JPH0916058A - Multilayered hologram recording body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the peeling of a hologram layer from a glass substrate by interposing an adhesive layer between the hologram recording layer consisting of a photopolymer and the glass substrate. SOLUTION: The adhesive layer 3 is applied on the glass substrate 1 and the hologram recording layer 2 is applied thereon. Further, a cover film 4 consisting of PET, etc., is laminated thereon, by which the multilayered hologram recording body is constituted. The monomers of the photopolymer of the part where the light in the hologram recording layer 2 is cast are polymerized and the change in the refractive index is induced when the hologram is exposed. The unpolymerized monomers in the hologram recording layer 2 are polymerized and the double bonds of the monomers in the adhesive layer 3 are polymerized with the double bonds remaining in the hologram recording layer 2, by which the adhesive force of the hologram recording layer 2 and the adhesive layer 3 is increased when the entire part is irradiated with UV rays. The adhesive power of the glass substrate l and the adhesive layer 3 is increased by heating the hologram recording body.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multilayer hologram recording body, and more particularly to a multilayer hologram recording body having a hologram recording layer made of a photopolymer coated on a glass substrate via an adhesive layer.

[0002]

2. Description of the Related Art Conventionally, various hologram optical elements (HOE) using a volume phase hologram such as a hologram color filter (Japanese Patent Application No. 5-12170) have a hologram recording layer made of a photopolymer on a glass substrate. A fringe pattern of a hologram is recorded by exposure on a multi-layer hologram recording body provided with a cover film made of a PET film or the like for blocking oxygen that inhibits polymerization of the photopolymer at the time of recording It is created by post-treatment of irradiation and heat treatment.

[0003]

However, such a hologram recording layer has a problem that it is easily peeled off from the substrate because of its poor adhesion to the glass substrate after the post-treatment and the handling is inconvenient. If the cover film has birefringence or has a difference in refractive index from the hologram recording layer, it is necessary to remove the cover film after recording and post-treatment. The adhesiveness between the hologram recording layer and the cover film is higher than the adhesiveness, and there is a problem that the hologram recording layer is peeled off from the glass substrate or scratched.

The present invention has been made in view of the above problems of the prior art, and an object thereof is to provide a hologram recording layer with an adhesive layer interposed between the hologram recording layer of photopolymer and the glass substrate. It is an object of the present invention to provide a hologram recording body that does not separate from a glass substrate.

[0005]

A multi-layer hologram recording body of the present invention which achieves the above object is characterized in that an adhesive layer is interposed between a hologram recording layer made of a photopolymer and a glass substrate. Is.

In this case, it is desirable that a cover film is laminated on the surface of the hologram recording layer in a peelable manner.

Further, it is desirable that the adhesive layer is made of an adhesive whose adhesion between the hologram recording layer and the glass substrate is enhanced by irradiation with ionizing radiation and heating which are post-treatments after hologram recording on the photopolymer. .

The adhesive layer preferably comprises a binder polymer having a hydroxyl group, a carboxyl group, a mercapto group, an alkoxysilyl group or an ester group, a polymerizable monomer and an ionizing radiation initiator.

Further, it is desirable that the adhesive layer has a refractive index difference with the hologram recording layer of 0.1 or less and almost no birefringence.

[0010]

In the present invention, since the adhesive layer is interposed between the hologram recording layer made of a photopolymer and the glass substrate, the hologram recording layer is hard to be peeled off from the glass substrate and is easy to handle, and the hologram recording layer Even when it is necessary to remove the cover film laminated on the surface, the hologram recording layer is not separated from the glass substrate by the cover film and is not scratched.

[0011]

EXAMPLES The basic principle of the multilayer hologram recording material of the present invention is that the hologram recording layer is formed between the hologram recording layer made of a photopolymer and the glass substrate by irradiation of ultraviolet rays and heating which is a post-treatment after the recording of the photopolymer. And interposing an adhesive layer that causes adhesion between the glass substrate and
This is to make it difficult for the hologram recording layer to peel off from the glass substrate when the cover film is removed after the post-treatment.

This principle will be described with reference to the schematic diagram of FIG. FIG. 1A shows the layer structure of the multilayer hologram recording body according to the present invention. That is, an adhesive layer 3 composed of a binder polymer having a hydroxyl group, a carboxyl group, a mercapto group, an alkoxysilyl group, or an ester group, a polymerizable monomer, and an ultraviolet initiator is applied on a glass substrate 1, and this adhesion is performed. A hologram recording layer 2 of a photopolymer composed of a binder polymer, a polymerizable monomer, an initiator and a dye is applied on the agent layer 3, and a cover film 4 such as PET (polyethylene terephthalate) is coated on the hologram recording layer 2. It is stacked.

In this state, when hologram exposure is performed as shown in FIG. 1B, the monomer of the photopolymer in the portion of the hologram recording layer 2 exposed to light is polymerized to cause refractive index modulation. Then, as shown in FIG. 3C, when the whole is irradiated with ultraviolet rays, the unpolymerized monomer in the hologram recording layer 2 is polymerized and the double bond of the monomer in the adhesive layer 3 is changed to the hologram recording layer 2. The adhesive force between the hologram recording layer 2 and the adhesive layer 3 is increased by polymerizing with the double bond remaining therein and by the anchor effect due to the unevenness of the interface between the hologram recording layer 2 and the adhesive layer 3.

Next, as shown in FIG. 3D, when the hologram recording body is heated, polymerization of the unpolymerized portion remaining in the hologram recording layer 2 proceeds to amplify the refractive index modulation, and at the same time, the adhesive layer. A hydroxyl group, a carboxyl group, a mercapto group, an alkoxysilyl group or an ester group in the binder polymer of 3, and an oxygen atom, a sulfur atom or a silicon atom,
By covalently bonding a silicon atom on the surface of the glass substrate 1 or an oxygen atom in a hydroxyl group bonded to the silicon atom, the hydroxyl group, the carboxyl group and the mercapto group in the binder polymer of the adhesive layer 3 and the surface of the glass substrate 1 are also formed. The hydrogen bond with the hydroxyl group bonded to the silicon atom increases the adhesive force between the glass substrate 1 and the adhesive layer 3.

Therefore, the adhesiveness between the hologram recording layer 2 and the glass substrate 1 becomes strong, and even if the cover film 4 is peeled off as shown in FIG. 6 (e), the hologram recording layer 2 is accompanied by the glass substrate. It does not come off from 1.

As a specific example, an adhesive layer having the following composition is applied in a thickness of 20 μm on a quartz glass substrate having a thickness of 10 mm, and a photopolymer layer having the following composition is formed thereon.
It is applied in a thickness of μm, and P of 50 μm in thickness is further applied.
An ET film was laminated to obtain a multilayer hologram recording body of the present invention. Laser light having a wavelength of 514 nm was applied to the hologram recording body from the PET film side at a light intensity of 30 mJ / cm ^2.
Then, the hologram was exposed to light and the interference fringes of the hologram were recorded.

Next, from the PET film side, 365 nm
Was irradiated with ultraviolet light having a light intensity of 100 mJ / cm ² . Then, heat treatment was performed at a temperature of 120 ° C. for 20 minutes.

Thereafter, the PET film was peeled off in order to avoid birefringence, but the photopolymer layer was not peeled off from the glass substrate and was not scratched. Further, the interference fringes of the hologram were not disturbed.

[Composition of Photopolymer Layer and Adhesive Layer] Photopolymer Layer Polyvinyl acetate (binder) 66.9 w% Acrylic monomer 29.0 w% 3,3 ′, 4,4′-tetra (t-butylperoxy) Carbonyl) benzophenone (initiator) 4.0w% 3,3'-carbonylbis (7-diethylcoumarin) (dye) 0.1w% Adhesive layer Polyvinyl acetate-polyvinyl alcohol copolymer (binder) 67.0w % Acrylic monomer 29.0 w% benzoisobutyl ether (ultraviolet initiator) 4.0 w% As described above, the adhesive layer 3 includes a binder having a hydroxyl group, a carboxyl group, a mercapto group, an alkoxysilyl group or an ester group. As long as it consists of a polymer, a polymerizable monomer, and an ultraviolet or electron beam initiator, various selections can be made. It is possible to select, but it is desirable to select a material having a small difference in refractive index from the hologram recording layer 2, preferably 0.1 or less, and having no birefringence.

Although the multilayer hologram recording material of the present invention has been described above based on the embodiments, the present invention is not limited to these embodiments and various modifications can be made.

[0021]

As is apparent from the above description, according to the multilayer hologram recording body of the present invention, since the adhesive layer is interposed between the hologram recording layer made of a photopolymer and the glass substrate, the hologram recording is performed. The layer is difficult to peel off from the glass substrate, easy to handle, even when it is necessary to remove the cover film laminated on the surface of the hologram recording layer, the hologram recording layer is not peeled from the glass substrate along with the cover film, Does not hurt.

[Brief description of the drawings]

FIG. 1 is a schematic diagram for explaining the basic principle of a multilayer hologram recording body of the present invention.

[Explanation of symbols]

 1 ... Glass substrate 2 ... Hologram recording layer 3 ... Adhesive layer 4 ... Cover film

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location B32B 27/16 B32B 27/16 C08F 2/46 MDJ C08F 2/46 MDJ C09J 4/00 JBG C09J 4 / 00 JBG 201/02 JAU 201/02 JAU G02B 5/32 G02B 5/32

Claims (5)

[Claims] 1. A multilayer hologram recording body comprising an adhesive layer interposed between a hologram recording layer made of a photopolymer and a glass substrate. 2. The multilayer hologram recording body according to claim 1, wherein a cover film is laminated on the surface of the hologram recording layer so as to be peelable. 3. The adhesive layer is made of an adhesive that increases the adhesive force between the hologram recording layer and the glass substrate by irradiation with ionizing radiation and heating, which is a post-treatment after hologram recording on the photopolymer. The multilayer hologram recording body according to claim 1 or 2, characterized in that. 4. The adhesive layer comprises a binder polymer having a hydroxyl group, a carboxyl group, a mercapto group, an alkoxysilyl group or an ester group, a polymerizable monomer and an ionizing radiation initiator. 4. The multilayer hologram recording body according to any one of items 1 to 3. 5. The adhesive layer has a difference in refractive index from the hologram recording layer of 0.1 or less and has almost no birefringence, and the adhesive layer has almost no birefringence. The multilayer hologram recording body described.