresponding to the image on the surface of the photosensitive layer and reproduces the image by using the reflection or transmission of light at the irregularities is used as a book cover or forgery or falsification of a magnetic card. It is already used as a mark for prevention.

[Problems to be solved by the invention]

However, a hologram capable of sufficiently responding to the various demands accompanying the expansion of applications as described above has been provided, both in the characteristics of the hologram-forming sensitizer described above and in the form of the hologram itself. There is no present.

For example, a technique of easily applying a hologram to various desired objects by a simple operation, and a form of a hologram suitable for the technique have not yet been provided.

The present invention has been made in view of the response to various demands accompanying the expansion of the use of such holograms, and has as its object to provide a technology that facilitates application of holograms to various objects. I do.

[Means for solving the problem]

The above object can be achieved by the present invention described below. That is, the present invention is directed to the production of a transfer type hologram in which a hologram-forming photosensitive layer provided on a transparent substrate so as to be peelable is subjected to hologram exposure and development with an organic solvent to form a reflective volume phase hologram. The method, between the substrate and the hologram-forming sensitizer layer, having solvent resistance to the organic solvent used in the development process, and a specific absorption band in the wavelength range of 400 to 800 nm. A hologram-forming sensitizer layer further comprising a vinylcarbazole-based polymer.

By using the transfer type hologram obtained in the present invention, by a simple operation of transferring the hologram film held on the base material to a desired article, a desired holographic image can be formed from paper, metal, plastic, ceramic, or the like. It can be easily applied to desired portions of various objects (hereinafter, referred to as a transfer-receiving material). In addition, for example, a hologram film can be transferred onto a transfer medium by using a suitable backing paper and enjoyed in the same way as a picture or a photograph.

In the above-described type using the uneven surface, when a hologram is directly adhered to various types of transfer-receiving materials by pressure bonding or adhesion, the influence of deformation or breakage on the irregularities formed on the surface is inevitable. Since the volume hologram film is used for the transfer type hologram in the above, such a problem does not occur at the time of transfer.

 Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a schematic side view showing a configuration of an example of a transfer type hologram obtained in the present invention.

This transfer type hologram includes a base material 1, a hologram film 2 provided on the base material 1 so as to be peelable, and a release layer 3 between the hologram film 2 and the hologram film.

As the substrate 1, a material having a strength enough to support the hologram film 2, a property that facilitates the transfer operation of the hologram film, and a transparency described later can be suitably used.

As the substrate 1, any material can be used as long as it satisfies such characteristics.
It is convenient that the hologram film 2 having an appropriate flexibility can easily peel the hologram film 2 in the transfer operation.

The optical properties required for the substrate 1 are optical properties that do not affect the operation of image exposure, that is, such transparency that the exposure operation can be favorably performed at the wavelength or wavelength range of light used for exposure, If a material having such transparency (hereinafter referred to as a transparent substrate) is used, a hologram-forming photosensitive layer is laminated on a substrate having such characteristics so that it can be transferred at least after exposure and development processing. In this state, the image is exposed and developed to form a hologram on the substrate, and the obtained laminate can be used as it is as a transfer hologram, which is convenient in terms of production efficiency.

As the substrate used for such purposes, glass, or, for example, polyethylene, polypropylene,
Poly (4-methyl) pentene, polyvinyl chloride, polyvinylidene chloride, polyacrylonitrile, polyesters such as polyethylene terephthalate, and crystalline polymers such as polyamides are mainly used. What was made transparent by stretching in the biaxial direction to generate oriented crystals; polymethyl methacrylate, polycarbonate, polyacrylate, polyether ether ketone, polysulfone, styrene-methyl methacrylate copolymer, acrylic acid polyhydric alcohol ester ( CR-39)
And a transparent substrate composed mainly of an amorphous polymer.

The thickness of the base material 1 may be appropriately selected depending on the material of the base material used within a range satisfying the above characteristics. For example, when the base material 1 is used as a transparent base material made of a resin, for example, the mechanical strength and Normally 20μm ~ 100μ for transparency
Those having a size of about m are preferably used.

Further, the transfer performance of the hologram film 2 is enhanced on the surface of the base material 1 on the hologram film 2 side, if necessary.
Alternatively, in order to improve the suitability with a release layer as described later, for example, a physical treatment such as a discharge treatment using corona or plasma, a flame treatment, or the like; a chemical treatment using sulfuric acid, nitric acid, a fluoride compound, an alkali, a silane compound, or the like. A surface treatment such as a chemical treatment may be applied.

However, since the above-mentioned transparent substrate is used as the substrate 1, it is desirable that these surface treatments and the like be performed within a range where the above-mentioned optical characteristics required for the transparent substrate are not impaired.

As the hologram film 2, various volume phase holograms in the form of a film on which a desired image is recorded can be used.

Above all, a volume phase hologram using a vinyl carbazole polymer as a sensitizer satisfies the performance requirements for the sensitizer mentioned above, and has excellent moisture resistance and storage stability of the obtained hologram itself, and The vinylcarbazole-based polymer is used as a hologram-forming sensitizer in the present invention because it is excellent in stability against various operations during hologram formation or transfer.

The vinyl carbazole polymer refers to polyvinyl carbazole, an alkyl-substituted product of polyvinyl carbazole, a halogen-substituted derivative of polyvinyl carbazole, and a polymer mainly composed of these, and one or more of these may be used as desired. Specifically, for example, polyvinyl carbazole, 3-chlorovinyl carbazole polymer,
A 3-bromovinylcarbazole polymer, a 3-iodovinylcarbazole polymer, a 3-methylvinylcarbazole polymer, a 3-ethylvinylcarbazole polymer, a chlorinated polyvinylcarbazole, a brominated polyvinylcarbazole, or the like can be used. Above all, unsubstituted polyvinyl carbazole is easy to obtain, and the obtained holograms are particularly excellent in performance, so that they are practically suitable.

The vinyl carbazole-based polymer may be copolymerized with another monomer, if necessary, for controlling properties such as strength and flexibility when formed into a film. Other monomers that can be used in such applications include, for example, in addition to the above-mentioned vinyl carbazoles, vinyl esters such as vinyl acetate, esters of acrylic acid and methacrylic acid, and styrene and styrene derivatives copolymerized by radical polymerization. And vinyl monomers which can be used. For such purposes, for example, other polymers such as polystyrene, styrene-butadiene copolymer, and styrene-hydrogenated butadiene copolymer can be blended and used as long as a hologram image can be recorded.

These are used by selecting the ratio of addition so that desired characteristics can be obtained. This vinyl carbazole-based polymer is used for holography in a state activated by radiation with an iodine compound.

As the iodine compound, for example, carbon tetraiodide, iodoform, ethylene tetraiodide, triiodoethane, tetraiodoethane, pentaiodoethane, coexist in a polymer component such as hexaiodoethane, sufficient for visible light wavelength Those which can constitute a sensitive layer having sensitivity are used.

The sensitizer layer using the vinyl carbazole polymer having such a structure shows sensitivity to visible light up to 560 nm,
After exposing the interference pattern by a coherent laser of two light beams of the object light and the reference light having an appropriate wavelength in such a wavelength region, further swelling by a solvent, a high resolution by a method of undergoing a development process using a shrinkage phenomenon, A volume phase hologram with high diffraction efficiency can be formed.

In order to provide the hologram film 2 on the base material 1, the transparent base material described above is used as the base material 1, and the photosensitive layer for hologram formation can be peeled off the transparent base material via a release layer. A method in which the layers are stacked as described above and subjected to predetermined exposure and development processing can be used.

The transfer type hologram having such a configuration is obtained by superposing the exposed surface of the hologram film 2 on the surface of the material to be transferred onto which the hologram film 2 is to be transferred, and pressing them together.
The hologram film 2 can be transferred onto another desired material to be transferred.

That is, “peelable” in the present invention means that the hologram film 2 can be peeled from the substrate 1 without any change in its shape or image recording state during the above-described transfer operation. .

In the present invention, a good transfer operation can be realized by providing the release layer 3 between the base material 1 and the hologram film 2.

The release layer 3 used for such a purpose may be formed of a material and a layer thickness having a function of facilitating the separation between the substrate 1 and the hologram film 2 during the transfer operation.

Since the release layer 3 used for such a purpose is developed together with the hologram-forming sensitizer layer, a layer having resistance to a developing solution (organic solvent) is used. (When a vinyl carbazole polymer is used, 30 to 35 dyne / c
m) having a surface tension large enough or small enough to obtain a good exfoliation state, for example, a layer made of a polymer or a low molecular surface modification called a silane coupling agent or a titanium coupling agent. A layer made of a filler can be used.

Specific examples of the material that can constitute the release layer 3 include polymers such as polyvinyl alcohol, polyvinyl pyrrolidone, polyfluoroethylene-propylene, and polyorganosiloxane; silanes such as γ-glycidoxypropyltrimethoxysilane and vinyltrimethoxysilane. Coupling agents; titanium coupling agents such as isopropyl tristearoyl titanate and isopropyl trioctyl titanate;

Further, since the release layer in the present invention does not have a specific absorption band in the wavelength region of 400 to 800 nm, even when this release layer is left on the hologram after the transfer operation, the distinctive coloration indicated by the hologram is clear. Can be shown.

The release layer may be made of a material having a function as a protective layer of the hologram film, or various additives capable of imparting a protective function to the release layer may be added to give the release layer 3 a function as a protective layer. If so, a protective layer can be automatically provided on the hologram film after transfer.

Examples of the release layer forming material that can also function as a protective layer include polyethylene terephthalate, polyetheretherketone, polyperfluoroethylene-propylene, polyvinylidene fluoride, polyvinyl alcohol, and the like.

Further, as an additive that can be added to impart a function as a protective layer, for example, as an ultraviolet absorber, 2
Examples thereof include triazole derivatives such as-(hydroxyphenyl) benzotriazole, triazine derivatives such as 1,3,5-tris (2'hydroxyphenyl) triazine, and benzophenone derivatives such as resole seal monobenzoate.

When a transparent substrate is used as the substrate 1 for the purpose described above, and the release layer 3 is present at the time of exposure for forming a hologram, the release layer 3 is also made of the same transparent material as the substrate 1. Is required.

The release layer 3 can be provided by laminating a layer made of, for example, the above-mentioned polymer on the substrate 1 or treating the surface of the substrate 1 with a solution containing a silane coupling agent or a titanium coupling agent.

On the other hand, on the exposed surface of the hologram film 2, in order to improve the transfer operation, or to improve the fixation of the hologram film after transfer on the material to be transferred,
As shown in FIG. 2, an adhesive or sticky layer 4 may be provided.

As a material that can be used for the layer 4, a good adhesive or tacky effect can be obtained, and further, an adhesive utilizing the layer,
A material that does not adversely affect the hologram film 2 in the adhesion step and that does not itself react chemically and physically with the hologram film 2 to harm the hologram film 2 according to the desired configuration of the transfer hologram. Select and use.

For example, an acrylic ester-based polymer, a vinyl acetate-based polymer, an α-cyanoacrylate, a urethane-based adhesive, a rubber-based adhesive, an epoxy-based adhesive, and the like that satisfy the above characteristics are selected and used. For example, when using a polyester, by appropriately changing the copolymer composition of acrylate, butyl acrylate, 2-ethylhexyl acrylate and ethylene,
Since the characteristics are adjusted according to the target object so as to obtain a desired effect, the characteristics can be selected and used.

Note that the layer 4 may be pretreated with a primer as necessary.

As the form of the adhesive or the pressure-sensitive adhesive, if the effect of using the same can be obtained, for example, one-pack type, two-pack type, aqueous latex, oily latex, hot melt type (powder type, sheet type), heat seal Any form, such as a type for use, may be used.

In order to provide the layer 4, depending on its form, a method of directly applying the film onto the hologram film 2 (or the hologram-forming photosensitive agent layer), or bonding a film formed once by casting or the like to the hologram film 2 is used. Alternatively, a method of sticking may be appropriately selected and used.

When the layer 4 is provided as an adhesive layer, for example, 10
An adhesive layer that can be adhered under the conditions of 0 to 120 ° C. and several kg / cm ² can be suitably used.

Further, the adhesion and adhesive strength of the layer 4 is, for example, 200 g / 2
About 5 mm or more is enough.

Further, when a transparent base material is used as the base material 1 as described above, and the layer 4 is provided on the hologram-forming recording material before the exposure treatment, the layer 4 is also transparent. Transparency similar to that of the base material is required, but this is not limited as long as the layer 4 is provided on the hologram film formed after the exposure and development processing.

The transfer hologram obtained in the present invention may have a metal or metal oxide layer 5 provided on the exposed surface of the hologram film 2 as shown in FIG.

The layer 5 can constitute a back of an image observed on the hologram film 2 when the hologram film 2 is transferred to the material to be transferred, and its material, color and shape, layer thickness, and the position where the hologram film 2 is provided are appropriately determined. By making the selection, the holographic image can be made sharper and more attractive.

In particular, when the color of the material to be transferred impairs the image observed on the hologram film, by providing this layer as an opaque layer, good image observation is always possible.

The layer 5 used for such purpose is, for example, InO, Al ₂ O ₃ ,
One or more of Al, An, and the like can be laminated on a predetermined portion of the upper surface of the hologram film 2 by a method such as a vapor deposition method with a layer thickness of about 50 ° to 5000 °.

〔Example〕

 Hereinafter, the present invention will be described in more detail with reference to examples.

Example 1 On a 50 μm polyethylene terephthalate film as a substrate, a polymerization degree of 1200 (a saponification degree of 86
%) Of polyvinyl alcohol to a thickness of 5 μm. The transmittance of the laminate obtained in this manner was measured using a spectrophotometer UV.
FIG. 4A shows the results measured by IDEC-650.

Next, a solution prepared by dissolving 2.5 g of poly (N-vinylcarbazole) and 0.2 g of carbon tetraiodide in 30 g of monochlorobenzene was placed on a spinner (Mikasa Spinner, 1H-) in the dark.
It was applied using 2) and dried to obtain a hologram-forming photosensitive layer having a layer thickness of 7 μm.

When the absorbance of the obtained sensitizer layer was measured with a spectrophotometer UVIDEC-650 (manufactured by JASCO Corporation), it had an absorption edge up to 560 nm.

An Ar laser (514.5 nm) was used for the sensitizer layer, and the light intensity ratio was 1: 1 (the sum of the light intensities of both beams was 15 mJ / cm ² immediately before the incidence).
The image corresponding to the desired object was recorded according to the Denisshuk method under the following conditions.

After the exposure, the sensitizer layer is sequentially processed in the following steps to obtain a transfer hologram provided with a Lippmann-type reflection hologram having a desired image recorded on the substrate so as to be transferable on the substrate. Was.

Immersion in toluene at 20 ° C. for 2 minutes Immersion in xylene for 30 ° C. for 3 minutes Drying after immersion in n-heptane at 25 ° C. for 3 minutes
It has a spatial frequency of 000 lines / mm and a diffraction efficiency of 88%.
It was a volume phase hologram having a transmittance of 90%.

The transfer-type hologram obtained in this manner is superimposed on a transfer material obtained by applying Polysol AB-412BN (manufactured by Showa Polymer Co., Ltd.) to Kent paper via the hologram film surface, and a pressure of about 2 kg / cm ² is applied. The hologram film could be transferred onto Kent paper by applying the roller with a roller.

The characteristics of the transferred hologram were the same as those immediately after the formation, and a good holographic image could be observed there.

Example 2 First, a glass substrate was washed, and then the glass substrate was put into a closed container filled with a trimethylchlorosilane gas, and a release layer was formed by a reaction between the glass substrate surface and the gas.

Next, 2.5 g of poly (N-vinylcarbazole) and carbon tetraiodide were placed on a glass substrate on which the above-mentioned release layer was formed in a dark place.
A solution in which 2 g was dissolved in 30 g of monochlorobenzene was applied using a spinner (Mikasa Spinner, 1H-2) and dried to obtain a hologram-forming photosensitive layer having a layer thickness of 7 μm.

When the absorbance of the obtained sensitizer layer was measured with a spectrophotometer UVIDEC-650 (manufactured by JASCO Corporation), it had an absorption edge up to 560 nm.

An Ar laser (514.5 nm) was used for the sensitizer layer, and the light intensity ratio was 1: 1 (the sum of the light intensities of both beams was 15 mJ / cm ² immediately before the incidence).
The image corresponding to the desired object was recorded according to the Denisshuk method under the following conditions.

After exposure, the sensitizer layer was sequentially processed in the following steps to obtain a transfer hologram provided so as to be transferable on a Lippmann type reflection hologram base material on which a desired image was recorded on the base material. .

Immersion in toluene at 20 ° C. for 2 minutes Immersion in xylene for 30 ° C. for 3 minutes Drying after immersion in n-heptane at 25 ° C. for 3 minutes
It has a spatial frequency of 000 lines / mm and a diffraction efficiency of 88%.
It was a volume phase hologram having a transmittance of 90%.

The indium tin oxide (IT) was applied to the vinyl carbazole film surface of the transfer type hologram film thus obtained.
O) was sputtered to form a film having a surface resistance of 200 Ω / cm ² . FIG. 4B shows the absorption spectrum. next,
This was immersed in water and peeled off to obtain a hologram film having an ITO film on the surface.

The hologram film thus obtained is superimposed on a transfer material obtained by applying Polysol AB-412BN (manufactured by Showa Polymer Co., Ltd.) to Kent paper via the hologram film surface, and a pressure of about 2 kg / cm ² is applied. The hologram film could be transferred onto Kent paper by applying a roller.

The characteristics of the transferred hologram were the same as those immediately after the formation, and a good holographic image could be observed there.

〔The invention's effect〕

The transfer type hologram obtained in the present invention has a configuration in which a hologram film is provided on a transparent base material via a release layer so that the hologram film can be separated from the base material. With a simple operation of transferring to various objects, a desired holographic image can be easily and easily applied to desired portions of various objects. Also, for example, a hologram film can be transferred onto a suitable mount, and enjoyed as a picture or a photograph.

In the above-described type using the uneven surface, when holograms are directly laminated on various objects by pressure bonding or bonding, the influence of deformation or breakage on the unevenness formed on the surface is inevitable, but the present invention is not limited to this. Transfer type holograms
Since a volume type phase hologram film is used, such a problem does not occur during transfer.

Furthermore, since the release layer does not have a specific absorption band in the wavelength region of 400 to 800 nm, even when the release layer is left on the hologram after the transfer operation, it clearly shows the unique coloration indicated by the hologram. Can be.

[Brief description of the drawings]

1 to 3 are schematic side views each showing a typical configuration example of a transfer type hologram obtained by the present invention, and FIG. 4 is a diagram showing a substrate provided with a release layer or absorption of a hologram in an embodiment of the present invention. It is a figure showing a spectrum. 1: base material 2: hologram film 3: release layer 4: adhesive or tacky layer 5: layer composed of metal and / or metal oxide A: absorption spectrum of the laminate in Example 1 B: hologram in Example 2 Absorption spectrum

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Tetsuro Kuwayama 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (56) References JP-A-61-292181 (JP, A)

Claims (1)

(57) [Claims] 1. A method for producing a transfer type hologram, wherein a hologram-forming photosensitive layer provided on a transparent base material in a peelable manner is subjected to hologram exposure and development processing with an organic solvent to form a reflection type volume phase hologram. Between the substrate and the hologram-forming sensitizer layer, has solvent resistance to the organic solvent used in the development process, and 40
A method for producing a transfer type hologram, wherein a release layer having no specific absorption band is provided in a wavelength range of 0 to 800 nm, and the hologram-forming sensitizer layer contains a vinylcarbazole-based polymer.