JPH08101501A - Photosensitive composition for three-dimensional hologram recording, recording medium using that and forming method of three-dimensional hologram - Google Patents

Abstract

PURPOSE: To provide a photosensitive compsn. to obtain a three-dimensional hologram having high refractive index modulation and excellent heat resistance and to provide a production method of a three-dimensional hologram using this compsn. CONSTITUTION: This photosensitive compsn. for three-dimensional hologram recording is used to record interference fringes produced by interference of laser light or light having excellent coherence property as fringes of different refractive indices. The compsn. contains components of (a) cation polymerizable compd. which is liquid at normal temp., (b) radical polymerizable compd., (c) photoradical polymn. initiator which is sensitive with laser light or light having excellent coherence property to polymerize the component (b), and (d) cation polynm. initiator having heat latency.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photosensitive composition for recording a volume hologram, a recording medium using the same and a method for recording a volume hologram. More specifically, the present invention is
The present invention relates to a photosensitive composition for recording a volume hologram which gives a hologram having excellent refractive index modulation and heat resistance, and a method for recording a volume hologram which can easily produce a hologram using the same.

[0002]

2. Description of the Related Art A hologram is one in which two light beams having the same wavelength (object light and reference light) are made to interfere with each other and the wavefront of the object light is recorded as an interference fringe on a photosensitive material. When this light is applied, a diffraction phenomenon due to interference fringes occurs, and the same wavefront as the original object light can be reproduced.

Holograms are classified into several types according to the recording pattern of interference fringes. In recent years, so-called volume holograms, which record interference fringes by the difference in refractive index inside the recording layer, have high diffraction efficiency and excellent wavelength selection. Due to its properties, it is being applied to applications such as three-dimensional displays and optical elements.

As a material for recording such a volume hologram, a material using silver halide or dichromated gelatin which has been conventionally used in the art field is generally used. However, these are not suitable for industrial production of holograms because they require wet development and complicated development and fixing processing, and have a problem that the image disappears due to moisture absorption after recording. .

In order to solve these problems, it is known that a volume hologram can be produced by using a photopolymer only by a simple dry process. US Pat. Nos. 3,658,526 and 3,993,485. It has been proposed in. In addition, regarding the presumed formation mechanism of the hologram by the photopolymer, "Applied OPTICS"
(BL Booth, Volume 14, No3, P
P593-601 (1975) and W.P. J. Tomlinson
(W. J. Tomlinson), E.I. A. Chandross (EA
Chandross), Vol. 15, No. 2, PP534-54
1 (1976). However, in these techniques, the most important performance of the hologram, that is, the refractive index modulation, did not reach the above-mentioned conventional techniques.

In recent years, as a photopolymer material excellent in refractive index modulation, a photopolymer material described in JP-A-5-107999, in which a radical polymerizable compound having a different refractive index and a cation polymerizable compound are used in combination, has been proposed. There is. When this material is used, a volume hologram with a relatively large refractive index modulation can be obtained by dry processing, but 50
In an environment where a temperature of 100 ° C to 100 ° C is applied, there are problems in that the diffraction efficiency decreases with time and the reproduction wavelength changes. Therefore, it is desired to solve these problems and to develop a volume hologram that retains its initial performance even in a hot environment.

[0007]

DISCLOSURE OF THE INVENTION It is an object of the present invention to provide a photosensitive composition which gives a volume hologram having high refractive index modulation and excellent heat resistance, and a method for producing a volume hologram using the same. To aim.

[0008]

That is, the present invention relates to a photosensitive composition for volume hologram recording used for recording interference fringes produced by interference of laser light or light having excellent coherence as fringes having different refractive indexes. Wherein the composition is (a) a cationically polymerizable compound that is liquid at room temperature,
(b) a radically polymerizable compound, (c) a photoradical polymerization initiator system for polymerizing the component (b) by being exposed to the above laser beam or light having excellent coherence, and (d) a cation having a thermal potential. Provided is a photosensitive composition for volume hologram recording, which comprises each component of a polymerization initiator system.

The present invention also provides a recording medium and a volume hologram recording method using the above composition. Furthermore,
The present invention provides a hologram obtained using the above composition.

Cationic polymerizable compound used in the present invention
(a) is a radical-polymerizable compound (b) described below, which is polymerized by irradiation with laser light or light with excellent coherence (hereinafter referred to as first exposure), and then heat treatment or full exposure (the next exposure). Hereinafter, referred to as post-exposure) by cationic polymerization with a Bronsted acid or a Lewis acid generated from a cationic polymerization initiator system (d) or a photocationic polymerization initiator system (e) having thermal potential in the composition. is there. As the cationically polymerizable compound (a), a liquid compound at room temperature is used so that the radically polymerizable compound (b) is polymerized in a composition having a relatively low viscosity throughout. Examples of such a cationically polymerizable compound (a) include, for example, “Chemtech. Oct.” (J.V.
Crivello), pp. 624, (1980)], JP-A-62-
149784, Journal of Japan Adhesion Society [Vol. 26, No.
5, pp. 179-187 (1990)] and the like.

Specific examples of the cationically polymerizable compound (a) include diglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether and 1,4-bis.
(2,3-epoxypropoxyperfluoroisopropyl) cyclohexane, sorbitol polyglycidyl ether, trimethylolpropane polyglycidyl ether, resorcin diglycidyl ether, 1,6-hexanediol diglycidyl ether, polyethylene glycol diglycidyl ether, phenylglycidyl ether, Para t-butyl phenyl glycidyl ether, adipic acid diglycidyl ester, o-phthalic acid diglycidyl ester, dibromophenyl glycidyl ether, dibromo neopentyl glycol diglycidyl ether,
1,2,7,8-diepoxyoctane, 1,6-dimethylol perfluorohexane diglycidyl ether, 4,4 ′
-Bis (2,3-epoxypropoxyperfluoroisopropyl) diphenyl ether, 3,4-epoxycyclohexylmethyl-3 ', 4'-epoxycyclohexanecarboxylate, 3,4-epoxycyclohexyloxirane, 1,2,5,6- Diepoxy-4,7-methanoperhydroindene, 2- (3,4-epoxycyclohexyl)
-3 ', 4'-epoxy-1,3-dioxane-5-spirocyclohexane, 1,2-ethylenedioxy-bis (3,
4-epoxycyclohexylmethane), 4 ', 5'-epoxy-2'-methylcyclohexylmethyl-4,5-epoxy-2-methylcyclohexanecarboxylate, ethylene glycol-bis (3,4-epoxycyclohexanecarboxylate), Bis- (3,4-epoxycyclohexylmethyl) adipate, di-2,3-epoxycyclopentyl ether, vinyl-2-chloroethyl ether, vinyl-n-butyl ether, triethylene glycol divinyl ether, 1,4-cyclohexanedimethanol Divinyl ether, trimethylolethane trivinyl ether, vinyl glycidyl ether, and formula

[0012]

Embedded image The compounds represented by are listed, and one or more of them may be used.

Radical polymerizable compound used in the present invention
It is preferable that (b) has at least one ethylenically unsaturated double bond in the molecule. The average refractive index of the radically polymerizable compound (b) is preferably larger than that of the above cationically polymerizable compound (a). When the average refractive index of the compound (b) is lower than that of the compound (a), the refractive index modulation is insufficient, which is not preferable.

Specific examples of the radically polymerizable compound (b) include acrylamide, methacrylamide, styrene, 2-bromostyrene, phenyl acrylate and 2-
Phenoxyethyl acrylate, 2,3-naphthalenedicarboxylic acid (acryloxyethyl) monoester, methylphenoxyethyl acrylate, nonylphenoxyethyl acrylate, β-acryloxyethyl hydrogen phthalate, phenoxypolyethylene glycol acrylate, 2,4,6-tribromo Phenyl acrylate,
Diphenic acid (2-methacryloxyethyl) monoester,
Benzyl acrylate, 2,3-dibromopropyl acrylate, 2-hydroxy-3-phenoxypropyl acrylate, 2-naphthyl acrylate, N-vinylcarbazole, 2- (9-carbazolyl) ethyl acrylate, triphenylmethylthioacrylate, 2- ( tricyclo [5,2,10 ^2.6] dibromo decyl thio) ethyl acrylate, S- (1-naphthylmethyl) thio-acrylate, dicyclopentanyl acrylate, methylenebisacrylamide, polyethylene glycol diacrylate, trimethylol propane triacrylate, Pentaerythritol triacrylate, diphenic acid (2-acryloxyethyl) (3-acryloxypropyl-2-hydroxy) diester, 2,3-naphthalene dicarboxylic acid
(2-acryloxyethyl) (3-acryloxypropyl-2-hydroxy) diester, 4,5-phenanthrene dicarboxylic acid (2-acryloxyethyl) (3-acryloxypropyl-2-hydroxy) diester, dibromneo Pentyl glycol diacrylate, dipentaerythritol hexaacrylate, 1,3-bis [2-acryloxy-3- (2,4,6-tribromophenoxy) propoxy] benzene, diethylenedithioglycol diacrylate, 2,2-bis ( 4-acryloxyethoxyphenyl) propane, bis (4-acryloxydiethoxyphenyl) methane, bis (4-acryloxyethoxy-3,5
-Dipromophenyl) methane, 2,2-bis (4-acryloxyethoxyphenyl) propane, 2,2-bis (4-
Acryloxydiethoxyphenyl) propane, 2,2-bis (4-acryloxyethoxy-3,5-dibromophenyl) propane, bis (4-acryloxyethoxyphenyl) sulfone, bis (4-acryloxydiethoxyphenyl) Sulfone, bis (4-acryloxypropoxyphenyl) sulfone, bis (4-acryloxyethoxy-3,5
-Dibromophenyl) sulfone, and compounds in which the above-mentioned acrylate is changed to methacrylate, and further, at least two S atoms are contained in the molecule as described in JP-A-2-247205 and JP-A-2-261808. The above-mentioned compounds containing an ethylenically unsaturated double bond are included, and one or more of them may be used.

The radically polymerizable compound (b) of the present invention also has a 9,9-diarylfluorene skeleton, is liquid at room temperature, and has at least one ethylenically unsaturated double bond in the molecule. May be When this is used, high refractive index modulation is easily obtained. The radically polymerizable compound which has a 9,9-diarylfluorene skeleton and is liquid at room temperature is represented by the formula:

[0016]

Embedded image

R ₁ , R ₂ : at least one of the terminals has a radically polymerizable group such as an acryloyl group or a methacryloyl group, and this group and the benzene ring have at least one oxyethylene chain, oxypropylene chain, It is bonded via a urethane bond or an amide bond.

Specific examples of X _{1 to} X ₄ : H, alkyl group (C ₁ to X ₄
C _4), an alkoxy group (C ₁ ~C _4), an amino group, a dialkylamino group, a hydroxyl group, a carboxyl group, represented by a halogen group.

Among these, those in which an acryloyl group or a methacryloyl group in R ₁ and R ₂ is bonded to a benzene ring via an oxyethylene chain or an oxypropylene chain is particularly preferable. Specific examples of these are 9,9
-Bis (4-acryloxydiethoxyphenyl) fluorene, 9,9-bis (4-acryloxytriethoxyphenyl) fluorene, 9,9-bis (4-acryloxytetraethoxyphenyl) fluorene, 9,9-bis (4-acryloxydipropoxyphenyl) fluorene, 9,9-bis (4-acryloxyethoxy-3-methylphenyl) fluorene, 9,9-bis (4-acryloxyethoxy-3)
-Ethylphenyl) fluorene, 9,9-bis (4-acryloxydiethoxy-3-ethylphenyl) fluorene, 9,9-bis (4-acryloxyethoxy-3,5-
Examples include dimethyl) fluorene and compounds in which the above “acryloxy” is changed to “methacryloxy”.

Photo-radical polymerization initiator system used in the present invention
(c) is an initiator that produces active radicals by the first exposure for hologram production, and the active radicals polymerize the radically polymerizable compound (b), which is one of the constituents of the present invention. Any system will do. Examples of such a radical photopolymerization initiator system (c) include, for example, US Pat.
No. 66,055, No. 4,868,092, No. 4,96
5,171, JP-A-54-151024, and JP-A-5-151024.
No. 8-15,503, No. 58-29,803,
59-189,340, 60-76735, JP-A-1-28715, and Japanese Patent Application No. 3-556.
No. 9 and "Proceedings of Conference on Radiation Curing Asia"
(PROCEEDINGS OF CONFERENC
E ON RADIATION CURING ASI
A) "(P.461-477, 1988) and the like, but known initiator systems can be used.

In the present specification, the term "initiator system" means that a sensitizer, which is a component that generally absorbs light, and an active radical generating compound or an acid generating compound can be used in combination. As the sensitizer in the photo-radical polymerization initiator system, a colored compound such as a dye is often used in order to absorb visible laser light, but when the final hologram is required to be colorless and transparent (for example, in an automobile, (When used as a head-up display of the above), as a sensitizer, JP-A-58-29803, JP-A 1-2
It is preferable to use cyanine dyes as described in Japanese Patent Application No. 87105 and Japanese Patent Application No. 3-5569.

Since the cyanine dyes are generally easily decomposed by light, the dyes in the hologram are decomposed in the visible region by post-exposure according to the present invention or by leaving it for several hours to several days under room light or sunlight. A colorless and transparent hologram is obtained without absorption. Specific examples of the cyanine dye include anhydro-3,3′-dicarboxymethyl-
9-ethyl-2,2'thiacarbocyanine betaine, anhydro-3-carboxymethyl-3 ', 9-diethyl-
2,2'thiacarbocyanine betaine, 3,3 ', 9-triethyl-2,2'-thiacarboxyanine iodine salt,
3,9-Diethyl-3'-carboxymethyl-2,2'-thiacarbocyanine iodine salt, 3,3 ', 9-triethyl-2,2'-(4,5,4 ', 5'-dibenzo ) Thiacarbocyanine iodine salt, 2- [3- (3-ethyl-2-benzothiazolidene) -1-propenyl] -6- [2- (3-ethyl-2-benzothiazolidene) ethylideneimino ] -3-Ethyl-1,3,5-thiadiazolium iodine salt, 2-
[[3-allyl-4-oxo-5- (3-n-propyl-
5,6-Dimethyl-2-benzothiazolilidene) -ethylidene-2-thiazolinylidene] methyl] 3-ethyl-4,
5-diphenylthiazolinium iodine salt, 1,1 ', 3,
3,3 ', 3'-hexamethyl-2,2'-indotricarbocyanine-iodine salt, 3,3'-diethyl-2,2'-thiatricarbocyanine perchlorate, anhydro-1-ethyl -4-Methoxy-3'-carboxymethyl-5'-chloro-2,2'-quinothiacyanine betaine, anhydro-5,5'-diphenyl-9-ethyl-3,3'-disulfopropyloxacarbocyanine Hydroxide triethylamine salt, 2- [3- (3-ethyl-2-benzothiazolidene) -1-propenyl] -6- [2- (3-ethyl-2)
-Benzothiazolidene) ethylideneimino] -3-ethyl-1,3,5-thiadiazolium iodine salt,
One or more of these may be used.

As the active radical generating compound which may be used in combination with the cyanine dye, the above-mentioned JP-A-58 is used.
-29803, JP-A-1-287105,
Diaryl iodonium salts as described in Japanese Patent Application No. 3-5569, or 2,4,6-substituted-1,3,
Examples include 5-triazines. The use of diaryliodonium salts is particularly preferred when high photosensitivity is required. Specific examples of the diaryliodonium salts include diphenyliodonium, 4,4′-dichlorodiphenyliodonium, 4,4′-dimethoxydiphenyliodonium, 4,4′-ditert-butyldiphenyliodonium and 3,3′-dinitrodiphenyliodonium. Chloride, bromide, tetrafluoroborate, etc.
Hexafluorophosphate, hexafluoroarsenate, hexafluoroantimonate, etc. are exemplified. Specific examples of 2,4,6-substituted-1,3,5-triazines include 2-methyl-4,6-bis (trichloromethyl) -1,3,5-triazine, 2,4,5. -Tris (trichloromethyl) -1,3,5-triazine, 2-phenyl-
4,6-bis (trichloromethyl) -1,3,5-triazine, 2,4-bis (trichloromethyl) -6- (p-methoxyphenylvinyl) -1,3,5-triazine, 2- (4 '
Examples include -methoxy-1'-naphthyl) -4,6-bis (trichloromethyl) -1,3,5-triazine.

The thermal latent cationic polymerization initiator system (d) used in the present invention is capable of initiating polymerization of the cationically polymerizable compound by generating an initiating species such as Bronsted acid or Lewis acid by the action of heat. It is not particularly limited as long as it is one, but it is preferable to use a cationic polymerization initiator system having the following thermal potential:

General formula,

Embedded image

[In the formula, each R ^c represents —COR ^a , —R ^b , which may be the same or different, an amino group which may be substituted with a hydroxy group, a cyano group or an alkyl group, and each R ^d
Represents H, -R ^a or a halogen atom, which may be the same or different, and A is

[0027]

[Chemical 4] Represents,

Each R ^e may be the same or different and is an alkyl group having 1 to 12 carbon atoms (these may form an aromatic ring with each other) or an alkenyl group (these are hydroxy,
It may be substituted with a carboxy, nitro, cyano, alkoxy having 1 to 4 carbons or an alkanoyloxy group. ) Or a phenyl group (which is a halogen atom, nitro,
Cyano, amino, -NR ^c, it may be substituted with -R ^a or -OR ^a group. ) Represents, R ^a represents an alkyl or cycloalkyl group having 1 to 4 carbon atoms which may be substituted with a hydroxy group, R ^b is H, -R ^a, -
Represents an OR ^a , a halogen atom or a nitro group, and X represents AsF.
₆ , SbF ₆ , BF ₄ , PF ₆ , ClO ₄ , FeCl ₄ , CF ₃ S
Represents O ₃ , R ^e SO ₃ or R ^e COO. ] The compound represented by

General formula,

Embedded image

[Wherein each R ^f represents H, —R ^a , an alkenyl group having 2 to 3 carbon atoms or —R ^i, which may be the same or different, and each R ^g may be the same or different. —R ^a represents an alkenyl group having 2 to 3 carbon atoms or —R ⁱ , and each R ^h may be the same or different, H, a hydroxy group, —R ^a , —O.
Represents R ^a or —R ⁱ , R ⁱ is a phenyl group (which is a halogen atom, hydroxy, nitro, cyano, —NHR ^a ,
It may be substituted with ^a -R ^a or -OR ^a group. ), M represents an integer of 1 to 4, and R ^a and X have the same meanings as described above. ] The compound represented by, and

General formula,

[Chemical 6]

[In the formula, R ^j may be the same or different and is an alkyl group having 1 to 20 carbon atoms (these may form a ring with each other) or an alkenyl group (these are hydroxy,
It may be substituted with carboxy, nitro, cyano, alkoxy having 1 to 4 carbon atoms or alkanoyloxy group. Or a phenyl group (which represents a halogen atom, nitro, cyano, an amino group which may be substituted by an alkyl group, or an R ^a or OR ^a group which may be substituted). To be

In the present specification, "heat potential" means
It is the property of exhibiting a function only when heated above a certain temperature.

Of these, the benzylammonium salt-based compound represented by the general formula [I] is particularly preferable for obtaining a hologram excellent in refractive index modulation, heat resistance and light resistance.

Specific examples include N-benzyl-N, N-dimethylanilinium, N- (p-methoxybenzyl) -N, N-dimethylanilinium and N- (p
-Methylbenzyl) -N, N-dimethylanilinium, N
-(P-t-butylbenzyl) -N, N-dimethylanilinium, N- (p-chlorobenzyl) -N, N-dimethylanilinium, N- (p-nitrobenzyl) -N, N-dimethylanili N, N-benzyl-N, N-dimethyl-N-
(p-tolyl) ammonium, 1-benzyl-2-chloropyridinium, 1- (p-methoxybenzyl) -2-chloropyridinium, 1- (p-phenylbenzyl) -2-methylpyridinium, 1- (p-methoxy Benzyl) -2-
Examples thereof include cyanopyridinium, and examples of these anion moieties include SbF ₆ ⁻ , PF ₆ ⁻ , BF ₄ ⁻ , CF ₃ SO ₃ ⁻ , C
H ₃ SO ₃ ⁻ , HSO ₃ ^{− and the} like can be mentioned.

Further, when the stability of the composition during storage is taken into consideration, it is preferable to use a cationic polymerization initiator system having a thermal potential of not reacting below 70 ° C.

In the present invention, in addition to the above-mentioned cationic polymerization initiator system (d) having thermal potential, a photocationic polymerization initiation system is used.
(e) can also be used. The cationic photopolymerization initiator system (e) used in the present invention has a low photosensitivity to the first exposure and is exposed to a light having a wavelength different from that of the first exposure to be exposed to the Bronsted acid or , Lewis acid is generated, it may be an initiator system such that these polymerize the cationically polymerizable compound (a), but in the present invention,
During polymerization of the radically polymerizable compound by irradiation with laser light or light having excellent coherence, it is preferable that the cationically polymerizable compound in a liquid state at room temperature be present almost unreacted, which results in a larger refractive index modulation than that of the prior art. It is thought to be obtained. Therefore, it is particularly preferable that the cationic photopolymerization initiator system does not polymerize the cationically polymerizable compound during the first exposure.

Examples of the cationic photopolymerization initiator system (e) include "UV curing; science and technology (UV CURING: SCI).
ENCE AND TECHNOLOGY) "(pp.23
~ 76, S. Peter Purpose (S. PETER P
APPAS) Editing, A Technology Marketing Publication (A TECHNOLOGY M
ARKETING PUBLICATION]] and “Comments Inorg.
m. ) "(B. Klingert, M. Leediker and A.
Rolov (B.Klingert, M.RIEDIKER
and A. ROLOFF), Volume 7, No. 3, pp10
9-138 (1988)] and the like, and one or more of them may be used.

Particularly preferred cationic photopolymerization initiator system (e) used in the present invention includes diaryl iodonium salts, triaryl sulfonium salts, iron allene complexes and the like.

Preferred examples of the diaryl iodonium salts as the photocationic polymerization initiator system (e) include the tetrafluoroborate, hexafluorophosphate, hexafluoroarsenate of iodonium represented by the photoradical polymerization initiator (c), and Hexafluoroantimonate, trifluoromethanesulfonate, 9,10
-Dimethoxyanthracene sulfonate and the like. Preferred triarylsulfonium salts are triphenylsulfonium, 4-tert-butyltriphenylsulfonium, tris (4-methylphenyl) sulfonium, tris (4-methoxyphenyl).
Sulfonium, tetrafluoroborate of sulfonium such as 4-thiophenyltriphenylsulfonium, hexafluorophosphate, hexafluoroarsenate and hexafluoroantimonate, trifluorosulfonate, 9,10-dimethoxyanthracene-2
-Sulfonates and the like.

In the photosensitive composition of the present invention, if necessary, a polymer binder, a thermal polymerization inhibitor, a silane coupling agent,
You may use a coloring agent, a ultraviolet absorber, etc. together. The polymer binder is used to improve the film-forming property and film thickness uniformity of the composition before hologram formation, and to post-expose the interference fringes formed by polymerization by irradiation with laser light or light with excellent coherence. It is used for stable existence until. The polymer binder may be one having good compatibility with the cationically polymerizable compound or the radically polymerizable composition, and specific examples thereof include chlorinated polyethylene, polymethylmethacrylate, methylmethacrylate and other (meth) acrylic acid. Examples thereof include copolymers of alkyl esters, copolymers of vinyl chloride and acrylonitrile, polyvinyl acetate, polyvinyl alcohol, polyvinyl formal, polyvinyl butyral, polyvinyl pyrrolidone, ethyl cellulose and acetyl cellulose. The polymer binder may have reactivity such as a cationically polymerizable group in its side chain or main chain.

When an ultraviolet absorber is used in a conventional system using a cationic photopolymerization initiator, polymerization inhibition occurs. However, in the thermal latent initiator system of the present invention,
Since such polymerization inhibition did not occur, it was possible to realize the combined use of an ultraviolet absorber. As the ultraviolet absorber, known ones which are usually used for improving weather resistance can be used,
Specifically, benzotriazole type, benzophenone type,
UV absorbers such as oxalic acid anilide-based, dicyanoacrylate-based, triazine-based, and benzoate-based UV absorbers can be used, but are not limited thereto. As a specific example, 2- (5
-Methyl-2-hydroxyphenyl) benzotriazole, 2- (3,5-t-butyl-2-hydroxyphenyl)
Benzotriazole, 2- [2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole, 2- [5- (2-octyloxycarbonylethyl) -3-t-butyl -2-hydroxyphenyl]
Benzotriazole, 2-hydroxy-4-n-dodecyloxybenzophenone, 2-hydroxy-4-methacryloxyethyloxybenzophenone, 2-ethoxy-
2'-dodecyloxy oxalic acid acid bisanilide, 2-ethoxy-5-t-butyl-2'-ethyl oxalic acid bisanilide, ethyl-2-cyano-3,3-diphenyl acrylate and the like can be mentioned. .
Of these, benzotriazole-based UV absorbers are particularly preferable in terms of light resistance and compatibility.

A light stabilizer may be used in combination with the ultraviolet absorber. Light stabilizers are generally radical scavengers or HALS (Hindered Amine Light Stabilizers).
It is known that a synergistic effect can be obtained by using it together with an ultraviolet absorber, and it can be optionally used in the present invention.

In the composition of the photosensitive composition of the present invention, the component (a) is contained in an amount of 5-80 wt% (particularly 30-%) based on the total weight of the composition.
60 wt%), component (b) is 10-80 wt% (especially 30-60w)
t%), the radical photopolymerization initiator system (c) is 0.3 to 8 wt% (particularly 1 to 5 wt%), and the cationic polymerization initiator system (d) having thermal potential is 0.3 to 8 wt% (particularly 1-5 wt%) is preferred.

The photosensitive composition of the present invention may be prepared by a conventional method. For example, the above-mentioned essential components (a) to (d) and optional components as they are or as necessary a solvent (e.g., methyl ethyl ketone, methyl isobutyl ketone, acetone,
Ketone solvents such as cyclohexanone, ethyl acetate, butyl acetate, ester solvents such as ethylene glycol diacetate, aromatic solvents such as toluene and xylene,
Cellosolve solvents such as methyl cellosolve, ethyl cellosolve, butyl cellosolve, methanol, ethanol,
Propanol, alcohol solvent such as n-butanol, tetrahydrofuran, ether solvent such as dioxane, halogen solvent such as dichloromethane, dichloroethane, chloroform) are blended and mixed by using, for example, a high-speed stirrer in a cool dark place. Can be prepared.

In the production of the hologram of the present invention, the recording layer is a transparent support such as a glass plate, a polyethylene terephthalate film, a polyethylene film, an acrylic plate, a triacetyl cellulose film or a polycarbonate plate, which is prepared by using the above-mentioned photosensitive composition in a usual manner. It can be formed by coating on the surface and drying if necessary. The coating amount is appropriately selected. For example, the dry coating amount is 1 g / m ²
It may be ˜50 g / m ² . Further, usually, a polyethylene terephthalate film, a polyethylene film, a polypropylene film, as a protective layer on the recording layer,
It is used by providing a triacetyl cellulose film, a polycarbonate plate, a glass plate, an acrylic plate or the like. As another method for producing a three-layer body in which the intermediate layer is the recording layer of the composition of the present invention, for example, recording is performed between two polyethylene terephthalate films, each of which has been subjected to a treatment for easy peeling. A layer may be formed in advance, and one film may be peeled off at the time of use and the surface thereof may be laminated on an appropriate support. Further, for example, the composition of the present invention can be injected between two glass plates.

The recording layer thus prepared was excellent in laser light and coherence (for example, wavelengths of 300 to 12).
The interference fringes are recorded therein by the exposure of the interference fringes by the usual holographic exposure device of (00 nm). At this stage, the unreacted polymerizable compound remains in the photosensitive layer. Therefore, in order to obtain optical performance that does not change with time, it is necessary to cure the unreacted polymerizable compound. For that purpose, it is necessary to heat above the temperature at which the cationic polymerization initiator system having thermal potential starts the reaction, following the above-mentioned interference fringe exposure. By this operation, the unreacted cationically polymerizable compound can be polymerized to fix the interference fringes. Polymerization of the radical-polymerizable compound occurs in the stage of the above-mentioned interference fringe exposure, but the unreacted radical-polymerizable compound may be present in the photosensitive layer in addition to the unreacted cationically-polymerizable compound. Therefore, in order to increase the polymerization rate of these unreacted polymerizable compounds, it is desirable that the above-mentioned interference fringe exposure be followed by overall exposure to ultraviolet and / or visible light and heat treatment simultaneously or sequentially. When a high-pressure mercury lamp, metal halide lamp or halogen lamp is used as the light source when exposing the entire surface, ultraviolet rays and /
Alternatively, heat rays are emitted along with light in the visible range. Therefore, by exposing the entire surface with these light sources under the condition that the photosensitive layer is heated above the reaction temperature of the cationic polymerization initiator system having thermal potential, it is economical because the exposure and the heat treatment can be carried out simultaneously. Furthermore, photocationic polymerization initiator system (e)
By compounding the compound in the photosensitive layer, it is possible to induce the polymerization of the cationically polymerizable compound during the entire surface exposure, so that the polymerization rate of the unreacted compound in the photosensitive layer can be further increased.

The above-mentioned volume hologram is, for example, a lens, a diffraction grating, an interference filter, a head-up display device, a general three-dimensional display, a coupler for an optical fiber, an optical polarizer for a facsimile, a memory material for an ID card or the like, an architectural material. It can be used for window glass, advertising media, etc.

[0049]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited thereto. Using the photosensitive compositions shown in each of Examples and Comparative Examples described below, a test plate was prepared by the following method, exposed to obtain each hologram, and the physical properties were evaluated by the following methods.

(Preparation of test plate) 1.2 g of n-butyl alcohol, 1.0 g of methyl isobutyl ketone, and a predetermined amount of photoradical polymerization initiator system components and cationic polymerization initiator system components were added.
After being dissolved or dispersed in a mixed solution of 0.2 g of toluene,
A predetermined amount of the cationically polymerizable compound, the radically polymerizable compound and the binder polymer were added, and the mixture was stirred and filtered to obtain a photosensitive solution. Use this applicator to apply this sensitizer 16
It was applied on a glass plate of cm × 16 cm and dried at 90 ° C. for 5 minutes. Furthermore, a polyethylene film of 80 μm thickness (LUPIC LI of Tonen Kagaku Co., Ltd.) was laminated on it using a laminating roller, and this plate was 3-4 cm.
The test plate was divided into corners.

(Exposure) The first exposure was performed with an argon laser 51.
It was performed using 4.5 nm light. FIG. 1 shows a schematic diagram of a recording method of a reflection hologram. The light intensity of one light flux on the surface of the test plate was 1 mW / cm ² , and the exposure was performed for 30 seconds. Post-heating or post-exposure conditions after the completion of the first exposure will be shown in Examples described later.

(Evaluation) The diffraction efficiency of the reflection hologram is
It was determined from the reflectance of the hologram by Shimadzu's own recording spectrophotometer UV-2100 and the attached integrating sphere device ISR-260.
In addition, the film thickness of the diffraction efficiency measurement portion was measured using a film thickness measuring instrument Betascope 850 manufactured by Fisher. The refractive index modulation (half the change in the refractive index of the interference fringes) was calculated and calculated from the thus obtained values of the diffraction efficiency and the film thickness. The calculation formula is "Coupled Wave Theory for Thick Hologram Gratings" (Coupled
Wave Theory for Thick Hologram Glating
s) (H. Kogelnik, Bell Syst Tech. J., Vol. 48, Vol. 2)
What was described in pages 909-2947 (1969)) was used. The refractive index modulation value does not depend on the film thickness, and the refractive index modulation ability of the composition can be compared by this value.

Regarding the heat resistance test, changes in the diffraction efficiency and changes in the diffraction peak wavelength were examined after the hologram test plate was left in a Flanker at 100 ° C. for 1000 hours.

Regarding the light resistance, Dainippon Plastic Co., Ltd.
Using a super accelerated weather resistance tester W type, Super UV Tester, the hologram test plate has wavelengths from 295 nm to 4
The change in the diffraction efficiency of the hologram test plate, the change in the diffraction peak wavelength, and the color difference were investigated when the sample was continuously irradiated with 50 nm ultraviolet light for 60 hours.

The color difference was measured by a transmission measurement method based on JIS-K7103 using a color computer SM4-CH type manufactured by Suga Test Instruments Co., Ltd.

The photosensitive compositions of the following Examples and Comparative Examples were prepared, and each hologram was prepared by the above method, and evaluated as described above.

(Examples 1 to 3) In this example, reflection holograms were prepared using various thermal latent cationic polymerization initiator systems (d). However, 514.5 for all first exposures
at 30 nm for 30 seconds, then exposed to light from a 15 W low-pressure mercury lamp for 1 minute from the polyethylene film side, and 120 ° C.
And heated for 5 minutes to create a hologram. Almost no heating of the test plate due to exposure to the low-pressure mercury lamp occurred. In addition,
CAT-1 as the cationically polymerizable compound (a), A-BPHE as the radically polymerizable compound (b), DYE-1 and DPI.CF ₃ S as the photoradical polymerizable initiator system (c).
The combination of O ₃ was used.

Table 1 shows the composition and amount of the hologram recording photosensitive compositions used in Examples 1 to 3.

Table 2 shows the hologram evaluation results and the heat resistance test results.

[0060]

[Table 1]

[0061]

[Table 2]

In each of the examples, a reflection hologram with high diffraction efficiency and high refractive index modulation was obtained. In addition, the diffraction peak wavelength of the hologram hardly changed after the heat resistance test.

(Comparative Example 1) This is a comparative example to Examples 1 to 3, except that TPS.SbF ₆ which is a photocationic polymerization initiator is used instead of the thermal latent cationic polymerization initiator system. A hologram was created in the same manner as in Examples 1 to 3.

Table 3 shows the composition and amount of the hologram recording photosensitive composition used.

Table 4 shows the hologram evaluation results and the heat resistance test results. After the heat resistance test, the diffraction peak wavelength of the hologram was greatly shifted by a short wavelength.

[0066]

[Table 3]

[0067]

[Table 4]

(Examples 4 to 6) In this example, the composition of Table 1 was used, the first exposure was performed at 514.5 nm for 30 seconds, and then the mixture was heated at 120 ° C. for 5 minutes, and further, polyethylene was applied using a low pressure mercury lamp. An example in which a hologram was created by exposing the film side for 1 minute is shown. (The compositions of Examples 4, 5, and 6 are the same as those of Examples 1, 2, and 3 in Table 1, respectively)

Table 5 shows the hologram evaluation results and the heat resistance test results.

[0070]

[Table 5]

In each of the examples, a reflection hologram having high diffraction efficiency and high refractive index modulation was obtained. In addition, the diffraction peak wavelength of the hologram changed only after the heat resistance test.

(Comparative Example 2) This is a comparative example to Examples 4 to ₆ , except that TPS.SbF6, which is a photocationic polymerization initiator, is used in place of the heat-latent cationically polymerizable initiator system. Holograms were prepared in the same manner as in Examples 4-6. (Composition is the same as Comparative Example 1 in Table 4)

The obtained hologram had a low diffraction efficiency of 55% and the reproduction wavelength peak was split into a plurality of peaks.

(Examples 7 to 9) Here, the compositions of Table 1 were used, the first exposure was performed at 514.5 nm for 30 seconds, and then a high pressure mercury lamp (manufactured by Nippon Batteries Co., Ltd., an experimental ultraviolet irradiation device) was used. , FL-1001-2) was used to expose a polyethylene film for 1 minute to form a hologram. It should be noted that the test plate was irradiated with the light of the high pressure mercury lamp to 115
The temperature was raised to ° C. (The compositions of Examples 7, 8 and 9 are the same as those of Examples 1, 2 and 3 in Table 1, respectively)

Table 6 shows the hologram evaluation results and the heat resistance test results.

[0076]

[Table 6]

In each of the examples, a reflection hologram having high diffraction efficiency and high refractive index modulation was obtained. In addition, the diffraction peak wavelength of the hologram hardly changed after the heat resistance test.

(Comparative Example 3) This is a comparative example to Examples 7 to 9 except that TPS · SbF ₆ which is a photocationic polymerization initiator is used instead of the thermal latent cationic polymerization initiator system. Holograms were prepared in the same manner as in Examples 7-9. (Composition is the same as Comparative Example 1 in Table 4)

Table 7 shows the hologram evaluation results and the heat resistance test results. After the heat resistance test, the diffraction peak wavelength of the hologram was greatly shifted by a short wavelength.

[0080]

[Table 7]

Examples 10-12 Here, the compositions of Table 1 are used, the first exposure is carried out at 514.5 nm for 30 seconds and then a high-pressure mercury lamp (same as used in Examples 7-9). An example is shown in which a hologram was prepared by exposing the film from the polyethylene film side for 1 minute using, and heating at 120 ° C. for 5 minutes. The test plate was heated to 115 ° C. by irradiation with light from a high pressure mercury lamp. (Examples 10, 11, 12
(The composition of each is the same as in Examples 1, 2, and 3 of Table 1)

Table 8 shows the hologram evaluation results and the heat resistance test results.

[0083]

[Table 8]

In each of the examples, a reflection hologram having high diffraction efficiency and high refractive index modulation was obtained. In addition, the diffraction peak wavelength of the hologram hardly changed after the heat resistance test.

(Comparative Example 4) This is a comparative example to Examples 10 to 12, and all except that the photo-cationic polymerization initiator TPS · SbF ₆ was used in place of the thermal latent cationic polymerization initiator system. Holograms were prepared in the same manner as in Examples 10-12. (Composition is the same as Comparative Example 1 in Table 4)

Table 9 shows the hologram evaluation results and the heat resistance test results. After the heat resistance test, the diffraction peak wavelength of the hologram was greatly shifted by a short wavelength.

[0087]

[Table 9]

Example 13 In this example, the composition of Example 1 is further supplemented with TPS.SbF which is a photocationic polymerization initiator.
Examples 10 to 12 were prepared using a composition containing 80 mg of ₆ added.
An example in which a hologram is created in the same process as the above is shown.

Table 10 shows the hologram evaluation results and the heat resistance test results. A reflection hologram with high diffraction efficiency and high refractive index modulation was obtained. In addition, the diffraction peak wavelength of the hologram hardly changed after the heat resistance test.

[0090]

[Table 10]

Example 14 In this example, the composition of Example 1 is used, and the first exposure is performed at 514.5 nm for 30 seconds, and then heated at 120 ° C. for 5 minutes to form a hologram.

Table 11 shows the hologram evaluation results and the heat resistance test results. A reflection hologram with high diffraction efficiency and high refractive index modulation was obtained. In addition, the diffraction peak wavelength of the hologram hardly changed after the heat resistance test.

[0093]

[Table 11]

(Comparative Example 5) This is a comparative example to Example 14, except that the photo-cationic polymerization initiator TPS · SbF ₆ was used in place of the thermal latent cationic polymerization initiator system. A hologram was prepared in the same manner as 14. (Composition is the same as Comparative Example 1 in Table 4)

The obtained hologram had a low diffraction efficiency of 50%, and the reproduction wavelength peak was divided into a plurality of peaks. The heat resistance test could not be performed because the curing of the photosensitive layer was insufficient and the polyethylene film could not be peeled off.

(Examples 15 to 17, Comparative Example 6) Here,
An example is shown in which a hologram was prepared using the photosensitive composition containing an ultraviolet absorber in the same steps as in Examples 10 to 12, and the performance evaluation and the light resistance test were performed. For comparison, a composition using only a photocationic polymerization initiator (TPS / SbF ₆ ) without using a cationic polymerization initiator system having thermal potential (Comparative Example 6)
Was also conducted.

Table 12 shows the compositions of the hologram recording photosensitive compositions of Examples 15 to 17 and Comparative Example 6, the evaluation results of the holograms, and the results of the light resistance test. The smaller the numerical value of the color difference (ΔE Lab) in Table 12, the smaller the color change.

[0098]

[Table 12]

In all of the examples, holograms having excellent light resistance and high diffraction efficiency were obtained, but in Comparative Example 6 in which the photolatent cationic polymerization initiator was used without using the thermal latent cationic polymerization initiator, the The absorber inhibits the action of the photocationic polymerization initiator, resulting in the splitting of the diffraction peak into two parts. Furthermore, the decrease in the diffraction efficiency of the hologram after the light resistance test and the short wavelength shift of the diffraction wavelength are large, and A change of layers was seen.

The above Examples 1 to 17 and Comparative Examples 1 to 6,
The abbreviations of the compounds shown in Tables 1 to 12 are as follows.

Thermally Latent Cationic Polymerization Initiator System BA-1 ... N- (p-methoxybenzyl) -N, N-
Dimethylanilinium hexafluoroantimonate-BA-2 ... 1- (p-methoxybenzyl) -2-chloropyridinium hexafluoroantimonate-BA-3 ... N- (p-methoxybenzyl) -N, N −
Dimethylanilinium trifluoromethyl sulfonate

Radical Polymerizable Compound A-BPHE ... 9,9-bis (3-ethyl-4-acryloxydiethoxyphenyl) fluorene

Cationic Polymerizable Compound CAT-1 ... Glycidyl ether obtained by adding 4 moles of propylene oxide to pentaerythritol (the number of glycidyl groups per molecule is 3.).

[0104] photoradical polymerization initiator · DYE-1 ··· 3,9- diethyl-3'-carboxymethyl-2,2'-thiacarbocyanine iodine salt · DPI · CF ₃ SO ₃ ··· diphenyliodonium・
Trifluoromethanesulfonate

[0105] cationic photopolymerizable initiator system, TPS, SbF ₆ · · · manufactured by Ciba-Geigy, triarylsulfonium, hexafluoroantimonate compound, trade name UV16974

UV absorber-UVA-1 ... 2- [5- (2-octyloxycarbonylethyl) -3-t-butyl-2-hydroxyphenyl] benzotriazole (TINUVIN384 manufactured by Ciba-Geigy) -UVA- 2 ... Benzotriazole type ultraviolet absorber (TINUVIN1130, manufactured by Ciba-Geigy)

Other components P-1 ... Methyl methacrylate ethyl acrylate glycidyl methacrylate copolymer (preparation ratio = 1
1/79/10) ・ MIBK ・ ・ ・ Methyl isobutyl ketone ・ BuOH ・ ・ ・ n-Butyl alcohol ・ TL ・ ・ ・ Toluene

[Brief description of drawings]

FIG. 1 shows a schematic view of a reflection hologram recording method in the first exposure.

[Explanation of symbols]

 1: Glass plate 2: Recording layer 3: Polyethylene film 4: Laser 5: Laser beam 6: Mirror 7: Beam splitter 8: Objective lens 9: Lens

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Internal reference number FI Technical display location G03F 7/20 505 G03H 1/02 1/04 (72) Inventor Sumiyoshi Iwao Ikedanaka-cho, Neyagawa-shi, Osaka 19th-17th Japan Paint Co., Ltd.

Claims (12)

[Claims] 1. A photosensitive composition for volume hologram recording, which is used for recording interference fringes produced by interference of laser light or light having excellent coherence as fringes having different refractive indexes, the composition comprising: , (A) a cationically polymerizable compound which is liquid at room temperature, (b) a radically polymerizable compound, (c)
A photoradical polymerization initiator system for polymerizing the component (b) by being exposed to the above laser beam or light having excellent coherence.
And (d) each component of a cationic polymerization initiator system having thermal latent property, which is a photosensitive composition for volume hologram recording. 2. The composition according to claim 1, wherein the component (d) is a benzyl ammonium salt compound. 3. The composition according to claim 1, wherein the component (d) does not initiate polymerization when the temperature is lower than 70 ° C., and exhibits cationic polymerization initiation ability when heated at the same temperature or higher. 4. A composition according to claim 1, wherein the average refractive index of component (a) is lower than that of component (b). 5. A cationic photopolymerization initiator system which has a low photosensitivity to the laser light or the light excellent in coherence and which is capable of polymerizing the component (a) by being exposed to light of another wavelength.
The composition according to claim 1, further comprising (e). 6. The composition according to claim 1, further comprising an ultraviolet absorber. 7. The method of claim 1, further comprising a polymeric binder.
The composition as described. 8. A volume hologram recording medium having a recording layer comprising the composition of claim 1 between two transparent supports, which may be the same or different. 9. A volume hologram recording method, wherein the recording medium of claim 8 is exposed to interference fringes generated by interference of laser light or light having excellent coherence, and then the recording medium is heat-treated. 10. The recording medium according to claim 8 is exposed to interference fringes generated by interference of laser light or light having excellent coherence, and then the entire surface of the recording medium is exposed to light in the ultraviolet and / or visible region. A method for recording a volume hologram in which heat treatment is performed simultaneously or sequentially. 11. The recording method according to claim 10, wherein the heat treatment is performed by utilizing heat generated in the entire surface exposure step of light in the ultraviolet and / or visible region. 12. A hologram formed by the method according to claim 9.