JPH09179479A - Manufacture of hologram - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control method for the reproduced wavelength by film thickness shrinkage and manufacture new hologram. SOLUTION: An interference film generated by the interference of a laser beam or the light excellent in coherence property is recorded as fringes having different refraction factors to manufacture hologram. The laser beam for forming the hologram is exposed on the film of a photosensitive composition containing a radical polymerization monomer, a cation polymerization monomer, a light radical polimerization initiator, a light cation polimerization initiator, and an organic solvent. Ultraviolet rays are radiated to the whole film, then the film is heated at 100-180 deg.C for 1-120min to evaporate the volatile component of the organic solvent. The hologram can be manufactured when the reproduced wavelength is controlled to be made smaller than the recorded wavelength by film thickness shrinkage.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a hologram, for example, a reflection hologram used for a head-up display or the like.

[0002]

2. Description of the Related Art FIG. 3 schematically shows a head-up display. A combiner 11, a hologram optical element 12 for projecting a display image on the combiner, and a display unit 13 are provided on or near the windshield. The present apparatus allows the hologram optical element 12 to reflect a part of the emission spectrum from the display unit 13 and to perform an operation of enlarging or reducing an image, for example, to form a speed display image at an arbitrary position.

The color of the displayed image, that is, the reproduction wavelength of the hologram needs to be adjusted to a highly sensitive wavelength range because human eyes have different sensitivities depending on the wavelength, or it is necessary to adjust the hue to be different depending on the displayed contents. It is done.

However, when the holograms have the same optical arrangement during recording and reproduction, the laser light wavelength and the reproduction wavelength during hologram recording are the same. Here, there are various types of lasers used for recording holograms, and dye lasers have a large degree of freedom in oscillation wavelength and can meet various reproduction wavelength required values, but they are stable and cost-effective for industrial use. It is disadvantageous in terms. Therefore, ion lasers such as argon and krypton are used. However, these lasers have a problem that they cannot precisely meet the above-mentioned requirements for the reproduction wavelength because their oscillation wavelengths are discontinuous. Therefore, some countermeasures are taken.

First, since the incident angle of the recording light and the incident angle of the reproducing light have the relationship shown by the following equation, the reproducing wavelength can be changed by changing the incident angle of the reproducing light.

[Equation 1] (Where λ is the recording wavelength, λ'is the reproducing wavelength, θ is the recording crossing angle, and θ'is the reproducing crossing angle.) However, at this time, an aberration occurs in the reproduced image and the image distortion occurs. Occurs.

Therefore, a method of changing the reproduction wavelength satisfying the Bragg condition by changing the hologram film thickness after recording and changing the interference fringe spacing is adopted. This method is suitable for holograms such as head-up displays because it has few problems as described above. At this time, between the recording wavelength and the reproducing wavelength, λ ′ = Mz · λ (where λ ′ is the reproducing wavelength, λ is the recording wavelength, and Mz is the film thickness change rate = (film thickness during reproduction) / (recording time). Film thickness))).

As a method of controlling the reproduction wavelength by changing the film thickness,
There are longer wavelengths due to film thickness swelling and shorter wavelengths due to film thickness contraction. As a film thickness swelling method, there is a method of impregnating and fixing an organic solvent such as acetone, water, or a compound such as methyl methacrylate into a hologram film after recording, but there is a problem in reproducibility and stability. . Also, the film thickness shrinkage is
The DCG (dichromate gelatin) material could be adjusted by adjusting the amount of water, but it could not be applied to other materials.

JP-A-5-181271 discloses a photosensitive recording medium comprising a radical-polymerizable monomer, a cationic-polymerizable monomer, a radical-polymerizable monomer, a radical-polymerization initiator system and a composition containing the cationic-polymerization initiator system. On the other hand, the first exposure for hologram formation, the second exposure for irradiating the entire surface, and the subsequent heating for 30 to 120 minutes at 50 to 150 ° C. to further increase the refractive index modulation are described. However, in the heating step, at least one of a polymerization initiator system capable of evaporating a photodegradation product and an organic solvent capable of evaporating in the heating step is contained in the photosensitive recording medium in advance, and the heating step There is no disclosure of controlling the reproduction wavelength by evaporating these to cause film shrinkage.

[0009]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a novel hologram production method which can be produced by using a wide variety of materials as a method of controlling the reproduction wavelength by film thickness shrinkage.

[0010]

According to a first aspect of the present invention, there is provided:
In a method for producing a hologram in which interference fringes generated by interference of laser light or light having excellent coherence are recorded as fringes having different refractive indices, (a) a radical-polymerizable monomer, (b) a cation-polymerizable monomer, (c) ) A photo-radical polymerization initiator system that polymerizes the radical-polymerizable monomer by being exposed to the laser light or light having excellent coherence, and (d) is exposed to ultraviolet light having a wavelength different from the wavelength of the light of (c). A cationic photopolymerization initiator system that polymerizes the cationically polymerizable monomer and forms an evaporative decomposition product that evaporates by heating after being irradiated with ultraviolet rays.
A photosensitive composition containing is applied to a substrate to form a film, and the film is subjected to a first exposure with the laser light for forming a hologram or light having excellent coherence, and then the entire surface of the film is exposed. The second exposure is performed by irradiating ultraviolet rays having a wavelength different from the wavelength of the light used for the first exposure, and
It is the said manufacturing method characterized by heating the said film | membrane for 1 to 120 minutes at -180 degreeC, and making the said evaporative decomposition product evaporate.

A second aspect of the present invention is a method for producing a hologram in which interference fringes produced by interference of laser light or light having excellent coherence are recorded as fringes having different refractive indices. Monomer, (b)
A cationically polymerizable monomer, (c) a photo-radical polymerization initiator system which polymerizes the radically polymerizable monomer by being exposed to the laser beam or light having excellent coherence, (d)
(C) a cationic photopolymerization initiator system that is exposed to ultraviolet light having a wavelength different from the wavelength of light to polymerize the cationically polymerizable monomer, and (e) dissolves or disperses (a) to (d) above. First, a photosensitive composition containing a solvent that evaporates at 100 to 180 ° C. is applied to a substrate to form a film, and the film is subjected to the first exposure with the laser light or light having excellent coherence for forming a hologram. Then, second exposure is performed by irradiating the entire surface of the film with an ultraviolet ray having a wavelength different from the wavelength of the light used for the first exposure, and heat-drying the film at 100 to 180 ° C. for 1 to 120 minutes. Then, when the initiator system produces an evaporative product by the irradiation of the solvent and the ultraviolet ray, the evaporative product is vaporized.

A third aspect of the present invention is (a) a radically polymerizable monomer, (b) a cationically polymerizable monomer, and (c).
A photo-radical polymerization initiator system for polymerizing the radical-polymerizable monomer by being exposed to the laser beam or light having excellent coherence, and (d) (c) being exposed to an ultraviolet ray having a wavelength different from that of the light. A photosensitive composition containing a cationic photopolymerization initiator system that polymerizes the cationically polymerizable monomer and forms an evaporative decomposition product that evaporates by heating after being irradiated with ultraviolet light, is applied to a substrate to form a film,
This film is first exposed to the laser light for forming a hologram or light having excellent coherence, and then the entire surface of the film is exposed to ultraviolet rays having a wavelength different from the wavelength of the light used for the first exposure. A second exposure is carried out to heat the film to evaporate the volatile decomposition products to obtain a hologram, and a hologram is used to obtain a reproduction wavelength which is lower than the recording wavelength by 10 to 100 nm. .

A fourth aspect of the present invention is (a) a radically polymerizable monomer, (b) a cationically polymerizable monomer, and (c).
A photo-radical polymerization initiator system that polymerizes the radical-polymerizable monomer by being exposed to the laser light or light having excellent coherence, and being exposed to ultraviolet light having a wavelength different from the wavelengths of the light of (d) and (c). A photocationic polymerization initiator system for polymerizing a cationically polymerizable monomer, and (e) the above (a) to
A photosensitive composition containing a solvent that dissolves or disperses (d) and evaporates at 100 to 180 ° C. is applied to a substrate to form a film, and the film is provided with the laser beam or coherence property for forming a hologram. The first exposure is performed with excellent light, and then the second exposure is performed by irradiating the entire surface of the film with ultraviolet light having a wavelength different from the wavelength of the light to evaporate the evaporative component present in the composition. By this, a hologram is obtained, and with this hologram, the recording wavelength is 10 to 10
This is a method of obtaining a reproduction wavelength as low as 0 nm.

In the third and fourth aspects, it is preferable that in the evaporation step, the film is heated at 100 to 180 ° C. for 1 to 120 minutes. In the third and fourth aspects, the evaporative component is usually at least one of unreacted monomer, solvent and decomposition products of the initiator system. In the third and fourth aspects, the photosensitive composition may further contain a sensitizer.

The radical-polymerizable monomer that can be used in the first to fourth aspects of the present invention is either monofunctional or polyfunctional as long as it has an ethylenically unsaturated double bond in its molecular structure. Even one can be used. The form may be liquid or solid.
Specific examples thereof include acrylamide, methacrylamide, styrene, 2-bromostyrene, phenyl acrylate, 2-phenoxyethyl acrylate, 2,
3-naphthalenedicarboxylic acid (acryloxyethyl) monoester, methylphenoxyethyl acrylate, nonylphenoxyethyl acrylate, β-acryloxyethyl hydrogen phthalate, phenoxypolyethylene glycol acrylate, 2,4,6-tribromophenyl 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 ]]
Dibromodecylthio) ethyl acrylate, S- (1-
Naphthylmethyl) thioacrylate, dicyclopentanyl acrylate, methylenebisacrylamide, polyethylene glycol diacrylate, trimethylolpropane 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-acryloxy) Ethyl) (3-acryloxypropyl-2-hydroxy) diester, dibromoneopentyl glycol diacrylate, dipentaerythritol hexaacrylate, 1,3-bis [2-acryloxy-3- (2,4,6-tribromo) Phenoxy) propoxy] benzene, diethylenedithioglycol diacrylate, 2,2-bis (4-acryloxyethoxyphenyl) propane, bis (4-acryloxydiethoxyphenyl) methane, bis (4-acryloxyethoxy-3,
5-dibromophenyl) 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-acryloxy) Propoxyphenyl) sulfone, bis (4-acryloxyethoxy-3,5-dibromophenyl) sulfone, and compounds in which the above-mentioned acrylate is changed to methacrylate, and further JP-A-2-247205 and JP-A-2-261808. And an ethylenically unsaturated double bond-containing compound containing at least two S atoms in the molecule.

As the radical-polymerizable monomer that can be used in the first to fourth aspects of the present invention, there is a radical-polymerizable compound that has a 9,9-diarylfluorene skeleton and is liquid at room temperature. Is given by the following equation.

[0017]

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Here, R ¹ and R ² have a radically polymerizable group such as an acryloyl group or a methacryloyl group at at least one of the terminals, and this group and the benzene ring have at least one oxyethylene chain or oxy ring. It is bonded via a propylene chain, a urethane bond, an amide bond, or the like. Specific examples of X ^{1 to} X ⁴ : H, alkyl group (C _{1 to} C 4
₄ ), an alkoxy group (C _{1 to} C ₄ ), an amino group, a dialkylamino group, a hydroxyl group, a carboxyl group, a halogen group and the like.

Of 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-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-dimethyl) fluorene and the above "acryloxy" to "methacryloxy" Some compounds have been changed.

One or more of the above radically polymerizable monomers may be used.

The cationically polymerizable monomer used in the first to fourth aspects of the present invention is obtained by polymerizing the above radically polymerizable monomer by irradiation with laser light or light having excellent coherence (first exposure), Then, the whole surface exposure (second exposure) is performed to perform cationic polymerization with the Bronsted acid or Lewis acid generated by the decomposition of the cationic polymerization initiator system (d) in the composition. As the cationically polymerizable monomer, even if the photosensitive recording medium does not contain a solvent (first embodiment), the radically polymerizable monomer is liquid at room temperature so that the polymerization is always performed in a composition having a relatively low viscosity. It is preferable to use one of the following. Examples of such a cationically polymerizable monomer include, for example, “Chemtech. Oct.” [JV Clivero (J.
V. Crivello), page 624, (1980)], JP-A-6
No. 2-149784, Journal of Japan Adhesion Society [Vol. 26,
No. 5, pp. 179-187 (1990)] and the like.

Specific examples of the cationically polymerizable monomer include diglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, 1,4-bis (2,3-epoxypropoxyperfluoroisopropyl) cyclohexane, sorbitol polyglycidyl ether, trimethylol. Propane polyglycidyl ether, resorcin diglycidyl ether, 1,6-hexanediol diglycidyl ether, polyethylene glycol diglycidyl ether, phenyl glycidyl ether, paratertiary butyl phenyl glycidyl ether, adipic acid diglycidyl ester, orthophthalic acid diglycidyl ester, Dibromophenyl glycidyl ether, dibromo neopentyl glycol diglycidyl ether, 1, 2, 7, - 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 ,
Examples thereof include vinyl-n-butyl ether, triethylene glycol divinyl ether, 1,4-cyclohexanedimethanol divinyl ether, trimethylolethane trivinyl ether, vinyl glycidyl ether, and compounds represented by the following formula, and one or more of them are used. You can do it.

[0023]

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The photoradical polymerization initiator system (c) used in the first to fourth aspects of the present invention produces active radicals by the first exposure for hologram production, and the active radicals of the present invention are used. Any initiator system capable of polymerizing the radically polymerizable monomer, which is one of the constituent components, may be used. Examples of such a radical photopolymerization initiator system include, for example, U.S. Pat. Nos. 4,766,055 and 4,868,
092, 4,965,171, JP-A-54-1.
No. 51024, No. 58-15503, No. 58
No. 29803, No. 59-189340, No. 60-76735, No. 1-287715, No. 4-239505 and “Proceedings of Conference on Radiation Curing”.・ Asia "(PROCEEDINGS OF CONFERE
NCE ON RADIATION CURING ASIA) "(P.461-47)
Known initiator systems described in, for example, No. 7, 1988) can be used, but are not limited thereto.

In the first to fourth aspects of the present invention, the term "initiator system" means an active radical generating compound or an acid generating compound which is generally used in combination with a sensitizer which is a light absorbing component. I mean. As the sensitizer in the 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, automobiles, etc. Examples of sensitizers (when used as a head-up display), JP-A-58-29803, JP-A-1-287105, and Japanese Patent Application No. 3-55.
It is preferable to use a cyanine dye as described in JP-A-69. Since the cyanine dye is generally easily decomposed by light, the dye in the hologram is decomposed and absorbed in the visible region by the second exposure in the present invention or by leaving it for several hours to several days under room light or sunlight. , And a colorless and transparent hologram is obtained. Specific examples of cyanine dyes include anhydro-3,3'-dicarboxymethyl-9-ethyl-2,2'thiacarbocyanine betaine and anhydro-3-carboxymethyl-3 ', 9.
-Diethyl-2,2'thiacarbocyanine betaine,
3,3 ', 9-triethyl-2,2'-thiacarbocyanine 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 iodide, 2-
[[3-allyl-4-oxo-5- (3-n-propyl-5,6-dimethyl-2-benzothiazolilidene) -ethylidene-2-thiazolinylidene] methyl] 3-ethyl-4,5-diphenyl Thiazolinium / 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 salts are mentioned.
More than one species may be used.

As the active radical generating compound which may be used in combination with the cyanine dye in the radical polymerization initiator system, the above-mentioned JP-A-58-29803, JP-A-1-287105 and JP-A-4-239505 are available.
Examples thereof include diaryliodonium salts as described in JP-A No. 1994-242, and 2,4,6-substituted-1,3,5-triazines. The use of diaryliodonium salts is particularly preferred when high photosensitivity is required. Specific examples of the above-mentioned diaryliodonium salts include diphenyliodonium, 4,4'-dichlorodiphenyliodonium, 4,4'-dimethoxydiphenyliodonium, 4,4'-ditertiarybutyldiphenyliodonium and 3,3'-dinitrodiphenyliodonium. Examples thereof include chloride, bromide, tetrafluoroborate, hexafluorophosphate, hexafluoroarsenate, hexafluoroantimonate, trifluoromethanesulfonate and the like. Specific examples of the 2,4,6-substituted-1,3,5-triazines include 2-methyl-4,6-bis (trichloromethyl) -1,3,5.
-Triazine, 2,4,6-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
Examples include-(4'-methoxy-1'-naphthyl) -4,6-bis (trichloromethyl) -1,3,5-triazine.

The photocationic polymerization initiator system (d) used in the first to fourth aspects of the present invention has a low photosensitivity to the first exposure and emits an ultraviolet ray having a wavelength different from that of the first exposure. Any initiator system may be used which is capable of generating a Bronsted acid or a Lewis acid by being exposed to the second exposure light for irradiation and polymerizing the above cationically polymerizable compound. Examples of such a cationic photopolymerization initiator system include "UV curing;
Science and Technology (UV CURING; SCIENCE AND TECHNOLOGY) "
[Pp. 23-76, S.I. Peter Purpose (S. PET
ER PAPPAS) Editing, A TECHNOLOGY MARKETING PUBLI
CATION)] and "Comments in Aug. Chem. (Comm
ents Inorg. Chem.) ”[B. Klingert, M .; Leader Car and A. Rolov (B. KLINGERT, M. RIEDIKER a
nd A. ROLOFF), Volume 7, No. 3, pp109-138
(1988)] and the like.
One or more of these may be used.

Particularly preferred cationic photopolymerization initiator systems used in the first to fourth aspects of the present invention include diaryl iodonium salts, triaryl sulfonium salts, iron allene complexes and the like.

Preferred diaryl iodonium salts as the cationic photopolymerization initiator system are iodonium tetrafluoroborate, hexafluorophosphate, hexafluoroarsenate and hexafluoroantimonate as shown in the photoradical polymerization initiator system. Trifluoromethane sulfonate etc. are mentioned.
Preferred triarylsulfonium salts are triphenylsulfonium, 4-tert-butyltriphenylsulfonium, tris (4-methylphenyl) sulfonium and tris (4-methoxyphenyl).
Examples thereof include sulfonium, sulfonium tetrafluoroborate such as 4-thiophenyltriphenylsulfonium, hexafluorophosphate, hexafluoroarsenate and hexafluoroantimonate.

Examples of the cationic photopolymerization initiator system that can be used in the first and third aspects of the present invention include diphenyliodonium trifluoromethanesulfonate, diphenyliodonium tetrafluoroborate, diphenyliodonium hexafluorophosphate, diphenyliodonium hexafluoroantimonate and the like. It can be illustrated.
They can also be used as a radical initiator system in the present invention.

If desired, the photosensitive composition of the present invention may contain a polymeric binder (binder), a thermal polymerization inhibitor, a silane coupling agent, a plasticizer, a colorant and the like. The polymer binder improves the film-forming property and film thickness uniformity of the composition before forming a hologram, and the interference fringes formed by polymerization by irradiation with laser light or light having excellent coherence It is used for stable existence until the exposure. The polymer binder may be one having good compatibility with the cationically polymerizable monomer or the radically polymerizable monomer, and specific examples thereof include chlorinated polyethylene, polymethylmethacrylate, methylmethacrylate and other alkyl (meth) acrylates. Examples thereof include copolymers of 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.

In the composition of the photosensitive composition of the present invention, the radical polymerizable monomer (a) is 30 to 9 relative to the total weight of the composition (excluding the solvent in the second and fourth embodiments).
0 wt% (particularly 40 to 70 wt%), cationically polymerizable monomer (b) is 2 to 70 wt% (particularly 10 to 50 wt%), and photoradical polymerization initiator system (c) is 0.3 to 8 wt% (particularly 1 to 10 wt%).
5 wt%) and the photo-cationic polymerization initiator system (d) is 0.3
-8 wt% (particularly 1-5 wt%) is preferable.

The photosensitive composition of the present invention may be prepared by a conventional method. For example, the above-mentioned essential components (a)-
(D) and optional components as they are, or as a solvent (for example, a ketone solvent such as methyl ethyl ketone, methyl isobutyl ketone, acetone, and cyclohexanone; an ester solvent such as ethyl acetate, butyl acetate and ethylene glycol diacetate; and an aroma such as toluene and xylene). Group solvent, cellosolve solvent such as methyl cellosolve, ethyl cellosolve, butyl cellosolve, alcohol solvent such as methanol, ethanol, propanol, n-butyl alcohol, ether solvent such as tetrahydrofuran and dioxane, halogen solvent such as dichloromethane and chloroform) Can be prepared by mixing and mixing in a cool dark place using, for example, a high-speed stirrer.

In the production of the hologram of the present invention, the recording layer is prepared by coating the above-mentioned photosensitive composition on a transparent support such as a glass plate, a polyethylene terephthalate film, a polyethylene film or an acrylic plate by a usual method. Can be formed by drying. Although the coating amount is appropriately selected, for example, dry coating weight may be ^{1g / m 2 ~50g / m 2} . Further, usually, a polyethylene terephthalate film, a polyethylene film, a polypropylene film or the like is provided as a protective layer on the recording layer for use. 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.

The recording layer thus prepared has a laser beam or light having excellent coherence (for example, a wavelength of 300 to 1).
The radical-polymerizable monomer (a) is polymerized by an ordinary holographic exposure device using (200 nm light), and interference fringes are recorded therein. Next, in order to further polymerize the cationically polymerizable compound (b) which remains unreacted, as a second exposure, the photocationic polymerization initiator system (d) is exposed to ultraviolet light (for example, a wavelength of 200 to 400 nm).
Light) is applied to the entire surface of the hologram. As a lamp,
It is preferable to use a reflex lamp, a metal halide lamp, a high pressure mercury lamp, or the like. At this time, the radically polymerizable monomers that remain unreacted may be simultaneously cured.

Next, the second exposed film is treated with 100 to 18
The mixture is heated at 0 ° C. for 1 to 120 minutes, and in the first and third aspects, the evaporative decomposition product generated by the decomposition of the photocationic polymerization initiator system by the second exposure and, in some cases, the evaporative unreacted monomer. In the second and fourth embodiments, the volatile film is evaporated by evaporation of the solvent and optionally the evaporative decomposition product from the photocationic polymerization initiator system generated by the second exposure and optionally the evaporative unreacted monomer. At the same time as the thickness is reduced, interference fringes due to the difference in refractive index are formed. As a result, the interference fringe spacing decreases and the reproduction wavelength changes to the short wavelength side. At this time, the ultraviolet irradiation amount, the heating temperature,
By controlling the heating time, the amount of change in wavelength can be controlled. If the heating temperature is lower than 100 ° C., the evaporation of moisture contained in the photosensitive composition is insufficient, which is not preferable. If the heating temperature exceeds 180 ° C., the polymer may turn yellow, and the polymer becomes colorless and transparent. In rare cases, the diffraction efficiency may decrease.

Next, a specific example of wavelength control will be described.
It is desirable to set the display color of the head-up display to around 540 nm in view of the sensitivity and color tone of the human eye. However, as described above, since the oscillation wavelength of the ion laser is not in the vicinity of this, it is necessary to control the wavelength after recording.
FIG. 1 shows the change in the relationship between the oscillation wavelength and the reproduction wavelength of the argon laser (Ar) and the krypton laser (Kr) depending on the rate of change in the film thickness of the hologram.

From this figure, for example, to set the hologram reproduction wavelength to 540 nm, a krypton laser of 568 nm is used.
The recording may be performed by, and the film may be shrunk to a film thickness of 95% at the time of recording by heat treatment.

[0039]

【Example】

Example 1 An example of the wavelength control method of the present invention will be described. The following components were mixed and dissolved to prepare a light-sensitive material. Radical polymerizable monomer: bis (4-acryloxydietoxyphenyl) methane 22% by weight Cationic polymerizable monomer: pentaerythritol polyglycidyl ether 11 Sensitizer: 3,9-diethyl 3'-carboxymethyl-2 , 2'-Thiacarbocyanine iodine salt 0.1-Active radical generating compound / acid generating compound: diphenyliodonium trifluoromethane sulfonate 1.2-Binder: methyl methacrylate / ethyl acrylate / acrylic acid copolymer (copolymerization ratio = 45/49/6) 10 ・ Organic solvent: Normal butyl alcohol 23 Methyl isobutyl ketone 18 Toluene 5 Methyl ethyl ketone 9.7

This photosensitive material was coated on a glass substrate using an applicator with a gap length of 0.1 mm and dried at 90 ° C. for 5 minutes. A 125 μm-thick polyethylene terephthalate film was laminated on this photosensitive film using a rubber roller to obtain a recording dry plate.

Hologram exposure was performed on this recording dry plate by using an optical system shown in FIG. The exposure energy at this time is 60 mJ / cm
^{And 2} . In FIG. 2, 1 is a mirror, 2 is a half mirror, 3 is a special filter (laser light diffusion), 4
Is a hologram plate, 5 is a laser, 6 is a laser beam, and 7 is laser diffused light. After completion of the laser exposure, exposure was performed for 70 seconds at an intensity of 57 mW / cm ² using a high pressure mercury lamp, and irradiation with ultraviolet rays having an energy amount of about 4 J / cm ² was performed. As a result of evaluating the characteristics of the hologram obtained at this point using a spectrophotometer, a reproduction wavelength of 560 nm and a diffraction efficiency of 9
0% was obtained.

Further, this hologram was subjected to 60 ° C. at 120 ° C.
A heat treatment for 1 minute was performed. As a result of weighing the weight change during this heat treatment with a precision balance, it was reduced by about 3.5%. The hologram obtained had a reproduction wavelength of 541 nm and a diffraction efficiency of 90%, and the reproduction wavelength was almost the same as the target value.

In order to confirm what is the volatile matter that causes the above-mentioned weight change, the hologram films before and after heating were peeled off, extracted with methanol, and water was added to the filtrate for liquid chromatography. As a developing solvent, a 7: 3 mixed solution of methanol and water was used. The boiling point of the decomposition product of the photosensitive material and the organic solvent having the above composition is 188 ° C. for the decomposition product of the polymerization initiator system iodobenzene, 118 ° C. for normal butyl alcohol, 117 ° C. for methyl isobutyl ketone, 111 ° C. for toluene, and 80 ° C. for methyl ethyl ketone. ℃. From the above chromatogram, it was found that the decomposed product of the photosensitive material and the organic solvent remaining in the photosensitive film when dried at 90 ° C. were evaporated by heating at 120 ° C. for 60 minutes.

As a result of using this hologram as a combiner for a head-up display, a bright and clear display image was obtained without image distortion.

[0045]

According to the present invention, the film thickness of the hologram can be controlled by controlling the amount of evaporation of the organic solvent, unreacted monomer, decomposition products of the polymerization initiator system, etc. remaining in the dry plate after the first and second exposures. The rate of change can be controlled to obtain a desired reproduction wavelength.

[Brief description of the drawings]

FIG. 1 is a diagram showing a change in a relationship between an oscillation wavelength and a reproduction wavelength of various lasers depending on a change rate of a film thickness of a hologram.

FIG. 2 is a diagram showing an optical system when hologram exposure is performed on a recording dry plate made of a photosensitive material according to an embodiment of the present invention.

FIG. 3 is a diagram showing an outline of a head-up display.

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI Technical indication location G03F 7/20 G03F 7/20 7/26 521 7/26 521 G03H 1/02 G03H 1/02 (72) Invention Atsuro Ishizuka 14 Iwatani, Shimohakaku-cho, Nishio-shi, Aichi Prefecture Japan Auto Parts Research Institute, Inc. (72) Inventor Kazuhiko Yoshida 14 Iwatani, Shimohakaku-cho, Nishio City, Aichi Prefecture Japan Auto Parts Research Institute (72) Invention Atsushi Hashikawa 14 Iwatani, Shimohakaku-cho, Nishio-shi, Aichi Stock company Japan Automotive Parts Research Institute (72) Inventor Tomoyuki Kanda 1-1, Showa-cho, Kariya city, Aichi Nihon Denso Co., Ltd. (72) Inventor Sato Akihiko 19-17 Ikedanaka-cho, Neyagawa-shi, Osaka Prefecture Japan Paint Co., Ltd. (72) Inventor Kenzo Mizutani 19-17 Ikedanaka-cho, Neyagawa-shi, Osaka Prefecture Japan Paint Co., Ltd. (72) Inventor Masami Kawabata Neyagawa, Osaka Prefecture 19-17 Ikedanaka-cho, Niigata Japan Paint Co., Ltd.

Claims (7)

[Claims] 1. A method for producing a hologram in which interference fringes produced by interference of laser light or light having excellent coherence are recorded as fringes having different refractive indices, comprising: (a) a radical-polymerizable monomer; (b) cationic polymerization. Radical monomer, (c) a radical photopolymerization initiator system that polymerizes the radical polymerizable monomer by being exposed to the laser light or light having excellent coherence, and (d) a wavelength different from the wavelength of the light of (c) A photo-cationic polymerization initiator system that polymerizes the above-mentioned cationically polymerizable monomer upon exposure to ultraviolet light and forms an evaporative decomposition product that evaporates by heating after being irradiated with ultraviolet light; A film is formed, and the film is subjected to a first exposure with the laser light for forming a hologram or a light having excellent coherence, and then Performing a second exposure to ultraviolet rays of a wavelength different from the wavelength of the light used for the entire surface to the first exposure of the film, 100
The method according to claim 1, wherein the film is heated at 180 ° C. for 180 minutes to evaporate the evaporative decomposition product. 2. A method for producing a hologram in which interference fringes produced by interference of laser light or light having excellent coherence are recorded as fringes having different refractive indexes, wherein (a) a radical-polymerizable monomer and (b) a cation-polymerized monomer. Radical monomer, (c) a radical photopolymerization initiator system for polymerizing the radical-polymerizable monomer by being exposed to the laser beam or light having excellent coherence, (d) having a wavelength different from that of the light of (c) A photocationic polymerization initiator system which is exposed to ultraviolet light to polymerize the above cationically polymerizable monomer, and (e) the above (a) to (d) are dissolved or dispersed, and 10
A photosensitive composition containing a solvent that evaporates at 0 to 180 ° C. is applied to a substrate to form a film, and the film is subjected to the first exposure using the laser beam or light having excellent coherence for forming a hologram. Then, a second exposure is performed by irradiating the entire surface of the film with an ultraviolet ray having a wavelength different from the wavelength of the light used for the first exposure, and 100
The film is heated and dried at ˜180 ° C. for 1 to 120 minutes to evaporate the solvent and the volatile product when the initiator system produces the volatile product by the ultraviolet irradiation. The manufacturing method. 3. A radical photopolymerization initiation in which (a) a radical-polymerizable monomer, (b) a cationic-polymerizable monomer, (c) the photopolymerization of the radical-polymerizable monomer by being exposed to the laser beam or light having excellent coherence. The agent system and the light that forms an evaporative decomposition product that is exposed to ultraviolet light having a wavelength different from the wavelengths of the light in (d) and (c) to polymerize the cationically polymerizable monomer and that is evaporated by ultraviolet irradiation when heated later. A cationic polymerization initiator system, a photosensitive composition containing a is applied to a substrate to form a film, and the film is subjected to a first exposure with the laser light for forming a hologram or light having excellent coherence, Then, the entire surface of the film is subjected to a second exposure of irradiating ultraviolet rays to evaporate the evaporative component present in the composition to obtain a hologram. How to obtain a low reproduction wavelength only 10~100nm than a recording wavelength. 4. A photo-radical polymerization initiation in which (a) a radical-polymerizable monomer, (b) a cation-polymerizable monomer, (c) the above-mentioned laser beam or light having excellent coherence is exposed to polymerize the above-mentioned radical-polymerizable monomer. Agent system, (d) a photo-cationic polymerization initiator system that polymerizes the cationically polymerizable monomer by being exposed to an ultraviolet ray having a wavelength different from that of light, and (e) the above (a) to (d) To dissolve or disperse
A photosensitive composition containing a solvent that evaporates at 0 to 180 ° C. is applied to a substrate to form a film, and the film is subjected to the first exposure using the laser beam or light having excellent coherence for forming a hologram. Then, a second exposure is performed by irradiating the entire surface of the film with ultraviolet rays to obtain a hologram by evaporating the evaporative component present in the composition, and the hologram provides a hologram having a recording wavelength of 10 to 100 nm. A method of obtaining a low reproduction wavelength. 5. The step of evaporating causes the film to become 100
The method of heating at -180 ° C for 1 to 120 minutes.
Or the method of 4. 6. The method according to claim 3, wherein the evaporative component is at least one of an unreacted monomer, a solvent and a decomposition product of an initiator system. 7. The method according to claim 3, wherein the photosensitive composition further comprises a sensitizer.