JPH09106242A - Holographic recording photosensitive resin composition, hologram recording medium, and method for producing hologram using this hologram recording medium - Google Patents

Abstract

(57) Abstract: Provided are a photosensitive resin composition for hologram recording, a hologram recording medium having high sensitivity to visible light, excellent storage stability, and good hologram characteristic values, and a method for producing a hologram. thing. SOLUTION: This photosensitive resin composition for hologram recording comprises a solvent-soluble, cationically polymerizable thermosetting epoxy oligomer, a liquid at room temperature and atmospheric pressure, and a boiling point of 1 at atmospheric pressure.
An aliphatic monomer having at least one radically polymerizable ethylenic unsaturated bond at a temperature of 00 ° C. or higher, a radical species that activates radical polymerization when exposed to actinic radiation, and Bronsted that activates cationic polymerization. An aromatic onium salt which generates an acid or a Lewis acid, a cationic dye sensitizer capable of sensitizing the aromatic onium salt in the visible light region, and an ammonium borate salt represented by the general formula (I) as main components. It is characterized by Embedded image

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photosensitive resin composition for hologram recording used for forming a volume phase hologram, a hologram recording medium, and a method for producing a hologram using this hologram recording medium. light,
Especially for hologram recording with high sensitivity to argon laser, krypton laser, helium-neon laser, and semiconductor laser, excellent weather resistance and storage stability, and good hologram characteristic values such as resolution, diffraction efficiency, and transparency. The present invention relates to a photosensitive resin composition, a hologram recording medium, and a hologram manufacturing method using the hologram recording medium.

[0002]

2. Description of the Related Art A volume phase hologram modulates a phase without absorbing a light beam passing through an image by forming spatial interference fringes having different refractive indexes in a hologram recording medium instead of optical absorption. can do. The volume phase hologram is preferred for its excellent design and is used for covers of books, magazines, POP displays, gifts and the like. In addition, since holograms are equivalent to recording information on the order of submicrons, they are also used to prevent counterfeiting of securities and credit cards. Further, in recent years, in addition to display applications, application to a hologram optical element (HOE) represented by a head-up display mounted on an automobile is expected. A photosensitive resin composition for hologram recording and a hologram recording medium used for producing a hologram are required to be highly sensitive to a laser beam having a visible oscillation wavelength and exhibit high resolution. In actual use, it is required that the hologram diffraction efficiency, reproduction light wavelength reproducibility, bandwidth (half-value width of reproduction light peak), and other characteristics are suitable for the purpose. Specifically, in order to make a recording material for HOE, the diffraction efficiency is set to a spatial frequency of 5000 to 6
90% or more at 000 lines / mm, half-value width (bandwidth) of reproduction light peak is 20 to 30 nm, reproduction wavelength peak wavelength is preferably within 5 nm from the photographing wavelength, and further storage stability for a long time You also need to be excellent.

The general principle of hologram production is described in several documents and technical books such as "Holographic Display" (Junpei Tsujiuchi; Industrial Books), Chapter 2. According to these, a two-beam coherent optical system, that is, one of the laser beams is generally irradiated on a recording object, and a photosensitive recording medium, for example, a photographic dry plate, is placed at a position where the total reflected light from the recording object can be received. Get burned. In addition to the reflected light from the object, the recording medium is directly irradiated with the other coherent light without hitting the object. The reflected light from the object is called the object light, and the light directly radiated on the medium is called the reference light, and the interference fringes between the reference light and the object light are recorded as image information. Then, when the treated recording medium is exposed to light and observed at the proper eye position, the light from the illumination source will cause the reflected light wavefront to first reach the recording medium from the object during recording. As a result, the hologram is diffracted so that the object image similar to the real image of the object is three-dimensionally observed. A hologram formed by making reference light and target light incident on a recording medium from the same direction is known as a transmission hologram. On the other hand, holograms formed by making light incident from opposite sides of a recording medium are generally known as reflection holograms. Transmissive holograms include, for example, US Pat. No. 3,506,327 and US Pat. No. 3,894.
It can be obtained by a known method such as that disclosed in Japanese Patent No. 787. In addition, the reflection hologram is
For example, it can be produced by the known method disclosed in US Pat. No. 3,532,406.

Refractive index modulation is a value for comparing the hologram characteristics of holograms formed as images. This is because when a diffraction grating is produced by directly irradiating the recording medium with the same angle formed by the two light fluxes and the medium, the ratio of the incident light diffracted by the diffraction grating, that is, the diffraction efficiency and the recording medium It is a value specified by the thickness. Refractive index modulation is a quantitative measure of the change in refractive index that occurs in exposed and unexposed areas of a volume hologram, that is, in areas where light interferes to strengthen and weaken, and is based on H. Kogelnik's. Theoretical formula [Bell. Syst. Tec
h. J. , 48 , 2909, (1969). ] It can be obtained by. Generally, a reflection hologram has a larger number of interference fringes formed per 1 mm than a transmission hologram, so that recording is difficult and it is difficult to obtain a high refractive index modulation.

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, this light-sensitive material has a short shelf life and must be prepared each time it is manufactured. In addition, since the wet development is performed, the hologram is deformed in the process of swelling and contracting gelatin which is necessary for producing the hologram. Therefore, there is also a problem that the hologram reproducibility is poor. Also, the silver salt sensitive material is
It is not a photosensitive material that requires complicated processing after recording and 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, it has excellent environmental resistance and
A hologram recording material using poly-N-vinylcarbazole can be cited as a material having characteristics that a hologram recording material should have, such as high resolution and high diffraction efficiency. For example, a hologram recording material comprising a cyclic cis-α-dicarbonyl compound as a crosslinking agent and a sensitizer (JP-A-60-45).
283), 1,4,5,6,7,7-hexachloro-5-norbornene-anhydrous-2,3-dicarboxylic acid, and a hologram recording material comprising a dye (JP-A-60-227).
280), a hologram recording material composed of 2,3-bornanedione and thioflavin (JP-A-60-2600).
No. 80), a hologram recording material composed of thioflavin T and iodoform (Japanese Patent Laid-Open No. 62-123489), and the like. However, since these hologram recording materials also require wet development, they require complicated processing steps and are inferior in reproducibility. Further, they are photosensitive materials containing poly-N-vinylcarbazole as a main ingredient. Therefore, although it is chemically stable, has high resolution, and is excellent in environmental resistance, poly-N-vinylcarbazole is easily crystallized and whitens easily, reproducibility of transparency is poor, and the solvent is limited. It has the problem of being lost. In addition, further improvement in sensitivity characteristics is desired.

Further, as a recording material which can be photocured with high sensitivity, a photocurable resin composition used in combination with 3-ketocoumarins and a diaryl iodonium salt, which are constituent components of a photopolymerization initiator, is disclosed in JP-A-60-88005. Further, there is proposed a hologram recording material (JP-A-4-31590) in which the photopolymerization initiator is combined with polymethylmethacrylate as a supporting polymer. However, even though these recording materials are chemically stable and have high resolution and high sensitivity, since the voids are formed by a wet process, the variation of the peak wavelength of the reproduction wavelength and the expansion of the half width of the peak wavelength are widened. In addition, during development, there is a problem that uneven development is likely to occur because the supported polymer is slightly dissolved in the swelling solvent, and moreover, there are many voids in the hologram, resulting in poor heat resistance and heat and pressure resistance. Have a point.

In order to solve such problems, 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. It is disclosed. The former includes 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 and N-vinyl. A photosensitive resin composition composed of carbazole and benzoin methyl ether, which can be hologram-recorded by sandwiching it between two glass plates and exposing it with a two-beam optical system. 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. Which is 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 a hologram can be prepared in the same manner as in the first example. Resin composition. Whichever photosensitive resin composition is used, the polymerization of the monomer having higher reactivity proceeds in the portion where the light intensity of the interference fringes formed by the two-beam optical system is increased, and the concentration gradient of the monomer is generated, resulting in A high monomer diffuses into a portion with high light intensity, and a monomer with low reactivity or a non-reactive compound diffuses into a portion with low light intensity. In this way, interference fringes are recorded with a difference in refractive index, and a volume phase hologram is formed.

However, such a hologram recording photosensitive resin composition 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-phenylnaphthalene is present in the system as a low molecular weight compound even after the hologram is completed, and therefore 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.

On the other hand, the latter US Pat. No. 3,658,526 discloses a method for producing a stable hologram comprising a hologram recording material containing a photopolymerizable ethylenic monomer and a photopolymerization initiator in a polymer matrix. A single exposure to actinic radiation results in a permanent volume phase hologram. The formed hologram is fixed by subsequent blanket irradiation of 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.
It is in the range of 001 to 0.003. As a result, the reproduced image of the formed hologram has a limited brightness.
It is possible to give some brightness by making the hologram recording layer thick, but this solution is
This causes manufacturers to use a large amount of hologram recording material, and causes a hindrance when fixed and used in a certain medium, for example, a laminated glass such as a vehicle head-up display. It should also be noted that holograms formed thereby generally have a reduced diffraction efficiency due to long-term storage.

Therefore, an improved technique including the method for producing the hologram recording material disclosed in US Pat. No. 3,658,526 is disclosed in US Pat. No. 4,942,112, US Pat. No. 5,098,803, and JP-A-2-308.
It is disclosed in Japanese Patent Application Laid-Open No. 1-30832 and Japanese Patent Application Laid-Open No. 2-3082. 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 the monomers and the like is a thermoplastic resin, it has the drawback of being inferior in heat resistance.

Further, in order to improve this drawback, Japanese Patent Laid-Open Publication No. Hei 5 (1998)
In Japanese Patent Laid-Open No. 107999, there is proposed a recording material in which a cationically polymerizable monomer and a cationic polymerization initiator are blended in place of the plasticizer in the above-mentioned patent to solve the problem caused by the residual non-reactive plasticizer after hologram formation. There is.

However, in this recording material, a considerable amount of light irradiation is required for fixing after hologram formation, and a distortion is generated in the hologram formed because the low molecular weight cationically polymerizable monomer diffuses during fixing. Occurs, and high diffraction efficiency cannot be obtained. Further, as in the prior art, since the carrier that holds the above-mentioned monomers and the like is a thermoplastic resin, it has the drawback of being inferior in heat resistance. Furthermore, a system that does not use a resin binder as a carrier for holding has many problems in workability and reproducibility, such as difficulty in sandwiching between substrates due to low viscosity and difficulty in forming a thick film. .

Therefore, the above-mentioned US Pat. No. 4,942,112, US Pat.
As a material improved from the recording material described in JP-A-107999, a photosensitive resin composition for hologram comprising an epoxy resin, a radically polymerizable unsaturated ethylenic monomer and a photoradical polymerization agent is disclosed in JP-A-5-94014. It is disclosed.

As far as the examples of JP-A-5-94014 are concerned, two kinds of epoxy resins are used in this hologram photosensitive resin composition.

[0016]

However, 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, and the diffusibility of the monomer is increased. To adjust
Pre-exposure requires fine adjustment such as increasing viscosity,
It still has a problem that workability and reproducibility are 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, the improved technique disclosed here has a big problem that a high diffraction efficiency cannot be obtained.

Under such a technical background, the present inventors have
A solvent-soluble thermosetting epoxy oligomer capable of cationic polymerization and a liquid at normal temperature and pressure and a boiling point of 100 at normal pressure.
An aliphatic monomer having at least one radically polymerizable ethylenically unsaturated bond having a temperature of ℃ or higher, a radical species that activates radical polymerization when exposed to actinic radiation, and a Bronsted acid that activates cationic polymerization Alternatively, a photoinitiator that generates a Lewis acid and a sensitizing dye that sensitizes the photoinitiator are contained as main components, and hologram properties such as resolution, diffraction efficiency, and transparency are good, and chemicals such as heat resistance are used. Has already proposed a hologram photosensitive recording material and the like that can obtain a volume phase hologram excellent in mechanical stability (Japanese Patent Application Nos. 6-46742 and 6-149796).
Japanese Patent Application No. 6-149797, Japanese Patent Application No. 6-14979
(See No. 8, etc.).

An object of the present invention is to further improve the photosensitivity and the like in this hologram photosensitive recording material. That is, the object of the present invention is that visible light, particularly argon laser, krypton laser, high sensitivity to helium-neon laser and semiconductor laser, further excellent weather resistance and storage stability, and resolution, diffraction. efficiency,
It is an object of the present invention to provide a photosensitive resin composition for hologram recording having a better hologram characteristic value such as transparency, a hologram recording medium, and a method for producing a hologram using this hologram recording medium.

[0019]

Therefore, the inventors of the present invention have conducted extensive studies to solve the above-mentioned problems, and as a result, sensitized with the photoinitiator in the hologram photosensitive recording material developed by the inventors. By selecting a specific material for the dye, this hologram photosensitive recording material has good sensitivity to coherent light having an oscillation source from the visible light region to the near-infrared light region (400 nm or more) (especially, the photosensitive speed). The present invention has been completed and the present invention has been completed.

That is, the photosensitive resin composition for hologram recording according to the invention of claim 1 is a solvent-soluble, cationically polymerizable thermosetting epoxy oligomer, a liquid at room temperature and atmospheric pressure, and a boiling point at atmospheric pressure. An aliphatic monomer having at least one ethylenically unsaturated bond capable of radical polymerization at 100 ° C. or higher, a radical species that activates radical polymerization and a Bronsted that activates cationic polymerization when exposed to actinic radiation. An aromatic onium salt generating an acid or a Lewis acid, and a cationic dye sensitizer capable of sensitizing the aromatic onium salt in the visible light region,
It is characterized by containing an ammonium borate salt represented by the general formula (I) as a main component.

[0021]

Embedded image (In the formula, R ₁ , R ₂ , R ₃ and R ₄ each independently represent an alkyl group, an aryl group, an alkoxyl group, an allyl group, an alkenyl group, an alkynyl group, an alicyclic group or a heterocyclic group. , R ₅ , R ₆ , R ₇ and R ₈ each independently represent an alkyl group, an aryl group, an alkoxyl group, an allyl group, an alkenyl group, an alkynyl group, an alicyclic group, a heterocyclic group or a hydrogen atom. ) And in the present invention, the thermosetting epoxy oligomer is a thermosetting epoxy oligomer represented by the general formula (II),

[0022]

Embedded image (Wherein R ₉ and R ₁₀ each represent a hydrogen atom or a functional group selected from a methyl group, an ethyl group and a trifluoromethyl group, and the degree of polymerization is n = 1 to 20) or the general formula (III ) A thermosetting epoxy oligomer represented by

[0023]

Embedded image (Wherein the degree of polymerization n = 1 to 20) or a thermosetting epoxy oligomer represented by the general formula (IV),

[0024]

Embedded image (Wherein R ₁₁ represents a hydrogen atom or a methyl group, X represents a hydrogen atom or a halogen atom, and the degree of polymerization is n = 1 to 20), or a thermosetting epoxy oligomer represented by the general formula (V),

[0025]

Embedded image (In the formula, R ₁₂ represents an alkyl group, and the degree of polymerization n = 1 to 20.
Is applicable (Claim 2), and the general formula (V
I)

[0026]

Embedded image (In the formula, the degree of polymerization n = 1 to 20), and
A thermosetting bisphenol A type epoxy oligomer having an epoxy equivalent of 400 to 6000 and a melting point of 50 ° C. or higher measured by the Durance mercury method can also be applied (Claim 3), and further, the general formula (VII)

[0027]

Embedded image (Wherein R ₁₃ and R ₁₄ each represent a functional group selected from a hydrogen atom, a methyl group, an ethyl group, and a trifluoromethyl group, and the degree of polymerization is n = 1 to 20). Application of a curable epoxy oligomer is also possible (claim 4).

Hereinafter, each component of the photosensitive resin composition according to the present invention will be described in more detail with reference to specific examples.

First, as the above-mentioned thermosetting epoxy oligomer which is soluble in a solvent and capable of cationic polymerization, bisphenol A, bisphenol AD, bisphenol AF, bisphenol B, bisphenol S, novolac, o-cresol novolac, p-alkylphenol novolac and the like are generally used. According to the methods described in several literatures and technical books on dynamic synthesis methods, for example, "Experimental Method of Polymer Synthesis" (Takayuki Otsu, Masaetsu Kinoshita; Kagaku Dojin), Chapter 12.
Examples thereof include compounds synthesized by a condensation reaction between a corresponding phenol compound and epichlorohydrin. Specific examples thereof include solvent-soluble and cationically polymerizable thermosetting epoxy oligomers represented by general formulas (II) to (VI).

Also, trade names Epicoat 1055, 1004, 1007, 1009, 1 manufactured by Yuka Shell Epoxy Co., Ltd.
010, 1100L and 1255HX30, and the product name Araldite 7097, 6 manufactured by Ciba-Geigy Japan.
084, 6097, 6099, XAC5010, XAC
5010, XAC8100, XAC8101, 8011
LA, 8024LA and 8049SP, and trade names BROC, BR-250 and EBPS-2 manufactured by Nippon Kayaku Co., Ltd.
00 and BREN-S series of BREN series, and ESF-300 manufactured by Nippon Steel Chemical Co., Ltd.
In addition, the product name D. E. FIG. R. 66
Examples thereof include, but are not limited to, those generally commercially available as represented by 4, 667, 668 and 669.

The following alicyclic epoxy compounds produced by the condensation reaction of various hydrogenated bisphenol compounds with epichlorohydrin can also be applied.

[0032]

Embedded image (In the formula, the degree of polymerization is n = 1 to 20) Further, regarding these thermosetting epoxy oligomers, two or more kinds of oligomers may be mixed and applied as necessary. The epoxy equivalent of the thermosetting epoxy oligomer represented by the general formula (VI) is 400 to 60.
It must be 00. That is, when the epoxy equivalent is less than 400, it is uneconomical because the amount of the thermosetting epoxy oligomer required to obtain a constant viscosity increases when the photosensitive solution is prepared, and it is a low molecular weight compound. As a result, the thermosetting epoxy oligomer moves to some extent during fixing, so that a bright hologram tends not to be obtained. On the other hand, thermosetting epoxy oligomers having an epoxy equivalent of more than 6000 are generally difficult to synthesize with a stable molecular weight and with good reproducibility, and the diffusibility of the monomer deteriorates, resulting in a decrease in sensitivity and a bright hologram. Can't get Moreover, there is also a problem that good cationic polymerization does not proceed outside this range.

Next, as an aliphatic monomer having at least one radically polymerizable ethylenically unsaturated bond which is liquid at normal temperature and pressure and has a boiling point of 100 ° C. or higher at normal pressure, ethylene is contained in the structural unit. It contains at least one functional unsaturated bond, contains a polyfunctional vinyl monomer in addition to a monofunctional vinyl monomer, and may be a mixture thereof. Specifically, high-boiling vinyl monomers such as (meth) acrylic acid, itaconic acid, maleic acid, (meth) acrylamide, diacetone acrylamide, and 2-hydroxyethyl (meth) acrylate, and further aliphatic polyhydroxy compounds, For example, 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,
Di- or poly (meth) acrylic acid esters such as 6-hexanediol, 1,10-decanediol, trimethylolpropane, pentaerythritol, dipentaerythritol, sorbitol and mannitol, and dimethyloltricyclodecane monoacrylate and dimethylol. Examples thereof include alicyclic monomers such as tricyclodecane diacrylate, and preferably polyethylene glycol di (meth) acrylate or polypropylene glycol di (meth) acrylate represented by the general formula (VIII) can be mentioned. 5). In addition, two or more of these may be mixed and applied as necessary.

[0034]

Embedded image (In the formula, R _{15 to} R ₁₇ are hydrogen or a methyl group, and m,
n is 0 or more, and m + n = 1 to 20) Further, radical species and cationic polymerization that activate radical polymerization when exposed to actinic radiation (electron beam, X-ray, visible light, infrared ray, etc.) Examples of the above-mentioned aromatic onium salt which generates a Bronsted acid or a Lewis acid for activating carboxylic acid include Macromolecules, 10 , 1
307 (1977), for example, diaryl iodonium salts, triaryl sulfonium salts, triaryl phosphonium salts, iron arene complexes and the like, but are not limited thereto. Specific examples of the diaryl iodonium salt include diphenyl iodonium chloride, diphenyl iodonium trifluoromethanesulfonate, diphenyl iodonium mesylate, diphenyl iodonium tosylate, diphenyl iodonium bromide, diphenyl iodonium tetrafluoroborate, diphenyl iodonium hexafluorophosphate. , Diphenyliodonium hexafluoroantimonate, diphenyliodonium hexafluoroarsenate, bis (p-tert-butylphenyl) iodonium hexafluorophosphate, bis (p-tert-butylphenyl)
Iodonium mesylate, bis (p-tert-butylphenyl) iodonium tosylate, bis (p-tert-butylphenyl) iodonium trifluoromethanesulfonate, bis (p-tert-butylphenyl) iodonium tetrafluoroborate, bis (p
-Tert-butylphenyl) iodonium chloride, bis (p-chlorophenyl) iodonium chloride, bis (p-chlorophenyl) iodonium tetrafluoroborate and the like can be mentioned.

Examples of triarylsulfonium salts are triphenylsulfonium chloride, triphenylsulfonium bromide, tri (4-methoxyphenyl) sulfonium tetrafluoroborate and tri (p-
Examples thereof include methoxyphenyl) sulfonium hexafluorophosphate and tri (4-ethoxyphenyl) sulfonium tetrafluoroborate. Examples of triarylphosphonium salts include triphenylphosphonium chloride, triphenylphosphonium bromide, tri (4-methoxyphenyl) phosphonium tetrafluoroborate, tri (p-methoxyphenyl) phosphonium hexafluorophosphonate, tri (4-ethoxyphenyl). Examples thereof include phosphonium tetrafluoroborate.

Among these aromatic onium salts, a diaryl iodonium salt is particularly preferable because it is excellent in sensitization efficiency by the cationic dye sensitizer and easily decomposes to generate a radical species and a Lewis acid or Bronsted acid. 7).

Next, as the above-mentioned cationic dye sensitizer capable of sensitizing an aromatic onium salt in the visible light region, there are polymethylene dyes such as cyanine dyes or styryl dyes, pyrylium dyes, xanthene dyes. , Triphenylmethane dyes, azulene dyes and the like. Among these dyes, polymethylene dyes are preferred because of their excellent sensitizing effect on the aromatic onium salt (claim 8), and cyanine dyes or styryl dyes are particularly preferred (claim 9). . Further, when a polymethylene dye is applied as a sensitizer, its counter anion is P
An inorganic anion selected from F ₆ ⁻ , SbF ₆ ⁻ and BF ₄ ⁻ ,
Or,

[0038]

Embedded image When it is an organic anion selected from the above, its solubility is excellent (claim 10).

Specific examples of the cationic dye sensitizer will be given below. Examples of the cyanine dye include 3-ethyl-2.
-[(3-Ethyl-2-benzothiazolinylidene) methyl] benzothiazolium, 1,3,3-trimethyl-2
-[(1,3,3-Trimethyl-2-indolinylidene) methyl] -3H-indolium, 3-ethyl-2-
[(1-Ethyl-2 (1H) -quinolilidene) methyl]
Benzothiazolium, 3-ethyl-2-[(1-ethyl-2 (1H) -quinolilidene) methyl] benzoserazolium, 1-ethyl-2-[(1-ethyl-2 (1H))
-Quinolilidene) methyl] quinolinium, 1-ethyl-
2-[(1-Ethyl-4 (1H) -quinolilidene) methyl] quinolinium, 1-ethyl-4-[(1-ethyl-
4 (1H) -quinolilidene) methyl] quinolinium, 3
-Ethyl-2- [3- (3-ethyl-2-thiazolidinylidene) -1-propenyl] thiazolinium, 3-ethyl-2- [3- (3-ethyl-2-benzoxazolinylidene)- 1-propenyl] benzoxazolium, 3-ethyl-2- {2-[(3- (3-ethyl-5-phenyl-2-benzoxazolinylidene) methyl] -1-butenyl} -5-phenyl Benzoxazolium, 5,6-dichloro-1,3-diethyl-2- [3- (5,6-dichloro-1,3-diethylbenzimidazolinylidene) -1
-Propenyl] benzimidazolium, 1,3,3-trimethyl-2- [3- (1,3,3-trimethyl-2-
Indolinylidene) -1-propenyl] -3H-indolium, 3-ethyl-2 {2-[(3-ethyl-2-benzothiazolinylidene) methyl] -1-butenyl} benzothiazolium, 3 -Ethyl-2- [3- (3-ethyl-2-benzothiazolinylidene) -2-methyl-1-propenyl] benzothiazolium, 2- {2-methyl-3
-[3- (3-Sulfopropyl) -2-benzoselenazolinylidene] -1-propenyl} -3- (3-sulfopropyl) benzoselenazolium, 3-ethyl-4-methyl-2- [3 -(3-Ethyl-4-methyl-2-thiazolinylidene) -1-propenylthiazolium, 3-ethyl-2- [3- (3-ethyl-2-benzothiazolinylidene) -1-propenyl] benzo Thiazolium, 3-
(3-Sulfopropyl) -2- {3- [3- (3-sulfopropyl) -2-benzothiazolinylidene] -1-propenyl} benzothiazolium, 3-ethyl-2- [3
-(3-Ethyl-2-benzoselenazolinylidene) -1
-Propenyl] benzoselenazolium, 2- {2-methyl-3- [3- (3-sulfopropyl) -2-naphtho [1,2-d] thiazolinylidene] -1-propenyl}
-3- (3-Sulfopropyl) naphtho [1,2-d] thiazolium, 3-ethyl-2- [3- (3-ethyl-2)
-Naphtho [2,1-d] thiazolinylidene) -2-methyl-1-propenyl] naphtho [2,1-d] thiazolium, 3-ethyl-2- {2-[(3-ethyl-2-naphtho [2 , 1-d] Thiazolinylidene) methyl] -1-butenyl} naphtho [2,1-d] thiazolium, 3-ethyl-2- {2-[(3-ethyl-2-naphtho [1,2-
d] thiazolinylidene) methyl] -1-butenyl} naphtho [1,2-d] thiazolium, 1,1,3-trimethyl-2- [3- (1,1,3-trimethylbenzindoline-2-ylidene)- 1-propenyl] -1H-benzindolium, 3-ethyl-2- [3- (3-ethyl-2-naphtho [2,1-d] thiazolinylidene) -1-
Propenyl} naphtho [2,1-d] thiazolium, 3-
Ethyl-2- [3- (1-ethyl-4 (1H) -quinolilidene) -1-propenyl] benzoxazolium, 3-
Ethyl-2- [3- (3-ethyl-2-naphtho [1,2
-D] thiazolinylidene) -1-propenyl] naphtho [1,2-d] thiazolium, 1-ethyl-2- [3-
(1-Ethyl-2 (1H) -quinolilidene) -1-propenyl] quinolinium, 3-ethyl-2- [3- (1-
Ethyl-4 (1H) -quinolilidene) -1-propenyl] benzothiazolium, 1-ethyl-2- [3- (1
-Ethyl-4 (1H) -quinolilidene) -1-propenyl] quinolinium, 1-ethyl-4- [3- (1-ethyl-4 (1H) -quinolilidene) -1-propenyl] quinolinium, 3-ethyl-2 -[5- (3-ethyl-2
-Benzoxazolinylidene) -1,3-pentadienyl] benzoxazolium, 1,3,3-trimethyl-
2- [5- (1,3,3-trimethyl-2-indolinylidene) -1,3-pentadienyl] -3H-indolium, 3-ethyl-2- [5- (3-ethyl-2-benzo) Thiazolinylidene) -1,3-pentadienyl] benzothiazolium, 3-ethyl-2-{[3- (3-ethyl-2-benzothiazolinylidene) methyl] -5,5-
Dimethyl-2-cyclohexene-1ylidene] methyl}
Benzothiazolium, 3-ethyl-2- [5- (3-ethyl-2-benzoselenazolinylidene) -1,3-pentadienyl] benzoselenazolium, 1,1,3-trimethyl-2- [ 5- (1,1,3-Trimethylbenzindoline-2-ylidene) -1,3-pentadienyl]
-1H-benzindolium, 3-ethyl-2- [5-
(3-Ethyl-2-naphtho [2,1-d] thiazolinylidene) -1,3-pentadienyl] naphtho [2,1-
d] thiazolium, 3-ethyl-2- [5- (3-ethyl-2-naphtho [1,2-d] thiazolinylidene)-
1,3-pentadienyl] naphtho [1,2-d] thiazolium, 1-ethyl-2- [3-chloro-5- (1-ethyl-2 (1H) -quinolilidene) -1,3-pentadienyl] quinolinium, 1-ethyl-2- [5- (1-
Ethyl-2 (1H) -quinolilidene) -1,3-pentadienyl] quinolinium, 1-ethyl-4- [3-chloro-5- (1-ethyl-4 (1H) -quinolilidene)-
1,3-Pentadienyl] quinolinium, 1-ethyl-
4- [5- (1-ethyl-4 (1H) -quinolilidene)
-1,3-Pentadienyl] quinolinium, 3-ethyl-2- [7- (3-ethyl-2-benzoxazolinylidene) -1,3,5-heptatrienyl] benzoxazolium, 1,3,3 -Trimethyl-2- [7- (1,
3,3-trimethyl-2-indolinylidene) -1,
3,5-heptatrienyl] -3H-indolium,
3,3-dimethyl-2- [7- (3,3-dimethyl-1
-(3-Sulfopropyl) -2-indolinylidene]-
1,3,5-Heptatrienyl] -1- (3-sulfopropyl) -3H-indolium, 3-ethyl-2- [7
-(3-Ethyl-2-benchazolinylidene) -1,
3,5-heptatrienyl] benzothiazolium, 3-
Ethyl-2- [7- (3-ethyl-2-benzothiazolinylidene) -1,3,5-heptatrienyl] benzothiazolium, 3-ethyl-2- [7- (3-ethyl-2)
-Benzoselenazolinylidene) -1,3,5-heptatrienyl] benzoselenazolium, 1,1,3-trimethyl-2- [7- (1,1,3-trimethylzendoindolin-2-ylidene)- 1,3,5-Heptatrienyl] -1H-zenzindolium, 3-ethyl-2-
[7- (3-Ethyl-2-naphtho [1,2-d] thiazolinylidene) -1,3,5-heptatrienyl] naphtho [1,2-d] thiazolium, 1-ethyl-2- [7-
(1-Ethyl-2 (1H) -quinolilidene) -1,3,
5-heptatrienyl] quinolinium, 1-ethyl-4
-[7- (1-Ethyl-4 (1H) -quinolilidene)-
1,3,5-heptatrienyl] quinolinium, 2-
{[3-allyl-5- [2- (5,6-dimethyl-3-
n-Propyl-2-benzothiazolinylidene) ethylidene] -4-exo-2-thiazolidiylidene] methyl}
-3-Ethyl-4,5-diphenylthiazolium, 3-
Ethyl-2-{[3-ethyl-5- [2- (1-ethyl-4 (1H) -quinolilidene) ethylidene] -4-exo-2-thiazolidinylidene] methyl} benzoxazolium, 3- Ethyl-2-{[3-ethyl-5- [2-
(1-Ethyl-4 (1H) -quinolilidene) ethylidene] -4-exo-2-thiazolidinilidene] methyl}
Iodides such as 4,5-diphenylthiazolium,
Bromide, chloride, hexafluoroantimonate,
Hexafluorophosphate, tetrafluoroborate, hexafluoroarsenate, p-toluenesulfonate, trifluoromethanesulfonate, methanesulfonate, perchlorate salt and the like can be mentioned, but not limited thereto.

Further, examples of the styryl dye include
2- (p-dimethylaminostyryl) -1-ethylpyridinium, 2- (p-dimethylaminostyryl) -3-
Methylbenzoxazolium, 2- (p-dimethylaminostyryl) -3-ethylbenzoxazolium, 2- (p
-Dimethylaminostyryl) -3-ethylselenazolium, 2- (p-dimethylaminostyryl) -1-ethylquinolinium, 2- (p-dimethylaminostyryl)-
3-ethylnaphtho [1,2-d] thiazolium, 2-
(P-Dimethylaminostyryl) -1,3,3-trimethyl-3H-indolium, 4- (p-dimethylaminostyryl) -1-ethylquinolinium, 2- [4- (p
-Dimethylaminophenyl) -1,3-butadienyl]
-1-ethylquinolinium, 2- [4- (p-dimethylaminophenyl) -1,3-butadienyl] -3-ethylnaphtho [1,2-d] thiazolium, 2- [4- (p
-Dimethylaminophenyl) -1,3-butadienyl]
-3-ethylbenzothiazolium, 4- [4- (p-dimethylaminophenyl) -1,3-butadienyl] -1
-Iodide such as ethylquinolinium, bromide, chloride, hexafluoroantimonate, hexafluorophosphate, tetrafluoroborate, hexafluoroarsenate, p-toluene smefonate, trifluoromethanesulfonate, methanesulfonate, perchlorate salt, etc. However, the present invention is not limited to these.

Further, as the above-mentioned pyrylium dye, 2
-Amino-4,6-bis (4-butoxyphenyl) thiopyrylium, 2-hydroxy-4,6-bis (4-dimethylaminostyryl) pyrylium, 2-hydroxy-
4,6-bis (4-dimethylaminostyryl) thiopyrylium, 2-amino-4,6-bis (4-butoxyphenyl) pyrylium, 2-amino-4,6-bis (4-methoxy-β-ethylstyryl) Examples include iodide such as thiopyrylium, bromide, chloride, hexafluoroantimonate, hexafluorophosphate, tetrafluoroborate, hexafluoroarsenate, p-toluene smefonate, trifluoromethanesulfonate, methanesulfonate and perchlorate salt. It is not limited to these.

As an example of the above xanthene dye, [2,7-dimethyl-9- (o-ethoxycarbonylphenyl) -6-ethylamino-3H-xanthene-
3-ylidene] ethylammonium, [9- (o-carbonylphenyl) -6-diethylamino-3H-xanthene-3-ylidene] diethylammonium, [6-diethylamino-9- (2,4-sulfonyl) -3H-xanthene -3-ylidene] diethylammonium, [9
-(O-Carbonylphenyl) -6-amino-3H-xanthene-3-ylidene] ammonium, [9- (o-
Ethoxycarbonylphenyl) -6-ethylamino-3
H-xanthene-3-ylidene] ethylammonium,
[9- (o-methoxyphenyl) -6-amino-3H-
Xanthene-3-ylidene] ammonium, [9- (o
-Carbonylphenyl) -6-diethylamino-3H-
Xanthene-3-ylidene] dimethylammonium,
[9- (o-Ethoxycarbonylphenyl) -6-diethylamino-3H-xanthene-3-ylidene] diethylammonium, [2,7-dimethyl-9- (o-carboxyphenyl) -6-ethylamino-3H-xanthene -3-Ylidene] ethylammonium iodide, bromide, chloride, hexafluoroantimonate, hexafluorophosphate, tetrafluoroborate, hexafluoroarsenate, p-toluene smefonate, trifluoromethanesulfonate, methanesulfonate, perchlorate salt Other examples include fluorescein and its derivatives, erythrosine, and rose bengal, but are not limited to these.

As the above-mentioned triphenylmethane type dye, bis (p-dimethylaminophenyl) phenyl-
2-methylmethylium, bis (p-dimethylaminophenyl) phenyl-3-methylmethylium, bis (p-dimethylaminophenyl) phenyl-4-hydroxymethylium, bis (p-dimethylaminophenyl) phenyl-3- Cyanomethylium, bis (p-dimethylaminophenyl) phenyl-4-cyanomethylium, bis (p-
Dimethylaminophenyl) phenyl-2,6-dimethylmethylium, bis (p-dimethylaminophenyl) phenyl-2 ', 4-dimethylmethylium, bis (p-dimethylaminophenyl) phenyl-4-methylaminomethylium, Bis (p-dimethylaminophenyl) phenyl-4-methoxymethylium, bis (p-dimethylaminophenyl) phenylmethylium, bis (p-dimethylaminophenyl) phenyl-2-nitromethylium, bis (p-dimethylamino) Phenyl) phenyl-4-nitromethylium, bis (p-dimethylaminophenyl) phenyl-2,4-dimethoxymethylium, bis (p-dimethylaminophenyl) phenyl-2,6-dimethoxymethylium, bis (p- Dimethylaminophenyl) phenyl-2-t-butyl Methylium, bis (p-dimethylaminophenyl) phenyl-3,5-dimethoxymethylium, tris (p-dimethylaminophenyl) methylium, tris (p-dimethylaminophenyl) -2,6-
Dimethoxymethylium, bis (p-diethylaminophenyl) phenyl-2-methylmethylium, bis (p-diethylaminophenyl) phenyl-4-methoxymethylium, bis (p-dimethylaminophenyl)-[4-
(N-methyl-N-phenylamino) -1-naphthyl]
Iodide such as methylium and tris (p-aminophenyl) methylium, bromide, chloride, hexafluoroantimonate, hexafluorophosphate, tetrafluoroborate, hexafluoroarsenate,
Examples thereof include p-toluene smefonate, trifluoromethanesulfonate, methanesulfonate, perchlorate salt, etc., but are not limited thereto.

Specific examples of the azulene dye include 1,3-bis (guaiazulenyl) propenium,
1,3-bis (6-t-butylazurenyl) propenium, 1,5-bis (guaiazulenyl) pentadienium, 1-guaiazulenyl-5- (6′-t-butylazurenyl) pentadienium, 1-guaiazulenyl-
Iodide such as 5- (6′-octylazurenyl) pentadienium, bromide, chloride, hexafluoroantimonate, hexafluorophosphate, tetrafluoroborate, hexafluoroarsenate, p-
Examples thereof include, but are not limited to, toluene smefonate, trifluoromethanesulfonate, methanesulfonate, perchlorate salt, and the like.

The above-mentioned sensitizers may be applied as a mixture of two or more kinds, if necessary.

Next, a specific example of the ammonium borate salt represented by the above general formula (I) and compounded in the photosensitive resin composition for hologram recording of the present invention is tetramethylammonium-n-butyltriphenylborate. Tetramethylammonium-n-butyltrianisyl borate,
Tetraethylammonium-n-butyltriphenylborate, tetraethylammonium-n-butyltrianisylborate, tetrabutylammonium-n-butyltriphenylborate, tetrabutylammonium-
n-Butyltrianisyl borate, tetramethylammonium-n-octyltriphenylborate, tetramethylammonium-n-octyltrianisylborate, tetraethylammonium-n-octyltriphenylborate, tetraethylammonium-n-octyltrianisylborate, tetra Butyl ammonium-
n-octyltriphenylborate, tetrabutylammonium-n-octyltrianisylborate, trimethylammonium-n-butyltriphenylborate,
Examples thereof include triethylammonium-n-butyltriphenylborate and ammonium-n-butyltriphenylborate, but the invention is not limited thereto.

As described above, a solvent-soluble, cationically polymerizable thermosetting epoxy oligomer and at least one radically polymerizable ethylenically unsaturated bond which is liquid at room temperature and pressure and has a boiling point of 100 ° C. or higher at normal pressure. With one or more aliphatic monomers, an aromatic onium salt that generates a Bronsted acid or Lewis acid that activates radical polymerization and cationic polymerization when exposed to actinic radiation, and an aromatic onium salt The photosensitive resin composition for hologram recording according to the present invention, which comprises, as a main component, a cationic dye sensitizer capable of sensitizing the above in a visible light region and an ammonium borate salt represented by the general formula (I),
It has good sensitivity to coherent light having an oscillation source from the visible light region to the near infrared light region (400 nm or more) such as argon laser, helium-cadonium laser, helium-neon laser, krypton laser, and semiconductor laser. ing.

Then, the above-mentioned respective components are appropriately selected, and the photosensitive solution obtained by mixing them at an arbitrary ratio is used in principle by using a spin coater, a roll coater, a bar coater or the like, a glass plate, a polycarbonate plate or a polymethyl plate. A hologram recording medium according to the present invention is provided by applying a film on a substrate such as a methacrylate plate or a polyester film to form a photosensitive layer, and providing an oxygen barrier film on the photosensitive layer. As the oxygen barrier film, for example, a film equivalent to the above substrate, or a plastic such as polyolefin, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol or polyethylene terephthalate, and an optically transparent film such as glass are used to form the photosensitive layer. It is formed by sandwiching and laminating, stacking with an extruder, coating a solution, and the like. When the photosensitive solution is applied, it may be diluted with an appropriate solvent if necessary, but in that case, it is necessary to dry it after applying it on the substrate. Further, it is desirable to adjust the transmittance of the irradiation light at the time of photographing to be 1% or more. Examples of the solvent that can be applied when preparing a photosensitive solution include thermosetting epoxy oligomers, aliphatic monomers, aromatic onium salts, cationic dye sensitizers and the above general formula (I).
All of the components of ammonium borate shown in can be dissolved, and the substrate to be coated is not likely to be affected by dissolution, swelling, clouding, erosion, etc., and most commonly used organic solvents can be used. Can be used.
Specifically, methanol, ethanol, propanol,
Isopropyl alcohol, n-butanol, t-butanol, 2-methylpropyl alcohol, chloroform,
Dichloromethane, carbon tetrachloride, 1,4-dioxane, tetrahydrofuran, acetone, ethyl methyl ketone, ethyl acetate, acetonitrile, toluene, xylene, cyclohexane, cyclohexanone, n-pentane, n-heptane, n-hexane, 2-methoxyethanol, 2-
Ethoxyethanol, 2-butoxyethanol, 2-ethoxyethyl acetate, 2-butoxyethyl acetate, 2-methoxyethyl acetate, 2-ethoxyethyl ether, 2- (2-ethoxyethoxy) ethanol, 2- (2-butoxyethoxy) Ethanol, 2-
(2-Ethoxyethoxy) ethyl acetate, 2- (2
-Butoxyethoxy) ethyl acetate, 2-phenoxyethanol, diethylene glycol dimethyl ether, etc. are exemplified, but not limited thereto.
Any solvent having the above-mentioned requirements can be applied. Further, if necessary, two or more kinds of solvents can be mixed and used.

Then, the above-mentioned photosensitive layer of the hologram recording medium thus obtained is subjected to holographic exposure to form a latent image, and then heated at 60 ° C. to 120 ° C. for 1 to 30 minutes. A volume phase hologram can be manufactured by performing the treatment (claim 12).

Regarding the compounding ratio of the aliphatic monomer in the photosensitive resin composition for hologram recording according to the present invention,
10 to 100 parts by weight of thermosetting epoxy oligomer
It is possible to range from 10 to 100 parts by weight, preferably 20 to 80 parts by weight (claim 6). If the amount is less than 10 parts by weight, the amount of monomer polymerized by holographic exposure with a laser in the visible light region to the near infrared light region (400 nm or more) tends to be insufficient, so that high refractive index modulation cannot be obtained even after heat treatment, which is bright. A hologram may not be obtained, which is not preferable. Also, 1
If it exceeds 100 parts by weight, the amount of the monomer becomes excessive, and it becomes difficult for the polymerization to occur in the first holographic exposure, and the amount of the monomer remaining in the system increases. As a result, during heating in the manufacturing process, polymerization is likely to occur while diffusing, and along with this, interference fringes of the hologram once formed are disturbed and high refractive index modulation cannot be obtained, and a bright hologram may not be obtained. .

The amount of the aromatic onium salt in the photosensitive resin composition for hologram recording is 0.1 to 20 parts by weight, preferably 1 to 10 parts by weight, based on 100 parts by weight of the thermosetting epoxy oligomer. Is. The mixing ratio of the cationic dye sensitizer is set to about 0.1 to 10 parts by weight with respect to 100 parts by weight of the thermosetting epoxy oligomer. The mixing amount depends on the film thickness of the photosensitive layer and Limited by the optical density of the film thickness. That is, it is preferably used within a range where the optical density does not exceed 2.
On the other hand, the addition amount of the ammonium borate salt represented by the general formula (I) is 0.05 to 20 parts by weight, preferably 0.5 to 1 part by weight with respect to 1 part by weight of the cationic dye sensitizer.
0 parts by weight. If the amount is less than 0.05 parts by weight, the photosensitivity decreases, and it takes a long time to expose the hologram, so that the hologram is easily affected by vibration and the like, and a bright hologram may not be obtained. If it exceeds 20 parts by weight, problems such as solubility will occur. In short, 20 parts by weight or more may be blended, if necessary, as long as the ammonium borate salt has good solubility.

Further, additives such as a thermal polymerization inhibitor, a chain transfer agent and an antioxidant may be blended in the photosensitive resin composition for hologram recording according to the present invention, if desired.

Here, when the volume phase hologram is manufactured by applying the hologram recording medium according to the present invention, the photosensitive speed becomes higher than that in the case where the hologram recording medium according to the conventional example is used, and the workability is improved. The present inventors presume as follows for the reason why the hologram characteristic value of the obtained volume phase hologram is improved as well as the above.

That is, in the photosensitive layer 3 of the hologram recording medium according to the present invention, as shown in FIG. 1A, the aliphatic monomer 32 having at least one radically polymerizable ethylenically unsaturated bond is a solvent. Although it is uniformly distributed in the soluble and cationically polymerizable thermosetting epoxy oligomer 31, laser interference light (that is, two light fluxes) from the visible light region to the near infrared light region (400 nm or more) is recorded on the photosensitive layer 3 in hologram recording. When an optical system) is irradiated, the aromatic onium salt in the photosensitive layer activates radical polymerization by the action of the cationic dye sensitizer at the site of strong light interference in the laser irradiation site. And at the same time, Bronsted acid or Lewis acid 33 which activates the cationic polymerization is generated. The radical species 34 generated here radically polymerize the aliphatic monomer 32, and a difference in concentration occurs in the photosensitive layer as it is polymerized, so that the aliphatic monomer 32 moves from the surroundings. That is,
As shown in FIG. 1 (B), the concentration of the aliphatic monomer 32 is high in the portion having strong optical interference in the laser irradiation portion, and is low in the portion having weak optical interference in the laser irradiation portion. As a result, it is estimated that the hologram recording is performed due to the difference in refractive index between the two parts.

At this time, in the present invention, an aromatic onium salt, a cationic dye sensitizer, and the above general formula (I) are used.
With the application of the ammonium borate salt shown in 1), the photosensitive speed of the photosensitive layer is improved. That is,
According to the hologram recording medium of the present invention, the cationic dye sensitizer (D ⁺ X ⁻ ) is first excited by the optical action of the laser interference light in the visible region. Next, the cationic dye sensitizer ( ^* D ⁺ X ⁻ ) in this excited state acts on the aromatic onium salt to cause decomposition of the aromatic onium salt,
A radical species and a Lewis acid or Bronsted acid are generated, and the cationic dye sensitizer is dissociated to become D ⁺ . Next, ion exchange occurs between this D ⁺ and the ammonium borate salt (B ⁻ R ₁ to ₄ · N ⁺ R ₅ to ₈ ) in the system to form D ⁺ B ⁻ R ₁ to ₄ . This new addition to acting as a sensitizer of the aromatic onium salts, produced by dissociation B ^- R ₁ ~ ₄ generates a radical species by decomposition. At this time, since D ⁺ is regenerated by ion exchange with the ammonium borate salt, it continues to function as a sensitizer. As described above, since one radical sensitizing dye can efficiently generate more radical species, the above-mentioned Japanese Patent Application No. 6-46742 developed by the present inventors.
It is inferred that the photosensitive speed can be increased as compared with the hologram recording medium described in Japanese Patent Application No. Hei 6-149,967.

Then, by performing a heat treatment after the exposure to the laser interference light, the Bronsted acid or the Lewis acid 33 generated at the same time as the radical species 34 acts on the site having a strong optical interference effect during the irradiation of the laser interference light. However, since the solvent-soluble thermosetting epoxy oligomer 31 capable of cationic polymerization undergoes cationic polymerization according to the light intensity distribution and has a structure with different cross-linking densities (see FIGS. 1C and 1D), there is an optical interference effect in the laser irradiation site. It is estimated that the difference in refractive index between the strong part and the weak part can be further increased, and a volume phase hologram with high diffraction efficiency can be obtained unlike the above-mentioned prior art.

Further, since the thermosetting epoxy oligomer serving as the support has a crosslinked structure by cationic polymerization, the weatherability and chemical stability of the volume phase hologram obtained are also improved.

However, after the holographic exposure and before the heat treatment, the entire surface is exposed to ultraviolet rays or other actinic radiation (electron rays, X rays, visible rays, infrared rays, etc.) to heat-cure the thermosetting epoxy oligomer. The improvement in diffraction efficiency due to is no longer observed. It is inferred that the reason is that Bronstedted acid or Lewis acid 33 is uniformly generated at the irradiation site by the whole surface exposure and the crosslinking density becomes uniform due to this.

[0059]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to specific examples.

Example 1 Bisphenol A type epoxy resin Epicoat 1007 [trade name of Yuka Shell Epoxy Co., Ltd.] 100 parts by weight, triethylene glycol diacrylate 50 parts by weight and diphenyliodonium hexafluorophosphate 5 parts by weight. , 2- (p-dimethylaminostyryl) -3-ethylbenzoxazolium tetrafluoroborate (sensitizing dye: S-1) 0.35
By mixing 1 part by weight of tetramethylammonium n-butyltriphenylborate with 220 parts by weight of 2-butanone and 20 parts by weight of ethanol, a solution was prepared. This sensitizing solution was applied to a glass plate so that the film thickness was about 15 μm, dried at 100 ° C. for 5 minutes, and then P
An ET film was provided with an air barrier layer (oxygen barrier film) to prepare a hologram recording medium.

This hologram recording medium was subjected to PET using an immersion liquid (trade name: Isopar manufactured by Esso Petrochemical Co., Ltd.).
Make sure that the surface (air barrier layer) is facing down and adhere to the mirror. Then, an argon laser (514.5 nm) was used as a light source, and the volume phase hologram was prepared by exposing with a light expanded to an area slightly larger than the area of the mirror (for the exposure amount, see Table 1 below), and then at 100 ° C. It heat-processed for 30 minutes.

The diffraction efficiency was measured with a spectrophotometer UV-160 (trade name) manufactured by Shimadzu Corporation. That is, monochromatic light was incident on the sample at an angle of 5 degrees, and diffracted light from the sample was detected. The measured reflected light was directly used as the diffraction efficiency. The diffraction efficiency at that time was 92%, and the refractive index modulation was 0.0.
It was 222.

[Embodiment 2-10] In Embodiment 1, 2
Instead of 3- (p-dimethylaminostyryl) -3-ethylbenzoxazolium tetrafluoroborate (S-1), 3-ethyl-2-[(1-ethyl-2 (1H)-
Quinolilidene) methyl] benzothiazolium hexafluorophosphate (S-2), 3,3'-dihydroxyethyl-5,5'-dimethyl-9-ethyl-2,2 '
-Thiacarbocyanine hexafluorophosphate (S-3), 3-ethyl-2- {2-[(3- (3-ethyl-5-phenyl-2-benzoxazolinylidene) methyl] -1-butenyl} -5-phenyl benzoxazolium iodide (S-4), 2- (p-dimethylaminostyryl) -1,3,3-trimethyl-3H-indolium iodide (S-5), 2- [4- ( p
-Dimethylaminophenyl) -1,3-butadienyl]
-3-Ethylnaphtho [1,2-d] thiazolium hexafluorophosphate (S-6), 2- [4- (p-
Dimethylaminophenyl) -1,3-butadienyl]-
3-Ethylbenzothiazolium iodide (S-
7), 3-ethyl-2- [3- (3-ethyl-2-benzoxazolinylidene) -1-propenyl] benzoxazolium methanesulfonate (S-8), 2-hydroxy-4,6- A volume phase hologram was prepared in the same manner as in Example 1 except that bis (4-dimethylaminostyryl) thiopyrrolinium tetrafluoroborate (S-9) or erythrosine (S-10) was used. And,
The same evaluation test was performed.

The evaluation results are shown in Table 1 together with the results of Example 1.

Incidentally, D. E. FIG. (%) And R. I.
M. (× 100) indicates diffraction efficiency and refractive index modulation, respectively.

[0066]

[Table 1] S-1; 2- (p-dimethylaminostyryl) -3-ethylbenzoxazolium tetrafluoroborate S-2; 3-ethyl-2-[(1-ethyl-2 (1H))
-Quinolilidene) methyl] benzothiazolium hexafluorophosphate S-3; 3,3'-dihydroxyethyl-5,5'-dimethyl-9-ethyl-2,2'-thiacarbocyanine
Hexafluorophosphate S-4; 3-ethyl-2- {2-[(3- (3-ethyl-5-phenyl-2-benzoxazolinylidene) methyl] -1-butenyl} -5-phenylbenzoxa Zolium iodide S-5; 2- (p-dimethylaminostyryl) -1,
3,3-Trimethyl-3H-indolium iodide S-6; 2- [4- (p-dimethylaminophenyl)-
1,3-Butadienyl] -3-ethylnaphtho [1,2-
d] thiazolium hexafluorophosphate S-7; 2- [4- (p-dimethylaminophenyl)-
1,3-Butadienyl] -3-ethylbenzothiazolium iodide S-8; 3-ethyl-2- [3- (3-ethyl-2-benzoxazolinylidene) -1-propenyl] benzoxazolium Methanesulfonate S-9; 2-Hydroxy-4,6-bis (4-dimethylaminostyryl) thiopyrrinium tetrafluoroborate S-10; Erythrosine

[Embodiment 11-16] In Embodiment 1,
Bisphenol A type epoxy resin Epicoat 1007
[Yukaka Shell Epoxy Co., Ltd. trade name] (epoxy oligomer), instead of a thermosetting epoxy oligomer (trade name "EBPS300" manufactured by Nippon Kayaku Co .; P-1), novolac type thermosetting epoxy oligomer ( Product name "EPPN
-201 "manufactured by Nippon Kayaku Co., Ltd .; P-2), a brominated novolac type thermosetting epoxy oligomer (trade name" BREN- ").
S "manufactured by Nippon Kayaku Co., Ltd .; P-3), o-cresol novolac type thermosetting epoxy oligomer (trade name" EOCN- ").
104 "manufactured by Nippon Kayaku Co .; P-4), alicyclic thermosetting epoxy oligomer (trade name" ST-5080 "manufactured by Toto Kasei Co .; P-5) or (trade name" ST-5100 "Toto Kasei Co., Ltd.) P-6) was used to prepare a photosensitive solution by dissolving it in a mixed solvent consisting of 100 parts by weight of 2-butanone and 10 parts by weight of ethanol, to prepare a volume phase hologram in the same manner as in Example 1. Then, the same evaluation test was performed.

The evaluation results are shown in Table 2.

[0069]

[Table 2] P-1; trade name "EBPS300" manufactured by Nippon Kayaku Co., Ltd. P-2; trade name "EPPN-201" manufactured by Nippon Kayaku Co., P-3; trade name "BREN-S" manufactured by Nippon Kayaku Co., P-4; Product name "EOCN-104" manufactured by Nippon Kayaku Co., Ltd. P-5; Product name "ST-5080" manufactured by Toto Kasei Co., Ltd. P-6; Product name "ST-5100" manufactured by Toto Kasei Co., Ltd.

[Embodiment 17-23] In Embodiment 1,
2- (p-dimethylaminostyryl)-which is a sensitizing dye
2- [4- (p-Dimethylaminophenyl) -1,3-butadienyl] -3-ethylnaphtho [1,2-d] thiazolium instead of 3-ethylbenzoxazolium tetrafluoroborate (S-1) Hexaflufluorophosphate (S-6), 2- [4- (p-dimethylaminophenyl) -1,3-butadienyl] -3-ethylbenzothiazolium iodide (S-7), 3-ethyl-2- {[3-Ethyl-5- [2- (1-ethyl-4
(1H) -quinolilidene) ethylidene] -4-exo-
2-Thiazolidinylidene] methyl} benzoxazolium tetrafluoroborate (S-11), 3-ethyl-
2- [5- (3-ethyl-2-benzothiazolinylidene) -1,3-pentadienyl] benzothiazolium
Tosylate (S-12), 3-ethyl-2- [7- (3
-Ethyl-2-benzoxazolinylidene) -1,3,
5-heptatrienyl] benzoxazolium iodide (S-13), 3-ethyl-2- [3- (1-ethyl-4 (1H) -quinolilidene) -1-propenyl]
A sensitizing solution was prepared using benzothiazolium iodide (S-14) and bis (p-dimethylaminophenyl) phenylmethylium (S-15), and a krypton laser (647.9 nm) was used instead of an argon laser. A volume phase hologram was produced in the same manner as in Example 1 except that the above was used, and the same evaluation test was performed.

Table 3 shows the evaluation results.

[0072]

[Table 3] S-6; 2- [4- (p-dimethylaminophenyl)-
1,3-Butadienyl] -3-ethylnaphtho [1,2-
d] thiazolium hexafluorophosphate S-7; 2- [4- (p-dimethylaminophenyl)-
1,3-Butadienyl] -3-ethylbenzothiazolium iodide S-11; 3-ethyl-2-{[3-ethyl-5- [2-
(1-Ethyl-4 (1H) -quinolilidene) ethylidene] -4-exo-2-thiazolidinilidene] methyl}
Benzoxazolium tetrafluoroborate S-12; 3-ethyl-2- [5- (3-ethyl-2-benzothiazolinylidene) -1,3-pentadienyl] benzothiazolium tosylate S-13; 3 -Ethyl-2- [7- (3-ethyl-2-benzoxazolinylidene) -1,3,5-heptatrienyl] benzoxazolium iodide S-14; 3-ethyl-2- [3- (1 -Ethyl-4 (1
H) -quinolilidene) -1-propenyl] benzothiazolium iodide S-15; bis (p-dimethylaminophenyl) phenylmethylium

[Embodiment 24-31] In the second embodiment,
Instead of diphenyliodonium hexafluorophosphate (aromatic onium salt) and tetramethylammonium n-butyltriphenylborate (ammonium borate salt), use the combination of the aromatic onium salt and ammonium borate salt shown in Table 4. A volume phase hologram was prepared in the same manner as in Example 2 except for the above, and the same evaluation test was performed.

Table 4 shows the evaluation results.

[0075]

[Table 4] B-1; Tetramethylammonium n-butyltriphenylborate B-2; Tetramethylammonium n-butyltrianisylborate B-3; Tetraethylammonium n-butyltriphenylborate B-4; Tetramethylammonium n-octyltriphenyl Borate B-5; Tetramethylammonium n-octyltrianisylborate D-1; Bis (p-tert-butylphenyl) yo
Donium hexafluorophosphate D-2; Diphenyliodonium tetrafluoroborate D-3; Diphenyliodonium trifluoromethanesulfonate D-4; Tri (4-methoxyphenyl) phosphonium
Tetrafluoroborate D-5: Iron arene complex (Irgacure 261; trade name manufactured by Ciba Geigy)

[Embodiments 32-38] In the first embodiment,
Instead of triethylene glycol diacrylate, diethylene glycol diacrylate (DEGDA), tripropylene glycol diacrylate (TPGD
A), neopentyl glycol diacrylate (NPG
DA), ethyl carbitol acrylate (EKA),
1,6-hexanediol diacrylate (HDD
A), trimethylolpropane triacrylate (TM)
A volume phase hologram was prepared in the same manner as in Example 1 except that PTA) or triethylene glycol dimethacrylate (TEGDMA) was used, and the same evaluation test was performed.

The evaluation results are shown in Table 5.

[0078]

[Table 5] DEGDA; diethylene glycol diacrylate TPGDA; tripropylene glycol diacrylate NPGDA; neopentyl glycol diacrylate EKA; ethyl carbitol acrylate HDDA; 1,6-hexanediol diacrylate TMPTA; trimethylolpropane triacrylate TEGDMA; triethylene glycol dimethacrylate

[Comparative Example 1-10] A volume phase hologram was prepared in the same manner as in Examples 1 to 10 except that tetramethylammonium n-butyltriphenylborate (ammonium borate salt) was not added, and The same evaluation test was performed.

The evaluation results are shown in Table 6.

[0081]

[Table 6] *) No hologram was obtained.

[Comparative Examples 11 to 20] Volume phase holograms were prepared in the same manner as in Examples 1 to 10 except that diphenyliodonium hexafluorophosphate (aromatic onium salt) was not added, and the same results were obtained. An evaluation test was conducted.

The results of this evaluation are shown in Table 7.

[0084]

[Table 7] *) No hologram was obtained.

[Confirmation] Exposure amount (mJ / cm ² ) at the time of hologram recording of each Example and Comparative Example and the diffraction efficiency [D. E. FIG. (%)] And refractive index modulation [R. I. M. As is clear from the data of (× 100)], it was confirmed that neither the aromatic onium salt nor the ammonium borate salt could be improved in the photosensitivity and the hologram characteristic value.

[0086]

According to the inventions of claims 1 to 12, a solvent-soluble thermosetting epoxy oligomer capable of cationic polymerization, a liquid at normal temperature and pressure and a boiling point of 100 ° C. at normal pressure.
An aliphatic monomer having at least one radically polymerizable ethylenically unsaturated bond as described above, a radical species that activates radical polymerization when exposed to actinic radiation, and a Bronsted acid that activates cationic polymerization or An aromatic onium salt generating a Lewis acid,
Since it contains a cationic dye sensitizer capable of sensitizing an aromatic onium salt in the visible light region and an ammonium borate salt represented by the above general formula (I) as main components, it can be used in visible light, particularly argon laser, krypton. Photosensitive resin for hologram recording, which has high sensitivity to laser, helium-neon laser and semiconductor laser, is excellent in weather resistance and storage stability, and has better hologram characteristic values such as resolution, diffraction efficiency and transparency. The composition, the hologram recording medium, and the hologram manufacturing method using the hologram recording medium can be provided.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram for explaining a reaction mechanism of a hologram recording medium according to the present invention.

[Explanation of symbols]

 3 Photosensitive Layer 31 Thermosetting Epoxy Oligomer 32 Aliphatic Monomer 33 Bronsted Acid or Lewis Acid 34 Radical Species

Claims (12)

[Claims] 1. A solvent-soluble thermosetting epoxy oligomer which is cationically polymerizable and at least one radically polymerizable ethylenically unsaturated bond which is liquid at room temperature and pressure and has a boiling point of 100 ° C. or higher at normal pressure. An aliphatic onium salt having the above, an aromatic onium salt which generates a Bronsted acid or a Lewis acid which activates radical species and cationic polymerization which activate radical polymerization when exposed to actinic radiation, and an aromatic onium salt, A photosensitive resin composition for hologram recording, comprising a cationic dye sensitizer capable of sensitizing in a visible light region and an ammonium borate salt represented by the general formula (I) as main components. Embedded image (In the formula, R ₁ , R ₂ , R ₃ and R ₄ each independently represent an alkyl group, an aryl group, an alkoxyl group, an allyl group, an alkenyl group, an alkynyl group, an alicyclic group or a heterocyclic group. , R ₅ , R ₆ , R ₇ and R ₈ each independently represent an alkyl group, an aryl group, an alkoxyl group, an allyl group, an alkenyl group, an alkynyl group, an alicyclic group, a heterocyclic group or a hydrogen atom. ) 2. The thermosetting epoxy oligomer is a thermosetting epoxy oligomer represented by the general formula (II): (Wherein R ₉ and R ₁₀ each represent a hydrogen atom or a functional group selected from a methyl group, an ethyl group and a trifluoromethyl group, and the degree of polymerization is n = 1 to 20) or the general formula (III ) A thermosetting epoxy oligomer represented by: (In the formula, the degree of polymerization n = 1 to 20) or a thermosetting epoxy oligomer represented by the general formula (IV): (Wherein R ₁₁ represents a hydrogen atom or a methyl group, X represents a hydrogen atom or a halogen atom, and the degree of polymerization is n = 1 to 20), or a thermosetting epoxy oligomer represented by the general formula (V), [Chemical 5] (In the formula, R ₁₂ represents an alkyl group, and the degree of polymerization n = 1 to 20.
2. The hologram recording photosensitive resin composition according to claim 1, wherein the photosensitive recording resin composition is a hologram recording photosensitive resin composition. 3. The thermosetting epoxy oligomer is represented by the general formula (VI): (In the formula, the degree of polymerization n = 1 to 20), and
The photosensitive resin composition for hologram recording according to claim 1, which is a thermosetting bisphenol A type epoxy oligomer having an epoxy equivalent of 400 to 6000 and a melting point of 50 ° C. or higher measured by the Durance mercury method. 4. The thermosetting epoxy oligomer is represented by the general formula (VII): (Wherein R ₁₃ and R ₁₄ each represent a functional group selected from a hydrogen atom, a methyl group, an ethyl group, and a trifluoromethyl group, and the degree of polymerization is n = 1 to 20). The photosensitive resin composition for hologram recording according to claim 1, which is a curable epoxy oligomer. 5. The photosensitive material for hologram recording according to claim 1, wherein the aliphatic monomer is polyethylene glycol di (meth) acrylate or polypropylene glycol di (meth) acrylate represented by the general formula (VIII). Resin composition. Embedded image (In the formula, R _{15 to} R ₁₇ are hydrogen or a methyl group, and m,
n is 0 or more, and m + n = 1 to 20) 6. A hologram recording photosensitive material according to claim 1, wherein 20 to 80 parts by weight of an aliphatic monomer is mixed with 100 parts by weight of the thermosetting epoxy oligomer. Resin composition. 7. The photosensitive resin composition for hologram recording according to claim 1, wherein the aromatic onium salt is a diaryliodonium salt. 8. The photosensitive resin composition for hologram recording according to claim 1, wherein the cationic dye sensitizer is a polymethylene dye sensitizer. 9. The photosensitive resin composition for hologram recording according to claim 8, wherein the polymethylene dye sensitizer is a cyanine dye or a styryl dye. 10. The counter anion of the polymethylene dye sensitizer is an inorganic anion selected from PF ₆ ⁻ , SbF ₆ ⁻ , and BF ₄ ⁻ , or The photosensitive resin composition for hologram recording according to claim 8 or 9, which is an organic anion selected from the following. 11. A substrate, and a photosensitive liquid containing the photosensitive resin composition for hologram recording according to claim 1, which is applied onto the substrate.
A hologram recording medium comprising a photosensitive layer formed by drying and an oxygen barrier film provided on the photosensitive layer. 12. A holographic exposure is applied to the photosensitive layer of the hologram recording medium according to claim 11 to form a latent image, and then the latent image is formed in the range of 60 to 120 ° C.
A method for producing a hologram, which comprises producing a volume phase hologram by performing a heat treatment for 0 minutes.