JPH07104643A - Hologram recording material and medium for hologram recording - Google Patents

Abstract

PURPOSE:To provide a hologram recording material and medium for hologram recording having excellent heat resistance, weather resistance, such as strength, and chemical stability and having excellent resolution, diffraction efficiency, transparency and reconstructing wavelength reproducibility particularly in dry development processing. CONSTITUTION:This hologram recording material and medium for hologram recording are composed of a reactive oligomer (A) having at least >=1 pieces of polymerizable ethylenic unsatd. bonds, a compd. (B) having at least >=1 pieces of polymerizable ethylenic unsatd. bonds and having a refractive index different from the refractive index of this reactive oligomer (A) and a photopolymn. initiator (C) which activates the compd. having the ethylenic unsatd. bonds by exposing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hologram recording material and a hologram recording medium capable of forming a hologram by forming a film on a substrate and exposing in an optical system. The present invention relates to a hologram recording material and a hologram recording medium which are excellent in weather resistance such as heat resistance and storage stability and are excellent in hologram characteristics such as resolution, diffraction efficiency and transparency.

[0002]

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

In recent years, a hologram optical element (H) typified by a head-up display (HUD) mounted on an automobile or the like has been used from one utilizing a fine decoration effect.
Application to OE) is considered.

As described above, holograms are used for displays, optical elements, or multiplex recording of images, so that hologram recording materials having improved resolution, diffraction efficiency, transparency, sensitivity, and weather resistance are desired as the applications are expanded. Has been. Therefore, the hologram recording material is required to be highly sensitive to laser light having a visible oscillation wavelength and exhibit high resolution. In practice, the hologram diffraction efficiency, the reproducibility of the reproduction light wavelength, and the It is necessary that the hologram characteristics such as the bandwidth (half-value width of the reproduction light peak) be compatible with the target hologram.

The hologram recording material for the HOE has a diffraction efficiency of 90 at a spatial frequency of 5000 to 6000.
% Or more, band width (half-width of reproduced light peak) is 20 to 3
0 nm, the peak wavelength of the reproduction wavelength is 5 nm from the shooting wavelength
It is desirable that the content be within the range, and it is also necessary that these holograms have excellent storage stability and weather resistance over a long period of time. In particular, the on-vehicle HUD is resistant to heat pressing when it is incorporated into laminated glass, and
1000 hours at 00 ° C and 100 in fade meter
Even if left for 0 hours, the hologram characteristics should not change.

Up to now, as a hologram recording material,
Light-sensitive materials such as silver halide emulsions and hardened dichromated gelatin have been commonly used. Although dichromated gelatin has high diffraction efficiency and low noise characteristics, it has a short shelf life and is easily deteriorated, and the manufactured hologram has poor weather resistance such as humidity resistance and heat resistance, and hologram recording is possible even in silver halide emulsion. There is a problem in that the manufacturing process of the recording medium and the manufacturing process of the hologram become complicated.

To solve the above problems, a binder resin as a carrier is used as a hologram recording material used in the production of holograms having excellent weather resistance and storage stability, and hologram characteristics such as resolution, diffraction efficiency and transparency. A hologram recording material using poly-N-vinylcarbazole may be mentioned, for example, 1,4,5,6,7,7-hexachloro-5-nobornene-anhydrous described in JP-A-60-227280. Holographic recording material comprising 2,3-dicarboxylic acid and dye, JP-A-60-45283
Patent Document, a hologram recording material comprising a sensitizer and a cyclic cis-α-dicarbonyl compound as a crosslinking agent,
2, 3 described in JP-A-60-260080
There is a hologram recording material composed of bornandione and thioflavin T, and a hologram recording material composed of thioflavin T and iodoform described in JP-A-62-123489.

Further, Japanese Patent Application Laid-Open No. 60-88005 describes a photocurable resin composition material in which a constituent of a photopolymerization initiator is a combination of 3-ketocoumarins and a diaryl iodonium salt as a photocurable material with high sensitivity. Further, a gram recording material in which the photopolymerization initiator is combined with a polymer serving as a carrier and polymethylmethacrylate is disclosed in Japanese Patent Application Laid Open
No. 31590.

[0009]

However, the above-mentioned hologram recording material is a photosensitive resin composition whose main component is poly-N-vinylcarbazole, which has high resolution and high diffraction efficiency. Due to the crystallinity of N-vinylcarbazole itself or the solubility in a solvent, the resulting photosensitive resin composition is liable to become cloudy or white, and is inferior in transparency, which causes a problem in hologram reproducibility.

The latter is chemically stable and has high resolution,
Although it has high sensitivity, in the case of wet treatment, the polymer serving as a carrier causes some dissolution in the solvent in the swelling step,
There is a problem that uneven development is likely to occur, and since the glass transition temperature is around 100 ° C., there is a problem that heat resistance is poor.

Further, as a hologram recording material when a wet process is not carried out in the developing step after exposure to light, Japanese Patent Application Laid-Open No. 2-3 is referred to.
No. 081, a solvent-soluble thermoplastic resin, a liquid ethylenically unsaturated monomer, a photopolymerization initiator and a plasticizer are used in combination to form a refractive index image only in the exposure process. There is a photopolymerizable composition. However, this hologram recording material has a low sensitivity of 30 mJ / cm ^{2 at} 488 nm and a plasticizer remains, so that the wavelength of the reproduced light tends to shift to a short wavelength when exposed to high temperatures.
In addition, there is a problem that the heat resistance of the HUD is poor.

Therefore, the present invention is a hologram recording material and a hologram recording material which are excellent in heat resistance, weather resistance such as strength, and chemical stability, and particularly excellent in resolution, diffraction efficiency, transparency and reproduction wavelength reproducibility in dry development processing. Some provide media.

[0013]

The invention according to claim 1 is
25 to 75% of the reactive oligomer (A), a compound (B) having at least one polymerizable ethylenic unsaturated bond and having a refractive index different from that of the reactive oligomer (A), A hologram recording material comprising a photopolymerization initiator (C) which activates the polymerization of a compound having an ethylenically unsaturated bond.

The invention according to claim 2 is based on the invention according to claim 1, in which the reactive oligomer (A) has at least one polymerizable ethylenically unsaturated bond and has a degree of polymerization of 2 to 15 The hologram recording material is characterized in that

A third aspect of the present invention is the hologram recording material according to the first aspect, wherein the viscosity of the reactive oligomer (A) is in the range of 5000 to 110,000 cps at 50 ° C.

The invention according to claim 4 is the method according to claim 1 on a substrate.
The hologram recording medium is characterized in that a recording film made of the hologram recording material is formed, and an oxygen barrier film is formed on the recording film.

[0017]

According to the present invention, the reactive oligomer (A) having at least one polymerizable ethylenically unsaturated bond, the reactive oligomer (A) having at least one polymerizable ethylenically unsaturated bond, and the reactivity When the compound (B) having a refractive index different from that of the oligomer (A) and the photopolymerization initiator (C) that activates the compound having an ethylenically unsaturated bond upon exposure are exposed to light by laser irradiation. Due to the action of the photopolymerization initiator, the compound (B) having a polymerizable ethylenically unsaturated bond causes a polymerization reaction, and the reactive oligomer (A) also causes a polymerization reaction with itself or with the compound (B). , Compound (B) moves from the surroundings. Therefore, the concentration of the compound (B) becomes high in the portion of the laser irradiation portion where the optical interference is strong,
Further, the concentration of the compound (B) decreases at the site where the light interference action is weak. Further, since the reactive oligomer (A) and the compound (B) have different refractive indexes, refractive index modulation occurs, and hologram recording is performed. Further, since the carrier is the reactive oligomer (A), the compound (B) easily moves, and the unreacted reactive oligomer (A) can be polymerized and fixed by exposure to ultraviolet light or heating.

Further, the hologram recording medium of the present invention is excellent in reproducibility of the peak wavelength of reproduced light and its bandwidth, and is also excellent in weather resistance and chemical stability.

[0019]

EXAMPLES The present invention will now be described in detail based on examples. FIG. 1 is a schematic diagram illustrating the configuration of a hologram recording medium made of the hologram recording material of the present invention, and FIG. 2 is a schematic explanatory diagram illustrating a two-beam optical system for hologram imaging.

The reactive oligomer (A) of the hologram recording material of the present invention has at least one polymerizable ethylenic unsaturated bond, has a degree of polymerization of 2 to 15, and a weight average molecular weight of 8,000. The following are desirable,
Furthermore, the viscosity at 50 ° C is 5000 to 110,000c
It must be in the range of ps, have at least one polymerizable ethylenically unsaturated bond, and have good compatibility with the reactive oligomer (A) and the compound (B) having a different refractive index. When the weight average molecular weight of the reactive oligomer (A) exceeds 8000, the diffusion rate of the compound (B) decreases, and a dry process alone in the developing step does not produce a hologram with high diffraction efficiency.

Specific examples of the reactive oligomer (A) include radical polymerization type unsaturated polyesters, monofunctional and polyfunctional polyester acrylates, monofunctional and polyfunctional urethane acrylates, radical addition type polyenes / polythiols, and spirane resins / Examples thereof include polythiols, but are not limited thereto as long as the above conditions are satisfied.

The compound (B) having at least one polymerizable ethylenic unsaturated bond and having a different refractive index is a monomer containing at least one ethylenically unsaturated bond and having one functional group. It may contain a polyfunctional oligomer in addition to a certain vinyl monomer, or may be a mixture thereof. Further, when the reactive oligomer (A) is an aromatic oligomer, the compound (B) is an aliphatic monomer, and when the reactive oligomer (A) is an aliphatic oligomer, the compound (B) is an aromatic monomer. Combine. According to the theory of Kogelnik, it is preferable that the refractive index difference between the reactive oligomer (A) and the compound (B) is 0.03 or more.

Specific examples include (meth) acrylic acid, itaconic acid, maleic acid, (meth) acrylamide, diacetone acrylamide, and 2-hydroxyethyl (meth).
High boiling vinyl monomers such as acrylates, aliphatic polyhydroxy compounds such as ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, neopentyl glycol, 1,3-propanediol, 1,4-butanediol, 1,5- Pentanediol, 1,6-hexanediol, 1,10-
Decanediol, trimethylolpropane, pentaerythritol, dipentaerythritol, sorbitol,
Di- or poly (meth) acrylic esters such as mannitol, aromatic polyhydroxy compounds, for example, di- or poly (meth) acrylic acid esters such as hydroquinone, resorcin, catechol, pyrogallol, bisphenol A, ethylene oxide modification (meth) of isocyanuric acid Examples thereof include acrylic acid ester, but are not limited thereto.

The photopolymerization initiator (C) activates the polymerization of the reactive oligomer (A) and the compound having an ethylenically unsaturated bond such as the compound (B) upon exposure, and is, for example, polymerizable. A polymerization reaction occurs with the compound (B) having an ethylenically unsaturated bond, and the reactive oligomer (A) also undergoes a polymerization reaction with itself or with the compound (B). For example, organic peroxides and onium salts are preferable, and they can be sensitized with an organic dye compound. Specifically, as an example of the organic peroxide, first, tert-butyl peroxide-iso-butarate, 2,5-dimethyl-2,5-bis- (benzoyldioxy) hexane, 14-bis [α- ( tert-butyldioxy) -iso-propoxy] benzene, di-t
ert-butyl peroxide, 2,5-dimethyl-2,
5-bis (tert-butyldioxy) hexene hydroperoxide, α- (iso-propylphenyl) -i
so-propyl hydroperoxide, 2,5-bis (hydroperoxy) -2,5-dimethylhexane, ter
t-Butyl hydroperoxide, 1,1-bis (ter
t-butyldioxy) -3,3,5-trimethylcyclohexanone, butyl-4,4-bis (tert-butyldioxy) valerate, cyclohexanone peroxide, 2,2′5,5′-tetra (tert-butylperoxycarbonyl) benzophenone, 3, 3 ', 4,
4'-tetra (tert-butylperoxycarbonyl) benzophenone, 3,3 ', 4,4'-tetra (t
ert-amylperoxycarbonyl) benzophenone, 3,3 ′, 4,4′-tetra (tert-hexylperoxycarbonyl) benzophenone, 3,3′-bis (tert-butylperoxycarbonyl) -4,
4′-dicarboxybenzophenone, tert-butylperoxybenzoate, di-tert-butyldioxyisophthalate and the like can be mentioned.

Examples of onium salts are diphenyliodonium chloride, diphenyliodobromide, diphenyliodonium tetrafluoroborate, diphenyliodonium hexafluorophosphate, bis (p-tert-butylphenyl) iodonium hexafluorophosphate, bis (p-tert-tert-butyl). Butylphenyl) iodonium tetrafluoroborate, bis (p-tert-butylphenyl) iodonium chloride, bis (p-chlorophenyl) iodonium chloride, bis (p-chlorophenyl) iodonium tetrafluoroborate, triphenylsulfonium chloride, triphenylsulfonium bromide, Tri (4-methoxyphenyl) sulfonium tetrafluoroborate, tri (4-methoxy) Phenyl) sulfonium hexafluorophosphonate, tri (4-ethoxyphenyl) sulfonium tetrafluoroborate, triphenylphosphonium chloride, triphenylphosphonium bromide, tri (p-methoxyphenyl) phosphonium tetrafluoroborate, tri (p-methoxyphenyl) Examples thereof include phosphonium hexafluorophosphonate and tri (p-methoxyphenyl) phosphonium tetrafluoroborate.

Further, as the sensitizer of the present invention, organic dye compounds such as cyanine or merocyanine dyes, pyrylium or thiopyrylium salt dyes and coumarin dyes can be used.

Examples of cyanine or merocyanine dyes are fluorescein, rhodamine, 2'7'-dichlorofluorescein, 3,3'-dicarboxyethyl-2.
2'-thiocyanine bromide, anhydro-3,3'-
Dicarboxymethyl-2,2'-thiocyanine betaine, 1-carboxymethyl-1'-carboxyethyl-
2,2'-quinocyanine bromide, anhydro-3,
3'-dicarboxyethyl-5,5 ', 9-trimethyl-2,2'-thiacarbocyanine betaine, 3,3'-
Dihydroxyethyl-5,5'-dimethyl-9-ethyl-2,2'-thiacarbocyanine bromide, anhydro-3,3'-dicarboxymethyl-2,2'-thiacarbocyanine betaine, 2- [3- Ethyl-4-oxo-
5- (1-ethyl-4-quinolinidene) -ethylidene-
2-thiazolinidene-methyl] -3-ethylzenzoxazolium bromide, 3-ethyl-5- [2- (3-ethyl-2-benzothiazoylidene) -ethylidene] rhodanine, 3-ethyl-5- [ 2- (3-methyl-2 (3
H) -thiazolinidene) -ethylidene] -2-thio-
2,4-oxazalidione, 3-ethyl-5- (3-ethyl-zenzothiazolidene) rhodine, 2- (p-
Dimethylaminostyryl) -3-ethylbenzothiazolium iodide, 2- (p-dimethylaminostyryl)-
1-ethylpyridiniodide, 1,3'-diethyl-
2,2'-quinothiacyanine iodide and the like can be mentioned.

Examples of pyrylium or thiopyrylium salt dyes are 2-amino-4,6-bis (4-butoxyphenyl) thiopyrylium perchlorate and 2-hydroxy-4,6-bis (4-dimethylaminostyryl). )
Pyrylium perchlorate, 2-hydroxy-4,6-
Bis (4-dimethylaminostyryl) pyrrinium fluoroborate, 2-hydroxy-4,6-bis (4-dimethylaminostyryl) thiopyrrinium perchlorate, 2-hydroxy-4,6-bis (4-dimethylaminostyryl) ) Thiopyrylium fluoroborate, 2-amino-4,6-bis (4-butoxyphenyl) pyrylium perchlorate, 2-amino-4,6-bis (4-butoxyphenyl) pyrylium fluoroborate, 2-amino -4,6-bis (4-β-ethylstyryl) thiopyrylium fluoroborate and the like can be mentioned.

Examples of coumarin dyes include 3- (2 '
-Benzimidazole) 7-N, N-diethylaminocoumarin, 3,3'-carbonylbis (7-diethylaminocoumarin), 3,3'-carbonylbiscoumarin,
3,3'-carbonylbis (7-methoxycoumarin),
3,3′-carbonylbis (5,7-dimethoxycoumarin), 3,3′-carbonylbis (6-methoxycoumarin), 3,3′-carbonylbis (7-acetoxycoumarin), 3,3′-carbonyl Bis (5,7-di-is
o-propoxycoumarin), 3,3′-carbonylbis (5,7-di- n -propoxycoumarin), 3,3′-
Carbonylbis (5,7-di- n -butoxycoumarin), 3,3′-carbonylbis (7-dimethylaminocoumarin), 7-diethylamino-5 ′, 7′-dimethoxy-3,3′-carbonylbiscoumarin , 3-benzoylcoumarin, 3-benzoyl-5,7-dimethoxycoumarin, 3-benzoyl-6-methoxycoumarin, 3-
Benzoyl-7-methoxycoumarin, 3-benzoyl-
8-methoxycoumarin, 3-benzoyl-8-ethoxycoumarin, 3-benzoyl-6-bromocoumarin, 3-
Benzoyl-7-dimethylaminocoumarin, 3-benzoyl-7-diethylaminocoumarin, 3-benzoyl-
7-hydroaminocoumarin, 3-acetyl-7-diethylaminocoumarin, 3-acetyl-7-methoxycoumarin, 3-acetyl-5,7-dimethoxycoumarin, 7-
Examples thereof include dimethylamino-3- (4-iodobenzoyl) coumarin, 7-diethylamino-3- (4-iodobenzoyl) coumarin and 7-diethylamino-3- (4-diethylaminobenzoyl) coumarin.

As described above, the hologram recording material of the present invention contains 25 to 75% of the reactive oligomer (A) and 5 to 75% of the reactive oligomer (A).
Compound (B) having at least one 60% polymerizable ethylenically unsaturated bond and having a refractive index different from that of the reactive oligomer (A), and photopolymerization initiation for activating the compound (B) by exposure. Each of these components is appropriately selected by mixing with the agent (C), mixed at an arbitrary ratio and dissolved in a suitable solvent to obtain a photosensitive solution, which is then prepared using a spin coater, a roll coater, a bar coater, or the like. The photosensitive layer 3 is formed by applying it in a film form on a substrate 2 such as a glass plate, a polycarbonate plate, a polymethylmethacrylate plate, or a polyester film, and the hologram recording medium 1 shown in FIG. 1 is obtained. A protective layer 4 may be provided on the photosensitive layer 3 to block oxygen. The protective layer 4 is formed by, for example, laminating a plastic such as polyolefin, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol or polyethylene terephthalate, or an optically transparent material such as glass, laminating with an extruder, coating a solution, etc. To be done.

The mixing ratio of each component of the hologram recording material of the present invention is not specified, but it is desirable to adjust the hologram recording material so that the transmittance of irradiation light at the time of hologram photographing is 1% or more. . Further, various additives such as a known binder, plasticizer, thermal polymerization inhibitor, antioxidant or chain transfer agent may be added to the hologram recording material of the present invention, if necessary.

As an example of the constitution of the hologram recording material of the present invention, 25 to 75% of the reactive oligomer (A) having at least one polymerizable ethylenically unsaturated bond is contained.
The compound (B) having at least one polymerizable ethylenic unsaturated bond and having a refractive index different from that of the reactive oligomer (A) is 5 to 60%. The photopolymerization initiator (C) that activates the polymerization is 0.1 to 10%. The amount of the photopolymerization initiator and the sensitizer used is limited by the film thickness of the photosensitive layer film and its optical density (or optical density), and it is preferable to use the optical density within the range of 2 ( When the transmittance is used, the transmittance of the irradiation light at the time of hologram recording is 1%.
It is preferable that the range is as described above). If it deviates from this range, it becomes difficult to obtain a high diffraction efficiency and the sensitivity characteristic deteriorates.

FIG. 2 is a schematic diagram for explaining a two-beam optical system for hologram photographing, in which a laser beam 6 oscillated from a laser 5 passes through a mirror 7, a beam splitter 8, a spatial filter 9, and a lens 10. The hologram recording medium 1 is irradiated. In this embodiment, dry processing is performed without wet development processing.

In the step of exposing the interference pattern, a light source suitable for the hologram recording material of the present invention includes, but is not limited to, a helium-cadmium laser and an argon laser.

The post-exposure fixing step is carried out by exposure or heat treatment on the entire surface using a light source such as a helium-cadmium laser, an argon laser, a high pressure mercury lamp, or a xenon lamp.

By irradiating the hologram recording medium 1 with a laser beam, at least a polymerizable ethylenically unsaturated bond is present in the laser-irradiated region having a strong optical interference action.
Reactive oligomer (A) having at least one polymerizable compound, and a compound (B) having at least one polymerizable ethylenic unsaturated bond and having a refractive index different from that of the reactive oligomer (A)
And a photopolymerization initiator (C) that activates a compound having an ethylenically unsaturated bond upon exposure to light, thereby allowing polymerization by the action of the photopolymerization initiator when exposed to a laser beam. The compound (B) having an unsaturated bond undergoes a polymerization reaction, and the reactive oligomer (A) also undergoes a polymerization reaction with itself or with the compound (B), so that the compound (B) moves from the surroundings.
Therefore, in the part where the optical interference of the laser irradiation part is strong,
The concentration of the compound (B) increases, and the concentration of the compound (B) decreases at the site where the light interference action is weak. Further, since the reactive oligomer (A) and the compound (B) have different refractive indexes, refractive index modulation occurs, and hologram recording is performed.
Further, since the carrier is the reactive oligomer (A), the compound (B) easily moves, and the unreacted reactive oligomer (A) can be polymerized and fixed by exposure to ultraviolet light or heating.

Further, the hologram recording material of the present invention will be described with reference to specific examples.

Examples 1 to 4 Reactive oligomer having at least one polymerizable ethylenic unsaturated bond (A) Trifunctional oligoester acrylate 100 parts by weight (Aronix M- manufactured by Toagosei Kagaku Kogyo Co., Ltd.) 9050) ○ Compound (B) having a polymerizable ethylenic unsaturated bond and having a refractive index different from that of the reactive oligomer (A) 2-phenoxyethyl acrylate (POEA) 120 parts by weight ○ Photopolymerization initiator diphenyliodonium hexa Fluorophosphate 5 parts by weight ○ Sensitizer 3,3'-Carbonylbis (7-diethylamino) coumarin 0.5 parts by weight of a photosensitive solution was applied to a glass plate to a film thickness of about 20 μm, and polyvinyl alcohol was further added. A hologram recording medium was prepared by coating with a (PVA) film.

Hologram recording was performed on the produced hologram recording medium by using a two-beam optical system device used in ordinary hologram photography, using an argon laser as a light source to perform hologram recording with light of 488 nm.

The diffraction efficiency of this hologram was measured with a spectrophotometer (manufactured by JASCO Corporation). This device has a width of 3 mm
It is a photomultimeter with a slit, and can be installed on a circle with a radius of 20 cm centering on the sample.
Monochromatic light of m was incident at an angle of 45 °, and diffracted light from the sample was detected. The diffraction efficiency was defined as the ratio of the maximum value other than the specular reflection light and the value when the incident light was taken without the sample. Further, in Examples 2 to 3, in addition to 2-phenoxyethyl acrylate (POEA) of Example 1, a compound (B) having a polymerizable ethylenic unsaturated bond and having a refractive index different from that of the reactive oligomer (A). [Bisphenol A diacrylate: BPADA, 2- (2-naphthyloxy) ethyl acrylate: NOEA, 2,4,6-
Tribromophenyl acrylate: TBPA], and the same hologram recording medium for each of them.
A hologram was prepared and the diffraction efficiency was measured. The results are shown in Table 1.

[0041]

[Table 1]

Examples 5 to 8 Examples 1 to 8 except that 2,2 ', 5,5'-tetra (tert-butylperoxycarbonyl) benzophenone is used as the photopolymerization initiator (C) of Example 1. A hologram recording medium and a hologram were prepared in the same manner as in 4, and the diffraction efficiency was measured. The results are shown in Table 2.

[0043]

[Table 2]

[Examples 9 to 12] 3 parts of the sensitizer of Example 1 were used.
A hologram recording medium and a hologram were prepared in the same manner as in Examples 1 to 4 except that-(2'-benzimidazole) -7-diethylaminocoumarin was used, and the diffraction efficiency was measured. The results are shown in Table 4.

[0045]

[Table 3]

[Examples 13 to 16] Examples 1 to 16 except that 2-amino-4,6-bis (4-methoxy-β-ethylstyryl) thiopyrylium fluoroborate is used as the sensitizer of Example 1. A hologram recording medium and a hologram were prepared in the same manner as in 4, and the diffraction efficiency was measured. The results are shown in Table 4.

[0047]

[Table 4]

Examples 17 to 20 Reactive oligomer having at least one polymerizable ethylenic unsaturated bond (A) 100 parts by weight of aromatic urethane acrylate (Aronix M-1300 manufactured by Toagosei Co., Ltd.) ) Compound (B) having a polymerizable ethylenically unsaturated bond and having a refractive index different from that of reactive oligomer (A) 1,6-hexanediol diacrylate (HDODA) 120 parts by weight Photopolymerization initiator diphenyl Iodonium hexafluorophosphate 5 parts by weight ○ Sensitizer 3,3'-Carbonylbis (7-diethylamino) coumarin 0.5 parts by weight A photosensitive solution was prepared in the same manner as in Example 1 to prepare a hologram recording medium and a hologram. , Having a polymerizable ethylenically unsaturated bond, and having a refractive index with the reactive oligomer (A) Different compounds (B) (diethylene glycol diacrylate: DEGA, neopentyl glycol:
Three kinds of NPGDA and trimethylolpropane triacrylate: TMPTA) were listed, a hologram recording medium and a hologram were prepared in the same manner, and the diffraction efficiency of each was measured. The results are shown in Table 5.

[0049]

[Table 5]

Comparative Example 1 A hologram recording medium and a hologram were prepared in the same manner as in Example 1 except that 1,6-hexanediol diacrylate was used instead of 2-phenoxyethyl acrylate of Example 1. I couldn't make a hologram.

Comparative Example 2 Instead of 1,6-hexanediol diacrylate (HDODA) of Example 17, 2 was used.
Example 1 with the exception of phenoxyethyl acrylate
When a hologram recording medium and a hologram were prepared in the same manner as in, and the diffraction efficiency was measured, the diffraction efficiency was 10%.

Comparative Example 2 The trifunctional oligoester acrylate of Example 1 was converted into urethane acrylate (UX-3204 manufactured by Nippon Kayaku Co., weight average molecular weight: 11500 ± 1).
When a hologram recording medium and a hologram were prepared and the diffraction efficiency was measured in the same manner as in Example 1 except that the above was set to 100), the diffraction efficiency was 45%.

The holograms produced and evaluated in the above Examples 1 to 20 were exposed to the environment of 25 ° C. and 60% RH for 180 days.
The hologram did not change even when left at 120 ° C. for 24 hours, and no decrease in diffraction efficiency was observed.

[0054]

As described above, the present invention has a reactive oligomer (A) having at least one polymerizable ethylenic unsaturated bond and at least one polymerizable ethylenic unsaturated bond. And a photopolymerization initiator (C) which activates the compound having an ethylenically unsaturated bond upon exposure to light (C), which has a refractive index different from that of the reactive oligomer (A), It is possible to provide a hologram recording material and a hologram recording medium which have high sensitivity in dry processing, high resolution, high diffraction efficiency, high transparency, excellent weather resistance such as heat resistance, and are chemically stable. HOE with extremely high performance requirements
It can be used for a hologram recording material.

[Brief description of drawings]

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

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

[Explanation of symbols]

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

Claims (4)

[Claims] 1. A reactive oligomer (A) having at least one polymerizable ethylenic unsaturated bond, and at least one polymerizable ethylenically unsaturated bond, and said reactive oligomer (A). ), And a photopolymerization initiator (C) which activates the polymerization of the compound having an ethylenically unsaturated bond upon exposure to light, and a hologram recording material. 2. The reactive oligomer (A) has at least one polymerizable ethylenically unsaturated bond and has a degree of polymerization of 2 to 15. Holographic recording material. 3. The viscosity of the reactive oligomer (A) is 5
The hologram recording material according to claim 1, which is in a range of 5000 to 110,000 cps at 0 ° C. 4. A hologram recording medium characterized in that a recording film made of the hologram recording material according to claim 1 is formed on a substrate, and an oxygen blocking film is formed on the recording film.