JPH08297455A - Hologram recording material, hologram recording medium and production of hologram using that - Google Patents

Abstract

PURPOSE: To provide a hologram recording material for a volume phase type hologram showing weather resistance, heat resistance, storage stability, high resolution by a dry process, high diffraction efficiency, high transparency, and reproducibility for regenerated wavelength, and to provide a hologram recording medium and a production method of a hologram using this material. CONSTITUTION: The hologram recording material contains an aromatic thermosetting resin, aliphatic monomers which enable radical polymn. and a photopolymn. initiator which activates radical polymn. and cation polymn. when exposed to chemical active radiation. The aromatic thermosetting resin is soluble in a solvent and the resin has at least one ethylene oxide ring which enables cation polymn. in the structural unit and has 900-6000mol.wt. and 400-6700 epoxy equiv. Further, a thermosetting resin which is soluble with a solvent and has at least one ethylene oxide ring in the structural unit and 340-500 mol.wt. and 180-220 epoxy equiv. is added to the material.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention is highly sensitive to visible light, particularly argon laser light, or electron beams, and is excellent in weather resistance, heat resistance and storage stability, and has high resolution.
The present invention relates to a hologram recording material and a hologram recording medium used for forming a volume phase hologram having excellent hologram characteristic values such as diffraction efficiency and transparency, and a hologram manufacturing method using the same.

[0002]

2. Description of the Related Art Conventionally, since holograms can reproduce three-dimensional stereoscopic images, they have been used for books, covers for magazines, displays for POPs, gifts, etc. because of their excellent design and decorative effects. . Since holograms can be said to be equivalent to the recording of information in submicron units, they are also used for counterfeit prevention marks such as securities and credit cards.

Particularly, the volume phase hologram modulates the phase without absorbing the light beam passing through the image by forming spatial interference fringes having different refractive indexes in the hologram recording medium, not by optical absorption. Therefore, in recent years, in addition to display applications, application to a hologram optical element (hereinafter, referred to as HOE) represented by a head-up display (HUD) mounted on a vehicle is expected.

By the way, the volume phase hologram recording material constituting the volume phase hologram is required to be highly sensitive to a laser beam having a visible oscillation wavelength and exhibit a high resolution. Further, when actually used for forming a hologram, it is required that characteristics such as diffraction efficiency of hologram, wavelength reproducibility of reproduced light, band width (half-value width of reproduced light peak) and the like are suitable for the purpose. Especially, the hologram recording material for HOE has a diffraction efficiency of 500 spatial frequency.
90% or more at 0 to 6000 lines / mm, half-value width (bandwidth) of reproduction light peak is 20 to 30 nm, peak wavelength of reproduction wavelength is preferably within 5 nm from photographing wavelength, and further stored for a long time There is also a need for good stability.

Conventionally, as a recording material for such a volume phase hologram, a bleached silver salt and a dichromated gelatin type photosensitive material have been generally used. This dichromated gelatin type photosensitive material is the most widely used material for recording a volume phase hologram because of its high diffraction efficiency and low noise characteristics. However, since this photosensitive material has a short shelf life, it has to be prepared every time a hologram is prepared and wet development is performed, so that the hologram is deformed during the swelling and shrinking process of gelatin required for hologram preparation. Therefore, there is also a problem that the reproducibility of the hologram is poor. Further, the silver salt sensitive material requires complicated processing after recording, and is not a photosensitive material which is satisfactory from the viewpoint of stability and workability. Furthermore, all of these above-mentioned light-sensitive materials have a problem that they are inferior in environmental resistance characteristics such as moisture resistance and weather resistance.

On the other hand, a hologram recording material using poly-N-vinylcarbazole is a material having excellent environmental resistance and having the characteristics that a hologram recording material should have such as high resolution and high diffraction efficiency. Can be mentioned. For example, a hologram recording material comprising a cyclic cis-α-dicarbonyl compound as a crosslinking agent and a sensitizer (JP-A-60-45).
No. 283), 1,4,5,6,7,7-hexachloro-5-nobornene-anhydrous-2,3-dicarboxylic acid and a hologram recording material comprising a dye (JP-A-60-2272).
No. 80), a hologram recording material composed of 2,3-bornanedione and thioflavin (JP-A-60-26008).
No. 0), a hologram recording material comprising thioflavin T and iodoform (JP-A-62-123489).
Etc. have been proposed. However, the above-mentioned hologram recording material has a problem in that it requires wet development, requires complicated processing steps, and is poor in reproducibility. Also, since it is a photosensitive material containing poly-N-vinylcarbazole as a main component, it has excellent chemical stability, high resolution, and environmental resistance, but since poly-N-vinylcarbazole is easily crystallized and whitened, transparency is reproduced. There is a problem that the property is poor and the usable solvent is limited. Furthermore, further improvement in sensitivity characteristics is desired.

Further, as a hologram recording material which can be photocured with high sensitivity, a photocurable resin composition comprising a combination of 3-ketocoumarins and a diaryl iodonium salt, which are constituent components of a photopolymerization initiator, (Japanese Patent Laid-Open No. 60- 88005), and a hologram recording material in which a photopolymerization initiator is combined with polymethylmethacrylate as a supporting polymer (JP-A-4-31590), which are chemically stable, And it has high resolution and high sensitivity, but because the voids are formed by wet processing, the dispersion of the peak wavelength of the reproduction wavelength and the expansion of the half-value width of the peak wavelength, and the supported polymer is slightly dissolved in the swelling solvent during development. However, there is a problem that uneven development is likely to occur, and since there are many voids in the hologram, heat resistance and heat pressure resistance are poor. It has a problem in that.

On the other hand, a photopolymerizable photosensitive material capable of producing a hologram in one processing step without wet processing is disclosed in US Pat. No. 3,993,485 and US Pat. No. 3,658,526. . The former has two types of light-sensitive materials, and as a first example, a combination of two polymerizable unsaturated ethylenic monomers having different reactivity and refractive index and a photopolymerization initiator, such as cyclohexyl methacrylate, N-. A photosensitive resin composition composed of vinylcarbazole and benzoin methyl ether, which can be hologram-recorded by sandwiching it between two glass plates and exposing with a two-beam optical system. Also,
As a second example, a polymerizable unsaturated ethylenic monomer having a similar refractive index, an unsaturated ethylenic monomer acting as a cross-linking agent when it is polymerized, and a refractive index different from those of the two monomers are used. A photosensitive resin composed of four components of a non-reactive compound and a polymerization initiator, such as butyl methacrylate, ethylene glycol dimethacrylate, 1-phenylnaphthalene and benzoin methyl ether, and capable of producing a hologram in the same manner as in the first example. It is a composition. No matter which photosensitive resin composition is used, the polymerization of the more reactive monomer proceeds at the portion where the light intensity of the interference fringes formed by the two light fluxes becomes strong, and a monomer concentration gradient occurs, resulting in a highly reactive monomer. Is diffused into a portion having a high light intensity, and a monomer or non-reactive compound having a low reactivity is diffused into a portion having a low light intensity. In this way, interference fringes are recorded with a difference in refractive index, and a volume phase hologram is formed.

However, the above-mentioned photosensitive resin composition for hologram recording also has the following problems. That is, in the case shown in the first example, polymerization of a monomer having low reactivity also occurs to some extent, and high refractive index modulation cannot be obtained. In the second example, the non-reactive compound 1
-Even after the hologram is completed, phenylnaphthalene is still present in the system as a low molecular weight compound, and thus has no storage stability. Further, in any of the examples, since the mixture has a low molecular weight and the viscosity is low, there are many problems in workability and reproducibility such as difficulty in sandwiching between substrates and formation of a thick film.

The latter US Pat. No. 3,658,526 discloses a method for producing a stable hologram composed of a hologram recording material in which a photopolymerizable ethylenic monomer and a photopolymerization initiator are mixed in a polymer matrix. A single exposure to working radiation results in a permanent volume phase hologram, which is subsequently fixed by blanket irradiation with actinic radiation. The hologram recording material disclosed herein is intended to provide many advantages in terms of workability and reproducibility, but its diffraction efficiency is low. In this hologram recording material, the refractive index modulation of the completed hologram is 0.00
It is in the range of 1 to 0.003. As a result, the reproduced image of the formed hologram has a limited brightness. Although it is possible to give some brightness by thickening the hologram recording layer, this solution results in the manufacturer using a large amount of hologram recording material, and at the same time, in some media such as in-vehicle devices. It causes a problem when it is used by fixing it in laminated glass such as head up display. It should also be noted that holograms formed thereby generally have a reduced diffraction efficiency due to long-term storage.

As an improved technique including the method for producing the hologram recording material disclosed in US Pat. No. 3,658,526, US Pat. No. 4,942,112 and US Pat. No. 5,098,803 are disclosed. These have a basic composition of a thermoplastic resin, a polymerizable unsaturated ethylenic monomer, and a photopolymerization initiator, and either a thermoplastic resin or a polymerizable unsaturated ethylenic monomer is added to improve the refractive index modulation. We are trying to make a difference in refractive index by using a compound having an aromatic ring. However, like the one disclosed in US Pat. No. 3,658,526, since a high molecular weight resin is used as a binder matrix, the diffusibility of the monomer during exposure is limited, and a large amount of exposure is required. In addition, high diffraction efficiency cannot be obtained. Further, in order to improve this point, a non-reactive plasticizer is added, but this use causes a problem in the film strength of the formed hologram, and the non-reactive plasticizer causes the hologram to disappear. Even after completion, it remains in the system as a low molecular weight compound and has no storage stability. In addition to this, since the carrier that holds this is a thermoplastic resin, it has the drawback of being inferior in heat resistance.

On the other hand, according to Japanese Unexamined Patent Publication (Kokai) No. 5-107999, which is a technique for improving the above-mentioned drawbacks, a cation-polymerizable monomer and a cation-polymerization initiator are blended in place of the plasticizer in the above patent to form a hologram. Although the problem due to the residual of the non-reactive plasticizer is solved later, it requires a considerable light irradiation for fixing after the hologram formation, and the low-molecular weight cationically polymerizable monomer diffuses during fixing. In addition, the formed hologram is distorted, and high diffraction efficiency cannot be obtained. Further, as in the prior art, since the carrier holding the same is a thermoplastic resin, it has the drawback of being inferior in heat resistance. Furthermore, in a system that does not use a thermoplastic resin as a carrier for holding,
There are many problems in workability and reproducibility such as difficulty in sandwiching between substrates and formation of thick film due to low viscosity.

Further, a photosensitive resin composition for hologram recording comprising an epoxy resin, a radically polymerizable unsaturated ethylenic monomer and a photoradical polymerization agent is disclosed in JP-A-5-94.
014. As far as the examples are seen, two kinds of epoxy resins are used, but when an ultraviolet curable epoxy resin is used, a complicated work such as performing radical polymerization and cationic polymerization with lights of different wavelength ranges is required. At the same time, in order to adjust the diffusibility of the monomer, fine adjustment such as increasing the viscosity by pre-exposure is required, which makes workability and reproducibility difficult. Further, when a thermosetting epoxy resin and a curing agent are used, the workability is very poor because the curing of the epoxy resin for fixing requires a considerable amount of UV curing and heating time. In addition, high diffraction efficiency cannot be obtained with the improved technique disclosed herein.

[0014]

As described above, a photopolymerizable photosensitive material capable of producing a hologram in a single processing step without wet processing is a polymerizable material of monomers for obtaining refractive index modulation or It has a problem of dispersibility, and also has a problem of storage stability due to addition of a carrier carrying a monomer and a non-reactive additive, and further, workability of hologram production,
There is a demand for a hologram recording material and a hologram recording medium having excellent hologram characteristics such as diffraction efficiency, transparency and reproducibility of the obtained hologram.
The need is increasing in OE. Therefore, the present invention is, for example, a volume phase hologram that is excellent in weather resistance, heat resistance, chemical stability, storage stability, and has high resolution by dry processing, high diffraction efficiency, high transparency, and reproduction wavelength reproducibility. It is an object of the present invention to provide a hologram recording material and a hologram recording medium capable of forming a film, and a hologram manufacturing method using the same.

[0015]

The present invention has been made to solve the above problems, and the invention according to claim 1 has at least one solvent-soluble, cationically polymerizable ethylene oxide ring in a structural unit. The molecular weight is 900 to 6
000 and epoxy equivalent of 400 to 670
A solvent for a hologram recording material having an aromatic thermosetting resin in the range of 0, a radically polymerizable aliphatic monomer, and a photoinitiator system that activates radical polymerization and cationic polymerization when exposed to actinic radiation. Soluble, having at least one ethylene oxide ring in the structural unit,
A hologram recording material, characterized in that a thermosetting resin having a molecular weight in the range of 340 to 500 and an epoxy equivalent in the range of 180 to 220 is added.

A second aspect of the present invention is the hologram recording material according to the first aspect, wherein the solvent-soluble, cationically polymerizable ethylene oxide ring has at least one ethylene oxide ring in the structural unit, and the molecular weight is in the range of 900 to 6000. Epoxy equivalent is solvent-soluble in 100 parts by weight of an aromatic thermosetting resin having a range of 400 to 6700 and 20 to 80 parts by weight of a radical-polymerizable aliphatic monomer.
0.5 to 10 parts by weight of a thermosetting resin having at least one ethylene oxide ring in a structural unit and having a molecular weight of 340 to 500 and an epoxy equivalent of 180 to 220 is added. Characterize.

The invention described in claim 3 is the hologram recording material according to claim 1, wherein the photoinitiator system comprises a diaryl iodonium salt and a sensitizing dye.

According to a fourth aspect of the invention, in the hologram recording material according to the third aspect, the sensitizing dye is an organic dye compound selected from cyanine or merocyanine dyes, coumarin dyes and chalcone dyes. Characterize.

The present invention as defined in claim 5 is any one of claims 1 to 4.
A hologram recording medium comprising a hologram recording layer made of the hologram recording material described in 1 above and an oxygen barrier film.

According to a sixth aspect of the present invention, the hologram interference pattern is recorded on the hologram recording medium of the fifth aspect by hologram exposure, and then the entire surface of the ultraviolet ray is exposed and heated to fix the hologram interference pattern. And a method for producing a hologram.

[0021]

In the hologram recording material, hologram recording medium and hologram manufacturing method of the present invention, the radically polymerizable aliphatic monomer (B) has at least one solvent-soluble, cationically polymerizable ethylene oxide ring in its structural unit. And a molecular weight of at least one substituent selected from unsubstituted phenyl, substituted phenyl, chlorine and bromine is in the range of 900 to 6000 and an epoxy equivalent is 4
It is evenly distributed in the aromatic thermosetting resin (A) in the range of 00 to 6700. However, by irradiating this recording material with laser interference light, it is possible to obtain a strong light interference effect in the laser irradiation area. As the monomer (B) is polymerized and polymerized, the monomer (B) moves from its periphery, and at this time, it is solvent-soluble and has at least one ethylene oxide ring in the structural unit, and has a molecular weight of 340 to 5
A thermosetting resin (D) having an epoxy equivalent of 180 to 220 in the range of 00 is also dispersed in this system, and exhibits a function of a plasticizer to promote the transfer of the monomer (B). As a result, the monomer concentration is high in a portion of the laser-irradiated portion having a strong optical interference action, and is low in a portion of the laser-irradiated portion having a weak optical interference action. As a result, a difference in refractive index occurs between the two parts, and it is estimated that the latent image of the hologram is recorded. Further, the remaining monomer (B) is fixed by polymerization by the whole surface ultraviolet light exposure treatment and heat treatment after the hologram exposure, and the aromatic thermosetting resin (A) and thermosetting resin (D) which are the supports are also fixed. Becomes a cross-linked structure due to the cationic polymerization, and the weather resistance is improved. In addition, since the thermosetting resin (D) that functions as a plasticizer does not easily scatter even after long-term storage,
Storage stability of hologram recording material is also thermosetting resin (D)
It is improved compared to the system in which is not added.

Further, the hologram recording material of the present invention is superior to the conventional hologram recording material in the reproducibility of the peak wavelength of reproduction light and its bandwidth, and is also excellent in environment resistance. Can be applied to.

[0023]

The present invention will be described in detail below. FIG. 1 is a schematic diagram illustrating the configuration of a hologram photosensitive recording medium made of the hologram photosensitive recording material of the present invention, and FIG. 2 is a schematic explanatory diagram illustrating a two-beam optical system for hologram photographing.

The component (A) constituting the hologram recording material of the present invention has at least one solvent-soluble, cationically polymerizable ethylene oxide ring in the structural unit, or further, unsubstituted phenyl, substituted phenyl, chlorine or bromine. An aromatic thermosetting resin having at least one substituent selected from, for example, bisphenol A, bisphenol AD, bisphenol B, bisphenol AF, bisphenol S, brominated bisphenol A, novolac, o-cresol novolak, p. -Epoxy compounds represented by the following chemical formulas, which are produced by the condensation reaction of various phenol compounds such as alkylphenol novolacs and epichlorohydrin. However, it is not limited to these.

[0025]

Embedded image (In the formula, n = 1 to 20.)

[0026]

Embedded image (In the formula, R represents an alkyl group, and n = 1 to 20.)

Particularly, the aromatic thermosetting resin has a molecular weight of 9
The range of 00 to 6000 is preferable, and when the molecular weight is smaller than this range, the film forming property is deteriorated and uniform coating is difficult, and when the molecular weight is larger than this range, synthesis is generally difficult. Further, this aromatic thermosetting resin preferably has an epoxy equivalent of 400 to 6700, and there is a problem that good cationic polymerization does not proceed outside this range.

The radical-polymerizable aliphatic monomer as the component (B) has at least one ethylenic unsaturated bond in its structural unit, and it is a polyfunctional monomer other than a monofunctional vinyl monomer. It contains a vinyl monomer, and may be a mixture thereof. Specifically, (meth) acrylic acid, itaconic acid, maleic acid,
(Meth) acrylamide, diacetone acrylamide,
High-boiling-point vinyl monomers such as 2-hydroxyethyl (meth) acrylate, and aliphatic polyhydroxy compounds such as ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, dipropylene glycol,
Tripropylene glycol, tetrapropylene glycol, neopentyl glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,10-decanediol, trimethylolpropane And di- or poly (meth) acrylic acid esters such as pentaerythritol, dipentaerythritol, sorbitol, and mannitol. However, it is not limited to these.

Chemical Action of Component (C) of the Present Invention As a photoinitiator system which activates radical polymerization and cationic polymerization when exposed to radiation, diaryl iodonium salts and the like are preferable, and sensitized with an organic dye compound by a sensitizing dye. It is also possible to do so. Examples of the diaryliodonium salt used in the present invention include Macromolecules, 10 , 1
307 (1977). And compounds such as diphenyliodonium, ditolyliodonium, phenyl (p-anisyl) iodonium, and bis (p-te).
Examples thereof include chlorides, bromides, borofluoride salts, hexafluorophosphate salts, and hexafluoroarsenate salts of iodonium such as rt-butylphenyl) iodonium and bis (p-chlorophenyl) iodonium. Any material may be used as long as it satisfies the requirements.

Further, as the sensitizing dye used together with the diaryliodonium salt in the above description, organic dye compounds such as cyanine or merocyanine derivatives, coumarin derivatives and chalcone derivatives can be used. A specific example will be described below.

Examples of cyanine or merocyanine derivatives are fluorescein, rhodamine, 2'7'-dichlorofluorescein, 3,3'-dicarboxyethyl-2,
2'-thiocyanine bromide, anhydro-3,3 '
-Dicarboxymethyl-2,2'-thiocyanine betaine, 1-carboxymethyl-1'-carboxyethyl-2,2 'quinocyanine bromide, anhydro-3,
3'-dicarboxyethyl-5,5 ', 9-trimethyl-2,2'-thiacarbocyanine betaine, 3,3'
-Dihydroxyethyl-5,5 'dimethyl-9-ethyl-2,2'-thiacarbocyanine bromide, anhydro-3,3'-dicarboxymethyl-2,2'-thiacarbocyanine betaine, 2- [3- Ethyl-4-oxo-5- (1-ethyl-4-quinolinidene) -ethylidene-2-thiazolinidene-methyl] -3-ethylbenzoxazolium bromide, 3-ethyl-5- [2- (3
-Ethyl-2-benzothiazoylidene) -ethylidene]
Rhodanine, 3-ethyl-5- [2- (3-methyl-2
(3H) -thiazolinylidene) -ethylidene] -2-thio-2,4-oxazalidione, 3-ethyl-5- (3
-Ethyl-benzothiazolilidene) Rhodanine, 2-
(P-Dimethylaminostyryl) -3-ethyl, benzothiazolium iodide, 2- (p-diethylaminostyryl) -1-ethyl pyridinium iodide, 1,
The use of 3'-diethyl-2,2'-quinothiacyanine iodide and the like is preferable, but not limited thereto.

Examples of coumarin derivatives include 3- (2 '
-Benzimidazole) 7-N, N-diethylaminocoumarin, 3,3'-carbonylbis (7-diethylaminocoumarin), 3,3'-carbonylbiscoumarin,
3,3'-carbonylbis (7-methoxycoumarin),
3,3′-carbonylbis (5,7-dimethoxycoumarin), 3,3′-carbonylbis (6-methoxycoumarin), 3,3′-carbonylbis (7-acetoxycoumarin), 3,3′-carbonyl Bis (5,7-di-is
o-propoxycoumarin), 3,3′-carbonylbis (5,7-di-n-propoxycoumarin), 3,3′-
Carbonylbis (5,7-di-n-butoxycoumarin), 3,3′-carbonylbis (7-dimethylaminocoumarin), 7-diethylamino-5 ′, 7′dimethoxy-3,3′-carbonylbiscoumarin, 3-benzoylcoumarin, 3-benzoyl-5,7-dimethoxycoumarin, 3-benzoyl-6-methoxycoumarin, 3-benzoyl-7-methoxycoumarin, 3-benzoyl-8
-Methoxycoumarin, 3-benzoyl-8-ethoxycoumarin, 3-benzoyl-6-bromocoumarin, 3-benzoyl-7-dimethylaminocoumarin, 3-benzoyl-7-diethylaminocoumarin, 3-benzoyl-7
-Hydroxycoumarin, 3-acetyl-7-diethylaminocoumarin, 3-acetyl-7-methoxycoumarin,
3-acetyl-5,7-dimethoxycoumarin, 7-dimethylamino-3- (4-iodobenzoyl) coumarin,
Examples thereof include 7-diethylamino-3- (4-iodobenzoyl) coumarin and 7-diethylamino-3- (4-diethylaminobenzoyl) coumarin, but are not limited thereto.

Examples of chalcone derivatives include, but are not limited to, the compounds represented by the following chemical formulas.

[0034]

Embedded image

The solvent-soluble, thermosetting resin of component (C) of the present invention having at least one ethylene oxide ring in the structural unit, having a molecular weight in the range of 340 to 500 and an epoxy equivalent in the range of 180 to 220. Has a function as a plasticizer and a viscosity adjuster, but since it is cured by heat treatment after the hologram is produced, it exhibits characteristics such as not affecting the weather resistance of the hologram. Specific examples thereof include a liquid epoxy compound represented by the following chemical formula, which is produced by a condensation reaction of various phenol compounds such as bisphenol A, bisphenol AD, bisphenol B, bisphenol AF, bisphenol S, and brominated bisphenol A with epichlorohydrin. Is mentioned. However, it is not limited to these.

[0036]

[Chemical 4] (In the formula, n = 0 to 1)

The hologram recording material of the present invention having the above-mentioned constitution is obtained by mixing 20 to 80 parts by weight of the aliphatic monomer (B) with 100 parts by weight of the aromatic thermosetting resin (A). Is. Particularly preferred is a proportion of 40 to 70 parts by weight. If the amount is less than 20 parts by weight, the amount of monomers polymerized by holographic exposure with a laser is insufficient, so that high refractive index modulation cannot be obtained even after the heat treatment and a bright hologram cannot be obtained. Further, when the amount exceeds 100 parts by weight, the amount of the monomer becomes excessive,
Polymerization does not occur in the first holographic exposure and the amount of monomer remaining in the system increases, and as a result, the amount of monomer that remains while diffusing in the heat treatment in the manufacturing process causes polymerization, which causes interference of holograms once formed. The stripes are disturbed, high refractive index modulation cannot be obtained, and a bright hologram cannot be obtained. The amount of the photoinitiator system (C) is 0.1 to 20 parts by weight, preferably 1 to 10 parts by weight, based on 100 parts by weight of the aromatic thermosetting resin (A). Further, the amount of the sensitizing dye is 0.1 to 1 with respect to 100 parts by weight of the aromatic thermosetting resin (A).
It is 0 part by weight, preferably 0.5 to 5 parts by weight. Further, the thermosetting resin (D) is 0.5 to 10 parts by weight with respect to 100 parts by weight of the aromatic thermosetting resin (A),
It can preferably range from 1 to 7.5. Since the amount used is limited by the optical density of the photosensitive layer to be formed and the film thickness thereof, it is preferable to use it within the range where the optical density does not exceed 2 (or, in the case of the transmittance, the irradiation light for hologram recording). The transmittance is preferably 1% or more). If it deviates from this range, it becomes difficult to obtain a high diffraction efficiency and the sensitivity characteristic deteriorates.

As described above, the respective components are appropriately selected, and the photosensitive liquid obtained by mixing them at an arbitrary ratio is subjected to a glass plate or a polycarbonate by using a known coating means such as a spin coater, a roll coater or a bar coater. A hologram recording medium 1 for ordinary hologram imaging in which a hologram shown in FIG. 1 is produced by coating a substrate 2, such as a plate, a polymethylmethacrylate plate, or a polyester film, in a film form.
Is. Further, a protective layer 4 may be provided as an oxygen blocking film on the hologram layer 3. The protective layer 4 is made of, for example, a material equivalent to that of the above-mentioned substrate, or a plastic such as polyolefin, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol or polyethylene terephthalate, and an optically transparent material such as glass, to sandwich the hologram layer. It is formed by laminating, stacking with an extruder, coating a solution, or the like. When applying the photosensitive solution, it may be diluted with an appropriate solvent if necessary, but in that case, it is necessary to dry after applying it on the substrate, and as described above, irradiation during photographing is performed. It is desirable that the light transmittance is adjusted to 1% or more.

Further, the hologram recording material of the present invention comprises
If desired, various additives such as known binders, plasticizers, thermal polymerization inhibitors, chain transfer agents, and antioxidants may be added.

The process of holographically exposing the hologram recording medium 1 using the above hologram recording material to form a latent image is shown in the schematic view of the two-beam optical system for transmission hologram imaging shown in FIG. According to this, the laser light 6 emitted from the laser 5 is applied to the hologram photosensitive recording medium 1 via the mirror 7, the beam splitter 8, the spatial filter 9, and the lens 10. It should be noted that in the present invention, the fixing process is performed by a dry process after the hologram is photographed by exposure. Although not described in detail and shown in the drawings, the present invention can be similarly applied to the production of a reflection hologram, and a reflection hologram having excellent hologram characteristics can be obtained.

When a hologram image is recorded on the hologram photosensitive recording medium 1, a laser irradiation is applied in accordance with a desired image so that a portion of the laser irradiation portion having a strong optical interference action is an aromatic thermosetting resin. Radical-polymerizable aliphatic monomer (B) uniformly dispersed in (A)
However, when exposed to laser (laser interference light) irradiation, the photopolymerization initiator acts to polymerize and polymerize, so that the radically polymerizable aliphatic monomer (B) around it is moved. Further, the thermosetting resin (D) is also dispersed in this system, exhibits the function of a plasticizer, and promotes the movement of the monomer (B). Therefore, in the laser-irradiated portion where the optical interference is strong, Since the concentration of the radical-polymerizable aliphatic monomer (B) is high and the concentration of the radical-polymerizable aliphatic monomer (B) is low at the site where the light interference action is weak, the light of the hologram photosensitive recording medium 1 is reduced. Refractive index modulation occurs due to the difference in refractive index due to the difference in density between the part with strong interference and the part with weak optical interference,
Thereby, hologram image recording is performed.
Further, the remaining monomer (B) is fixed by polymerization by the whole surface ultraviolet light exposure treatment and heat treatment after the hologram exposure, and the aromatic thermosetting resin (A) and thermosetting resin (D) which are the supports are also fixed. Has a cross-linked structure due to cationic polymerization, so that the weather resistance, heat resistance, and chemical stability of the hologram recording medium 1 are improved. Further, since the thermosetting resin (D) added as a plasticizer is similarly cured, the plasticizer does not scatter due to long-term storage and the hologram characteristics such as diffraction efficiency and peak wavelength do not change with time. The storage stability of the medium is also improved.

In the exposure process of the interference pattern,
As a light source suitable for the hologram recording material of the present invention, a helium-cadmium laser, an argon laser, a krypton laser, a helium neon laser, or the like can be used, but the light source is not limited thereto.

Hereinafter, the present invention will be described in more detail with reference to specific examples. <Example 1-4> 100 parts by weight of bisphenol epoxy oligomer Epicoat 1007 (epoxy equivalent: 2900, manufactured by Yuka Shell Epoxy Co., Ltd.), 50 parts by weight of triethylene glycol diacrylate (TEGDA), and diphenyliodonium hexafluorophosphate 5
Parts by weight, 1 part by weight of 3,3′-carbonylbis (7-diethylamino) coumarin to 100 parts by weight of 2-butanone, 5 parts by weight of bisphenol epoxy resin Epicoat 807 (epoxy equivalent: 172, manufactured by Yuka Shell Epoxy Co., Ltd.) A hologram recording material was prepared by mixing and dissolving it to prepare a photosensitive solution.
This photosensitive solution was applied onto a glass plate so as to have a film thickness of about 20 μm to form a hologram layer, and then the hologram layer was covered with a polyvinyl alcohol (PVA) film to prepare a hologram recording medium. The hologram recording material triethylene glycol diacrylate (TEGDA)
The holographic recording media were prepared by changing the content of each as shown in Table 1.

The hologram recording medium was exposed using an argon laser (514.5 nm) as a light source by the two-beam optical system for hologram recording shown in FIG. 2 to prepare a hologram, and then the entire surface was irradiated with a high pressure mercury lamp. 1
Heat treatment was performed at 00 ° C. for 30 minutes to fix the hologram.

The diffraction efficiency of the obtained hologram was measured by a spectrophotometer manufactured by JASCO Corporation. In this spectrophotometer, a photomultimeter having a slit with a width of 3 mm can be installed on the circumference of a sample with a radius of 20 cm. As the measurement conditions, monochromatic light having a width of 0.3 mm was incident on the sample at an angle of 45 degrees, and diffracted light from the sample was detected. The diffraction efficiency was defined as the ratio between the largest value other than the specularly reflected light and the value obtained when the incident light was directly received without placing the sample.
The diffraction efficiency before heating was also measured in the same manner. Table 1 shows the evaluation results.

[0046]

[Table 1]

<Example 5-8> The hologram recording medium prepared in Example 1-4 was stored in the dark at 40 ° C for 30 days, and a hologram was prepared and fixed in the same manner as in Example 1-4. The diffraction efficiency was measured. Table 2 shows the evaluation results.

[0048]

[Table 2]

<Examples 9 to 13> 1,6-hexanediol diacrylate (HDO) was used in place of the triethylene glycol diacrylate (TEGDA) of Example 1 above.
DA), diethylene glycol diacrylate (DEG
DA), neopentyl glycol diacrylate (NP
GDA), trimethylolpropane triacrylate (TMPTA), and pentaerythritol triacrylate (PETA) were used, and a hologram was prepared and fixed in the same manner as in Example 1, and the diffraction efficiency was measured. The evaluation results are shown in Table 3.

[0050]

[Table 3]

HDODA; 1,6-hexanediol diacrylate DEGDA; diethylene glycol diacrylate NPGDA; neopentyl glycol diacrylate TMPTA; trimethylolpropane triacrylate PETA; pentaerythritol triacrylate

<Examples 14-18> Examples 9-13 above
The hologram recording medium prepared in 1. was stored in the dark at 40 ° C. for 30 days, a hologram was prepared and fixed in the same manner as in Example 9-13, and the diffraction efficiency was measured. The evaluation results are shown in Table 4.

[0053]

[Table 4]

<Examples 19-24> Examples 1, 9-13
Bisphenol epoxy resin Epicoat 1007
Instead of (epoxy equivalent 2700, manufactured by Yuka Shell Epoxy Co., Ltd.), brominated epoxy resin (Araldite XAC8
101; Epoxy equivalent :? ? ? , Manufactured by Japan Ciba-Geigy Co., Ltd.), and holograms were prepared and fixed in the same manner as in Examples 1 and 9-13, and the diffraction efficiency thereof was measured. The evaluation results are shown in Table 5.

[0055]

[Table 5]

<Example 25-30> Example 19-2 above
The holographic recording medium prepared in 4 was stored in the dark at 40 ° C for 30
The hologram was stored for a day, a hologram was prepared and fixed in the same manner as in Examples 19-24, and the diffraction efficiency thereof was measured. The evaluation results are shown in Table 6.

[0057]

[Table 6]

<Examples 31-36> Examples 1, 9-13
In place of 3,3′-carbonylbis (7-diethylamino) coumarin which is a sensitizing dye of 2-benzoyl-3-
A hologram was prepared and fixed in the same manner as in Examples 1 and 9-13 except that (p-dimethylaminophenyl) -2-propenenitrile was used, and the diffraction efficiency was measured. The evaluation results are shown in Table 7. However, instead of the wavelength of 514.5 nm of the argon laser, the wavelength of 488 nm
I used the light of.

[0059]

[Table 7]

<Examples 37-42> Example 31-3 above
The holographic recording medium prepared in 6 was stored in the dark at 40 ° C. for 30 minutes.
After being stored for a day, a hologram was prepared and fixed in the same manner as in Examples 31-36, and the diffraction efficiency thereof was measured. The evaluation results are shown in Table 8.

[0061]

[Table 8]

<Examples 43-48> Examples 1, 9-13
In place of 3,3′-carbonylbis (7-diethylamino) coumarin, which is the sensitizing dye of 3-ethyl-5- [2
-(3-Ethyl-2-benzothiazolilidene) ethylidene] rhodanine, respectively, except that each of Examples 1 and 9 was used.
A hologram was prepared and fixed in the same manner as in -13, and the diffraction efficiency was measured. The evaluation results are shown in Table 9. However, light having a wavelength of 488 nm was used instead of the wavelength of 514.5 nm of the argon laser.

[0063]

[Table 9]

<Examples 49-54> Example 43-4 above
The holographic recording medium prepared in 8 was stored in the dark at 40 ° C. for 30 minutes.
It was stored for a day, a hologram was prepared and fixed in the same manner as in Examples 43 to 48, and the diffraction efficiency was measured. The evaluation results are shown in Table 10.

[0065]

[Table 10]

Comparative Example The same operation as in Example 1-4 was conducted except that the bisphenol epoxy resin Epicoat 807 (epoxy equivalent: 172, manufactured by Yuka Shell Epoxy Co., Ltd.) in Example 1-4 was not added, and the diffraction thereof was performed. The efficiency was measured. The evaluation results are shown in Table 11.

[0067]

[Table 11]

The holograms according to the invention shown in Examples 1-54 were produced at 25 ° C., 60% RH for 180 days and 150 ° C.
Even when left for 10 hours in the environment, no decrease in diffraction efficiency was observed.

[0069]

INDUSTRIAL APPLICABILITY As described above, the present invention has at least one solvent-soluble, cationically polymerizable ethylene oxide ring in the structural unit as described above, or further, unsubstituted phenyl, substituted phenyl, chlorine, bromine. Having a molecular weight of at least one substituent selected from
000 and epoxy equivalent of 400 to 670
It contains an aromatic thermosetting resin in the range of 0, a radically polymerizable aliphatic monomer, and a photoinitiator that activates radical polymerization and cationic polymerization when exposed to actinic radiation, and is soluble in a solvent and has an ethylene oxide ring. A hologram recording material having at least one in a structural unit, a thermosetting resin having a molecular weight in the range of 340 to 500 and an epoxy equivalent in the range of 180 to 220, and having high storage stability, Moreover, the aromatic thermosetting resin that serves as a support and the thermosetting resin that functions as a plasticizer and a viscosity modifier have a crosslinked structure due to cationic polymerization due to the heat treatment after hologram production, and the weather resistance is improved.

As described above, in the dry process, in particular, in the hologram manufacturing method in which the hologram recording material and the hologram recording medium are fixed by the whole surface exposure process of ultraviolet rays after the hologram exposure and the heating process, the sensitivity, the resolution and the A hologram recording material and a hologram recording medium for HOE having excellent diffraction efficiency, transparency, heat resistance, weather resistance, chemical stability and storage stability, and extremely high performance, and further It is possible to provide a hologram manufacturing method using.

[Brief description of drawings]

FIG. 1 is a schematic diagram illustrating the configuration of a hologram recording medium made of the hologram recording material of the present invention.

FIG. 2 is a schematic diagram illustrating a two-beam optical system for hologram recording.

[Explanation of symbols]

 1 Hologram Recording Medium 2 Substrate 3 Photosensitive Layer 4 Protective Layer 5 Laser 6 Laser Light 7 Mirror 8 Beam Splitter 9 Spatial Filter 10 Lens 11 Lens

Claims (6)

[Claims] 1. A solvent-soluble, cationically polymerizable ethylene oxide ring having at least one ethylene oxide ring in the structural unit,
An aromatic thermosetting resin having a molecular weight of 900 to 6000 and an epoxy equivalent of 400 to 6700; and (B) a radical-polymerizable aliphatic monomer.
(C) In a hologram recording material having a photoinitiator system that activates radical polymerization and cationic polymerization when exposed to actinic radiation, (D) is solvent-soluble, has at least one ethylene oxide ring in a structural unit, and has a molecular weight of Three
A hologram recording material comprising a thermosetting resin in the range of 40 to 500 and an epoxy equivalent of 180 to 220. 2. (A) Aromatic thermosetting having a solvent-soluble, cationically polymerizable ethylene oxide ring in a structural unit and having a molecular weight of 900 to 6000 and an epoxy equivalent of 400 to 6700. With respect to 100 parts by weight of the organic resin and 20 to 80 parts by weight of the radically polymerizable aliphatic monomer (B), (D) solvent-soluble, having at least one ethylene oxide ring in the structural unit, and having a molecular weight of 340 to 500 2. The hologram recording material according to claim 1, wherein 0.5 to 10 parts by weight of a thermosetting resin having an epoxy equivalent of 180 to 220 is added in the range. 3. The hologram recording material according to claim 1, wherein the photoinitiator system comprises a diaryl iodonium salt and a sensitizing dye. 4. The hologram recording material according to claim 3, wherein the sensitizing dye is an organic dye compound selected from cyanine or merocyanine dyes, coumarin dyes, and chalcone dyes. 5. A hologram recording medium comprising a hologram recording layer made of the hologram recording material according to claim 1 and an oxygen barrier film. 6. A hologram manufacturing method characterized in that the hologram interference pattern is recorded on the hologram recording medium according to claim 5 by hologram exposure, and then the hologram interference pattern is fixed by performing an ultraviolet whole surface exposure process and a heating process. Method.