KR101138391B1 - Photopolymerizing composition and photopolymerizing recording medium manufactured using the same and used to manufacture 3D optical memory - Google Patents

Abstract

1.0 to 99.9 wt% of at least one photopolymerizable compound; 0.05 to 0.5% by weight of at least one photosensiitizer selected from photochromic compounds exhibiting photochromic by non-coherent UV light; 0.2 to 6.0% by weight of a disclosure reagent which is activated by visible light in the presence of a photochromic compound having a photochromic structure to photopolymerize the photopolymerizable compound; 0 to 97.5 weight percent of a polymeric binder; Plasticizer 0-6.0 wt%; And a photopolymerizable composition comprising 0 to 3.0% by weight of a nonpolymerizable solvent and a photopolymerizable recording medium prepared using the same. Since the photopolymerizable recording medium according to the present invention has high angular diffraction selectivity, the photopolymerizable recording medium can be usefully used for the manufacture of ultra-high information capacity three-dimensional hologram optical memory.

Description

Photopolymerizing composition and photopolymerizing recording medium manufactured using the same and used to manufacture 3D optical memory}

The present invention relates to a photopolymerizable composition and a photopolymerizable recording medium manufactured using the same, and more particularly, to a photopolymerizable composition and a photopolymerizable recording medium for manufacturing a three-dimensional, ultra-high information capacity optical memory manufactured using the same.

Holograms record interference patterns by coherent laser light on photosensitive materials, for example, and are used in fields such as optical memory, three-dimensional image display, and information processing because they are multifunctional. .

In particular, the manufacture of optical memories can be made by forming deep holograms using the change in refractive index induced due to the change in density of the material constituting the thick photopolymerizable recording medium. The hologram can be generated by exposing the photosensitive film for recording containing the photopolymerizable monomer of the recording medium to photopolymerization by exposing to a laser beam of appropriate intensity. The degree of polymerization of the photosensitive film depends on the active light intensity incident on the recording medium. Generated images with sets of lines of different intensity are recorded based on the polymer density change. This generated polymer, which has a refractive index different from that of the initial monomers, is characterized by the refractive index which depends on the light intensity in other regions of the photosensitive film. These differences are used to reproduce the image using light wave phase recovery. Deep hologram recording may be the result of photobleaching of photosensitive media components, i.e. laser beam penetration into the recording medium, in the hologram recording process. Deep hologram recording on thick films requires high angular selectivity of hologram recording and image reproduction, and this angular selectivity can greatly increase the information capacity.

Photopolymerizable media using monomer-oligomeric compositions and photoinitiation systems are well known. The photopolymerizable medium further includes a photobleaching dye and a open reagent (Carretero L., Blaya S., Mallavia R., et al., Appl. Opt. 1998. V. 37. p. 4496). Acquiring phase holograms requires additional post-exposure and thermal treatments, which makes the use of archive optical memory devices difficult.

U.S. Patent 5,230,986 discloses a photocurable composition consisting essentially of a free radically polymerizable compound, an electron donating initiator, and a photochromic benzospiropyran compound represented by the following formula (I). The benzospiropyran compound is ring-opened by exposure to a first actinic ray or heat to form a merocyanine compound of formula (II). The merocyanine compound is exposed to a second actinic ray to generate free radicals, and the free radicals produced by the benzospiropyran compound photopolymerize the polymerizable compound to cure the composition.

In formulas (I) and (II), X ₁ and X ₃ are independently selected from the group consisting of hydrogen, iodo, nitro, cyano, bromo, chloro, fluoro and amino, X ₁ And at least one of X ₃ is not hydrogen, and X ₂ is selected from the group consisting of hydrogen, alkoxy, carboxy, ester, and amino.

As represented by the above scheme, the benzospiropyrane compound undergoes reversible intramolecular conversion by ultraviolet irradiation or heating to produce a merocyanine isomer. When the colored merocyanine forms are irradiated with visible light in the presence of a reducing agent and an olefinically unsaturated compound, radicals that initiate polymerization occur. The colored merocyanine form can act as a visible light initiator. Photopolymerization may be performed by visible light absorbed by the merocyanine isomer. Photopolymerizable recording media utilizing such photopolymerizable polymers are spontaneously desensitized when the ultraviolet (UV) light irradiation is stopped or the layer is cooled.

A disadvantage of such photopolymerizable recording media is that additional light sources or thermal energy are required during hologram recording by a visible light laser. This complicates the structure of the 3D image forming apparatus. The concentration of merocyanine isomer is kept constant by constant UV irradiation or heating, thereby preventing light from penetrating deep into the recording medium. This excludes the possibility of writing deep holograms, thus reducing angular selectivity and information storage capacity. In addition, thermal distortion of the interference fringe occurs by recording medium heating, thereby reducing the resolution capability. In addition, since such media are liquid, they require a continuous post-exposure process even after hologram recording. This causes an increase in power consumption and an increase in optical memory formation time.

These drawbacks are due to the insufficient lifetime of the photoinduced structure of the photochromic compound which acts as a photosensitizer in the photopolymerizable composition used to form the recording layer of the photopolymerizable recording medium. do. In addition, such photopolymerizable compositions do not include polymeric binders or components that promote media photopolymerization during hologram recording.

According to one aspect of the present invention, there is provided a photopolymerizable composition capable of increasing the angular selectivity of a photopolymerizable recording medium for hologram recording and image reproduction by deep hologram recording in a thick photosensitive film.

According to one aspect of the present invention, there is provided a photopolymerizable recording medium manufactured using the above photopolymerizable composition. This photopolymerizable recording medium can be used for the production of ultra-high information capacity three-dimensional hologram optical memory and for the production of simplified optical hologram recording elements.

In one aspect of the invention, 1.0 to 99.9% by weight of at least one photopolymerizable compound;

0.05 to 0.5% by weight of at least one photosensiitizer selected from photochromic compounds exhibiting photochromic by non-coherent UV light;

0.2 to 6.0% by weight of a disclosure reagent which is activated by visible light in the presence of a photochromic compound having a photochromic structure to photopolymerize the photopolymerizable compound;

0 to 97.5 weight percent of a polymeric binder;

Plasticizer 0-6.0 wt%; And

There is provided a photopolymerizable composition comprising 0 to 3.0% by weight of a nonpolymerizable solvent.

In one aspect of the invention,

Transparent substrates; And a photosensitive layer for recording stacked on the transparent substrate, wherein a photopolymerizable recording medium is provided.

The recording photosensitive film may include 1.0 to 99.9% by weight of at least one photopolymerizable compound;

0.05 to 0.5% by weight of at least one photosensiitizer selected from photochromic compounds exhibiting photochromic by non-coherent UV light;

0.2 to 6.0% by weight of a disclosure reagent which is activated by visible light in the presence of a photochromic compound having a photochromic structure to photopolymerize the photopolymerizable compound;

0 to 97.5 weight percent of a polymeric binder;

Plasticizer 0-6.0 wt%; And

0-3.0 weight% of nonpolymerizable solvents are included.

According to one aspect of the present invention, the photosensitizer is a photochromic compound or dihetharyl ethene having a long lifespan in a photoinduced form, such as a benzothiazolene spiropyran compound, a phenoxynaphthacequinone compound, and mixtures thereof Thermally irreversible photochromic compounds such as compounds (dihetarylethenes), handymid compounds (fylgimides), and mixtures thereof.

In another aspect of the present invention, there is provided a method for hologram recording on the photopolymerizable recording medium of the present invention described above,

Irradiating non-coherent UV light on the photosensitive film of the recording medium to convert the photochromic compound into a colored form; And

Irradiating the photosensitive film with an interference fringe of a reference beam and an object beam split from the coherent visible light laser light, the photochromic compound of the colored form and the presence of the open reagent There is provided a hologram recording method comprising photopolymerizing the photopolymerizable compound using free radicals to record the interference fringe on the photosensitive film as a difference in refractive index.

In another aspect of the present invention, there is provided a method for reproducing hologram recording recorded on the recording medium, wherein the hologram recording reproduces the hologram recording by irradiating the recording medium with only the reference light used when recording the hologram on the recording medium. A playback method is provided.

In the photopolymerizable composition and the photopolymerizable recording medium according to one aspect of the present invention, the combination of the above-described special photochromic photosensitizer and open initiator acts as a photoinitiator for photopolymerizing the photopolymerizable compound. The photosensitizer is converted into a photoinduced structure in the form of colored by non-coherent UV light. The release initiator can be activated by visible light in the presence of this colored form of a light guide structure to initiate photopolymerization of the photopolymerizable compound.

The photopolymerizable recording medium according to another aspect of the present invention including a photosensitive film for recording formed using the photopolymerization composition can be usefully used as a recording medium for hologram recording. Also, the photopolymerizable recording medium according to one aspect of the present invention does not require post exposure and heating after hologram recording.

Some of the additional aspects and / or advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or will be learned by practice of the invention.

These and / or other aspects and advantages of the present invention will become more apparent and more readily understood from the following description of the embodiments when considered in conjunction with the accompanying drawings:

1 shows a graph of diffraction efficiency versus angle when 5.5 mW / cm ² Ar laser light is irradiated to a diffraction grating in a recording medium according to one embodiment of the present invention.

Hereinafter, an embodiment of a photopolymerizable composition and a photopolymerizable recording medium manufactured using the same according to various aspects of the present invention will be described in detail.

As described above, the photopolymerizable composition according to the embodiment of the present invention,

1.0 to 99.9 wt% of at least one photopolymerizable compound; 0.05 to 0.5% by weight of at least one photosensiitizer selected from photochromic compounds exhibiting photochromic by non-coherent UV light; 0.2 to 6.0% by weight of a disclosure reagent which is activated by visible light in the presence of a photochromic compound having a photochromic structure to photopolymerize the photopolymerizable compound; 0 to 97.5 weight percent of a polymeric binder; Plasticizer 0-6.0 wt%; And 0 to 3.0% by weight of a non-polymerizable solvent.

As described above, the photopolymerizable recording medium according to the embodiment of the present invention,

Transparent substrates; And a recording photosensitive layer laminated on the transparent substrate, wherein the recording photosensitive film comprises: 1.0 to 99.0 wt% of at least one photopolymerizable compound; 0.05 to 0.5% by weight of at least one photosensiitizer selected from photochromic compounds exhibiting photochromic by non-coherent UV light; 0.2 to 6.0% by weight of a disclosure reagent which is activated by visible light in the presence of a photochromic compound having a photochromic structure to photopolymerize the photopolymerizable compound; 0 to 97.5 weight percent of a polymeric binder; Plasticizer 0-6.0 wt%; And 0 to 3.0% by weight of a non-polymerizable solvent.

Any kind of photosensitizer capable of absorbing UV light can be used. The composition of the present invention comprises a photochromic compound having a long life time of a photoinduced structure selected from benzothiazolene spiropyran compound (II), phenoxynaphthacequinone compound (III) and mixtures thereof; Or a thermally irreversible photochromic compound selected from dihetaryrylene compounds (IV; dihetarylethenes), scrimidide compounds (V; fylgimides), and mixtures thereof.

The benzothiazolene spiropyran compound (II) exhibits photochromic conversion represented by the following reaction formula (1).

Scheme 1

In Scheme (1), R represents a hydrogen atom, alkyl, aryl, aralkyl or alkylaryl. "Alkyl" refers to an alkyl group having 1 to 30 carbon atoms, preferably an alkyl group having 1 to 20 carbon atoms, which may be a linear, branched, or cyclic alkyl group. "Aryl" refers to an aryl group having 6 to 10 carbon atoms, such as a phenyl group and a naphthyl group. "Aralkyl" refers to an aralkyl group having 7 to 20 carbon atoms, such as a benzyl group. "Alkylaryl" refers to an alkylaryl group having 7 to 20 carbon atoms, such as methylphenyl group, methylnaphthyl and the like.

Table 1 below shows the spectroscopic-kinetic properties of the photochromic conversion of the benzothiazolene spiropyran compound (BSTP) in the photopolymerizable composition according to one embodiment of the present invention.

[Table 1]

compound
R
Spectroscopy of photoinduced structures
characteristic
λ _max , (nm) Of thermal bleaching of photoinduced structures
Reaction rate constant
k × 10 ³ , (c ^-1 ) BTSP 1 C ₁₆ H ₃₃ 580 2.9 BTSP 2 C ₆ H ₅ 610 6.1 BTSP 3 β-naphthol 605 9.0 BTSP 4 C ₃ H ₇ 572 5.2

The phenoxynaphthacequinone compound (III) shows photochromic conversion represented by the following reaction formula (2).

Scheme 2

In Scheme (2), R ₁ , R ₂ , R ₃ are each independently selected from the group consisting of hydrogen atom, alkyl, aryl, aralkyl and alkylaryl. "Alkyl" refers to an alkyl group having 1 to 30 carbon atoms, preferably an alkyl group having 1 to 20 carbon atoms, which may be a linear, branched, or cyclic alkyl group. "Aryl" refers to an aryl group having 6 to 10 carbon atoms, such as a phenyl group and a naphthyl group. "Aralkyl" refers to an aralkyl group having 7 to 20 carbon atoms, such as a benzyl group. "Alkylaryl" refers to an alkylaryl group having 7 to 20 carbon atoms, such as methylphenyl group, methylnaphthyl and the like.

Table 2 below shows the structure and spectroscopic-kinetic properties of photochromic phenoxynaphthacequinone (PNC) derivatives in photopolymerizable compositions according to aspects of the present invention.

TABLE 2

compound rescue Spectroscopic Characteristics of Photoinduced Structures
λ _max , (nm) Of thermal bleaching of photoinduced structures
Reaction rate constant
k × 10 ⁸ , (c ^-1 )


PNC 1

453
480


1.0


PNC 2

447
478


1.1

The dihetharylethene compound (IV) in the above thermally irreversible photochromic compound exhibits photochromic conversion represented by the following reaction formula (3).

Scheme 3

In Scheme (3), R ₁ , R ₄ represent a pentagonal or hexagonal fused heterocycle containing at least one hetero atom selected from N, S, and O, or a fused C6-C10 aryl group; R ₂ and R ₃ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms; And X represents S, O, NH, NR (R is an alkyl group having 1 to 10 carbon atoms). The Y portion enclosed by the wavy line in the formula (IV) is at least one hetero atom selected from N, S, and O in the skeleton of the cyclopentene ring and cyclopentene ring as shown in DHE 1 and DHE 2 of Table 3 below. Indicates to include. Examples of the fused heterocycle of R ₁ and R ₄ include a thiophene ring, a piperidine ring, a pyrrole ring, and the like as indicated in DHE 1 and DHE 2 below.

Table 3 below shows the structure and spectroscopic characteristics of the photochromic dihetharylethene derivative (DHE) in the photopolymerizable composition according to aspects of the present invention.

[Table 3]

compound rescue Of mineral induced structure
Spectroscopic properties
λ _max , (nm)





DHE 1

510




DHE 2

520





DHE 3

420
560
600

The handwritten mid compound (V; fylgimides) in the above-mentioned thermally irreversible photochromic compound exhibits photochromic conversion represented by the following reaction formula (4).

Scheme 4

In Scheme (4), Ar represents a pentagonal or hexagonal heterocyclic group containing at least one hetero atom selected from N, S, and O, or an aryl group having 6 to 10 carbon atoms; R ₁ , R ₂ and R ₃ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms; And X represents S, O, NH, and NR (R represents an alkyl group having 1 to 10 carbon atoms, or -NHCO ₂ R ₄ , wherein R ₄ represents a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms). do. In the closed photoinduced structure shown on the right side of Scheme (4), the Ar portion surrounded by the wavy line represents the remaining portion of Ar defined above.

Table 4 below shows the structure and spectroscopic characteristics of the photochromic handwriting derivative (FGM) in the photopolymerizable composition according to aspects of the present invention.

[Table 4]

compound rescue Of mineral induced structure
Spectroscopic properties
λ _max , (nm)




FGM 1

520

Said photosensitizer may be used independently, or may be used in combination of 2 or more. In the composition according to one embodiment of the present invention, the content of the photosensitizer may be about 0.05 to 5.0% by weight.

The co-initiator constituting the photoinitiator system in the composition according to the aspect of the present invention together with the photochromic sensitizer is activated by visible light together with the photochromic compound having the photoinduced structure in the presence of a photopolymerizable monomer. The photopolymerizable monomer is photopolymerized. Visible light that can be used in the present invention may be, for example, laser light having a wavelength of 400-650 nm, such as He-Ne (633 nm), Ar (515 nm, 488 nm), YAG (532 nm), He-Cd (442 nm) and the like.

The disclosure reagents that may be usefully used in the present invention may be selected from those known in the art, and more particularly, may be selected from known electron donor publications. Specific examples include N-phenylglycine, N, N-dialkylaniline compounds, tertiary amine compounds, organoborate salts, and the like. Specific examples of the N, N-dialkylaniline compound include 4-cyano-N, N-dimethylaniline, 4-bromo-N, N-dimethylaniline, 4-acetyl-N, N-dimethylaniline, 4-methyl -N, N-dimethylaniline, 4-amino-N, N-dimethylaniline, 4-ethoxy-N, N-dimethylaniline, 3-hydroxy-N, N-dimethylaniline, N, N, N ', N'- tetramethyl- 1, 4- dianiline, 2, 6- diethyl-N, N-dimethylaniline, pt- butyl-N, N- dimethylaniline, etc. are mentioned. Specific examples of the tertiary amine compound include triethylamine, dimethylethanolamine (DMEA), triethanolamine (TEA), triisopropanolamine, and the like. In addition, 2,2-dimethoxy-2-phenylacetophenone dimethylbenzyl ketal (DMBP) (Irgacure 651) may also be usefully used. These open reagents may be used alone or in combination of two or more thereof. In the composition of the present invention, the content of the open reagent may be about 0.2 to 6.0% by weight.

The polymerizable compound used in the composition according to one aspect of the present invention is a polymerizable compound containing at least one unsaturated double bond that can be polymerized by a radical mechanism. These polymerizable compounds include both monomers containing one or more ethylenically unsaturated bonds such as vinyl groups, allyl groups and polymers containing terminal or pendant ethylenically unsaturated bonds. Such compounds are well known in the art and include acrylic and methacrylic esters of polyhydric alcohols such as trimethylolpropane, pentaerythritol, and the like; Acrylate or methacrylate terminated epoxy resins; And acrylate or methacrylate terminated polyester and the like.

Additional examples of the polymerizable compound include butyl methacrylate, cyclohexyl methacrylate, ethylene glycol diacrylate, ethylene glycol dimethacrylate, trimethylolpropane triacrylate (TMPTA); Pentaerythritol trimethacrylate, pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, dipentaerythritol trimethacrylate, dipentaerythritol hydroxypentacacrylate (DPHPA), hexanediol-1, 6-dimethacrylate, diethylene glycol dimethacrylate, α, ω-bis (methacryloyloxyethyleneoxycarbonyloxy) ethyleneoxyethylene (OKM-2), bisphenol-A dimethacrylate, Bisphenol-A ethoxylate diacrylate, bisphenol-A ethoxylate dimethacrylate, bisphenol-A bis (glycidyldimethacrylate) (bisGMA), bisphenol-A glycerol diacrylate, bisphenol-A glycerol Late Dimethacrylate, Bisphenol-A Propoxylate Glycerate, Glycerol Diacrylate, Glycerol Dimethacrylate, Glycerol Triacrylate, Glycerol It comprises a roll trimethacrylate (TMG), N- vinylpyrrolidone (VP), 9- vinylcarbazole, glycidyl methacrylate, or mixtures thereof.

These polymerizable compounds may be used alone or in combination of two or more thereof. In the composition of the present invention, the content of the polymerizable compound may be 1.0 to 99.9% by weight.

The polymer binder used in the photopolymerizable composition according to one embodiment of the present invention is used to suppress the fluidity of the photopolymerizable composition according to the present invention and is not involved in the photopolymerization reaction. That is, this binder allows good hologram recording to be made by suppressing the fluidity of the composition of the present invention, which is located between the transparent substrate and the protective film during hologram recording.

Examples of the polymer binder that can be used in the present invention include vinyl polymers including polyvinylacetate, polyvinyl chloride and the like; Acrylate polymers including polymethyl acrylate, polyethyl acrylate and the like; Methacrylate polymers including polymethyl methacrylate (PMMA), polyethyl methacrylate, and the like. Of these, PMMA is preferably used to obtain holograms with high heat resistance, high transparency, high sensitivity, and high diffraction efficiency of the recording medium.

These polymer binders may be used alone or in combination of two or more thereof. In the photopolymerizable composition according to an aspect of the present invention, the content of the polymer binder may be about 0 to 97.5 wt%.

The plasticizer used in the composition according to one aspect of the present invention functions as a component for adjusting the viscosity and compatibility of the composition of the present invention and also for promoting separation of the polymer binder and the polymerizable compound during hologram recording. This plasticizer is a non-reactive compound with a polymeric binder and a polymeric compound. Examples of plasticizers that can be used in the compositions of the present invention include phthalate-based compounds such as dimethyl phthalate, diethyl phthalate, dibutyl phthalate (DBP), diethylhexyl phthalate, dioctyl phthalate; Esters of aliphatic dibasic acids such as dimethyl adipate, dibutyl adipate, dimethyl sebacate, diethyl sebacate, dibutyl sebacate, diethyl succinate; Phosphate compounds such as trimethylphosphate, triethyl phosphate, triphenyl phosphate, triglycidyl phosphate; Acetate compounds including glyceryl triacetate, 2-ethylhexyl acetate; Phosphite compounds such as tripetyl phosphite and dibutylhydrodiene phosphite; Alkylene glycol alkyl ethers such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether and diethylene glycol dimethyl ether; Low molecular weight polyethylene glycol; Silicone oils and the like.

These plasticizers may be used independently, or may be used in combination of 2 or more. In the composition according to one aspect of the invention, the content of the plasticizer may be 0 to 6.0% by weight.

The photopolymerizable composition according to an aspect of the present invention may further include additives such as thickeners, thermal polymerization inhibitors, chain transfer agents, solvents, and the like, as required in the art.

The solvent of high refractive index plays a role of improving the film formability in addition to viscosity adjustment and compatibility control of each component. Examples of solvents that may be used in the composition according to one aspect of the invention include acetone, benzene, toluene, xylene, methylethylketone, tetrahydrofuran, methylene dichloride, dichloromethane, chloroform, halogenated benzene, halogenated benzene, halogenated toluene , Or mixtures thereof. Among them, bromobenzene (BB), chlorobenzene, bromotoluene, chlorotoluene, and the like containing halogen atoms that contribute to high refractive index such as chlorine and bromine are preferable.

These solvents may be used alone or in combination of two or more thereof. In the composition of the present invention, the content of the solvent may be about 0 to 3.0% by weight.

Next, the preparation method of the photopolymerizable composition which concerns on one aspect of this invention is demonstrated.

At least one photo-sensitizer selected from the photochromic compound, the present initiator, the polymerizable compound, the polymer binder, the plasticizer, and optional components which can be mixed as necessary as described above are placed in a container such as a beaker and stirred. In this case, in order to promote dissolution of the solid component, it may be heated within a range where no modification of the composition occurs.

Next, a method for producing a photopolymerizable recording medium using the photopolymerizable composition according to one aspect of the present invention will be described.

When the photopolymerizable composition of the present invention is coated on a transparent substrate to form a photosensitive layer for recording, a photopolymerizable recording medium having a duplex structure composed of the transparent substrate and the photosensitive film can be obtained. Coating may be performed using various methods such as gravure coating, roll coating, bar coating, spin coating and the like. If necessary, by laminating a film, sheet or plate protective film on the photosensitive film, a photopolymerizable recording medium having a three-layer structure can be obtained. It is preferable to use a solvent in preparing the composition of the present invention. In this case, a solution or suspension obtained by dissolving or suspending at least one photo-sensitizer selected from the photochromic compound, a public reagent, a polymerizable compound, a polymer binder, a plasticizer, and optional components mixed as necessary in a solvent is prepared on a transparent substrate. The photosensitive film for recording is then formed by evaporating the solvent. When laminating | stacking a protective film on a photosensitive film | membrane, it is preferable to remove a solvent in advance before laminating | stacking a protective film. The thickness of the photosensitive film after solvent removal may be 1 to 200 μm.

The transparent substrate may be an optically transparent material such as a plastic plate or film such as a glass plate, a PET plate or film, a polycarbonate plate or film, a polymethyl methacrylate plate or film. The thickness of the transparent substrate may be 0.01 ~ 10mm. The transparent substrate is generally flat, but may be curved or have a concave-convex structure on the surface if necessary. The protective film may be made of an optically transparent material like the transparent substrate. The protective film may have a thickness of 0.01 to 10 mm.

Next, a method of holographic recording on a photopolymerizable recording medium according to an aspect of the present invention will be described. First, the photopolymerizable recording medium according to one aspect of the present invention is irradiated with non-coherent UV light on the photosensitive film of the recording medium to convert the photochromic compound into a colored form. Subsequently, the photosensitive film is irradiated with the interference fringe obtained by the interference of the coherent visible light laser light. For example, the interference fringe is obtained by spectroscopy coherent laser light into two beams of a reference beam and an object beam with a beam splitter or the like, and recombine the reference light and the object light by a mirror or the like. Can lose. Alternatively, this interference fringe can also be obtained by reflecting one laser light by a mirror. As a result, free radicals are produced in the presence of colored forms of photochromic compounds and co-initiators, which photopolymerize the photopolymerizable compounds and record the interference fringes in the photosensitive film as differences in refractive index. In this case, the difference in the refractive index is generated by the difference in the degree of photopolymerization according to the difference in the intensity of the light rays of the interference fringe.

The hologram recording recorded on the recording medium according to an aspect of the present invention can be reproduced by irradiating only the reference light to the recording medium. The hologram can be reproduced by the interference fringe diffraction of the reference light. Such hologram reproducing methods are well known in the art, and thus detailed descriptions thereof will be omitted.

When using the composition according to one aspect of the invention there is no need for a UV light source or heating element other than the laser beam in the visible region as described above. In other words, it is sufficient to irradiate the photopolymerizable recording medium with short-time radiation of incoherent UV light before hologram recording. After the hologram recording is completed by the short-time coherent visible light absorption effect of the photochromic compound, the medium is desensitized. Therefore, this reduces the cost of the recording apparatus and increases the resolution capability of the recording medium.

In addition, when the composition according to one aspect of the present invention includes 2-dimethoxy-2-phenylacetophenone dimethylbenzyl ketal (Irgacure 651) as a public reagent, photocuring of the photosensitive film may occur.

Hereinafter, the photopolymerizable composition of the present invention will be described in more detail with reference to Examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

Example  One

A photopolymerizable recording medium was produced as follows. First, a solution of photochromic phenoxynaphthacequinone in N-vinylpyrrolidone was separately prepared. The polymerizable compound OKM-2 and TMPTA and the open reagent DMEA were added into the solution and the solution was mixed uniformly. The mixed solution was evacuated for 20 minutes to remove air bubbles from the solution. The degassed solution was cast on a polyethylene terephthalate (PET) film (trade name: Lavsan film) having a spacer of 200 mu m thickness to form a photosensitive film for recording. Another PET film (Lavsan film) was coated on this photosensitive film to obtain a recording medium having a three-layer structure.

Thus, Table 5 shows the components and contents of the photopolymerizable composition (Sample 1) used to form the photosensitive film of the recording medium.

The photoinduced change in refractive index of the photosensitive film, which determines the recordability of the phase hologram on the photosensitive film by using a refractometer (IRF-22, Russia), was measured as follows. A few drops of sample were placed on the surface of the refractometer test prism using a glass rod, and then the refractive index of the initial solution was measured. Subsequently, a photosensitive film located between the prisms was irradiated with UV light of a lamp (DRS-250) through a color filter UFS-6 (λ = 366 nm) for 1 minute to give the photochromic compound a colorless form from a colorless form. Converted. The refractive index of this coloring solution (photosensitive film) was measured. The coloring solution was then irradiated with visible light (λ> 400 nm) emitted from an OI-18 lighter for 5 minutes. Then its refractive index was measured. The photopolymerization efficiency of the photosensitive film under visible light exposure was measured from the refractive index difference ( ^Δn = n ^vis -n ^UV ) after film irradiation with UV light and film irradiation with visible light.

In the case of sample 1, the light induction change value (Δn) of the refractive index was 0.0020. This demonstrates the possibility of recording a phase hologram on a recording medium prepared using the photopolymerizable composition (Sample 1) according to one aspect of the present invention.

Example  2

Using the same method as described in Example 1, a photopolymerizable composition (Sample 2) having the ingredients and contents shown in Table 5 was prepared.

The photoinduced change in refractive index of Sample 2 measured according to the method described in Example 1 is listed in Table 5. This data demonstrates the possibility of recording phase holograms using sample 2.

Example  3

A photopolymerizable composition (sample 3) of the components and contents shown in Table 5 was prepared using the same method as described in Example 1 except that bromobenzene (BB) was used as the solvent instead of the polymerizable compound VP. .

The photoinduced change in refractive index of Sample 3 measured according to the method described in Example 1 is listed in Table 5. This data demonstrates the possibility of recording phase holograms using sample 3.

TABLE 5

Sample
number Photochromic
compound
(weight%) Open Tense,
(weight%) Polymerizable compound
(weight%) Non-synthetic
menstruum
(weight%) Refractive
Mineral induction
change
^Δn = n ^vis -n ^UV DMEA TEA OKM-2 TMPTA VP BB One PNC 1 (0,25) 2.33 - 89.10 4.90 3.42 - 0.0020 2 PNC 1 (0.25) - 2.37 89.10 4.95 3.33 - 0.0045 3 PNC 1 (0.25) 2.28 - 89.77 4.99 - 2.71 0.0060

Example  4-6

Using the same method as described in Example 1, a photosensitive film was prepared using a composition comprising the components and contents shown in Table 6. These photoresist films include the UV photoinitiator DMBP as one of the open initiators. DMBP causes film photocuring by the effect of incoherent UV light. DMBP was added to the solution in the first step of sample preparation. The compositions and contents of these samples 4-6 are shown in Table 6.

The photoinduced change in refractive index measured according to the method described in Example 1 is also shown in Table 3. These data demonstrate that the photoresist can be photocured by UV rays used for the photoinduced change of the photosensitizer sensitive to visible light, and the phase hologram can be recorded by laser light in the visible wavelength range. do. Photocuring levels were evaluated by the difference in film refractive index (Δn = n ^UV −n ^init ) between the sample and the initial sample after UV irradiation.

TABLE 6

Sample number Photochromic
compound
(weight%) Open Tense,
(weight%) Polymerizable compound
(weight%) Refractive
Mineral induction
△ n DMEA DMBP OKM-2 TMPTA bis
GMA TGM VP Δn = n ^UV -n ^{init Δn} = n ^vis -n ^UV 4 PNC 1 (0.24) 2.18 0.41 88.90 4.94 - - 3.33 0.0107 0.0094 5 PNC 1 (0.41) 2.25 0.52 69.82 23.28 - - 3.72 0.0125 0.0025 6 PNC 1 (0.29) 2.35 0.40 - - 46.59 46.59 3.77 0.0148 0.0070

Example  7-20

Using the same method as described in Example 1, a photosensitive film containing the photochromic compound PNC 2 was prepared. These photoresist films include the UV photoinitiator DMBP as one of the open initiators. This photoinitiator causes film photocuring by the effect of incoherent UV light. Incoherent UV light was used to obtain the photoinduced form of the photochromic compound. DMBP was placed in the VP solution in the first step of sample preparation. The compositions and contents of these samples 7-20 are shown in Table 7.

Table 7 also shows the change in the light induction of the refractive index measured according to the same method as described in Example 1. These data demonstrate that the photoresist can be photocured by UV light used for the photoinduced change of the photosensitizer sensitive to visible light, and the phase hologram can be recorded by laser light in the visible wavelength range. do.

TABLE 7

Sample
number Photochromic
compound
(weight%) Open Tense,
(weight%) Polymerizable compound
(weight%) Refractive
Mineral induction
△ n DMEA TEA DMBP OKM-2 TMPTA bis
GMA VP
Δn = n ^UV -n ^{init Δn} = n ^vis -n ^UV 7 PNC 2
(0.24) 2.26 - 0.43 88.43 4.91 - 3.73 0.0015 0.0040 8 PNC 2
(0.23) 2.21 - 0.44 46.67 46.67 - 3.78 0.0015 0.0045 9 PNC 2
(0.22) 2.26 - 0.44 93.35 - - 3.73 0.0027 0.0060 10 PNC 2
(0.25) 2.16 - 0.52 - 93.24 - 3.83 0.0143 0.0012 11 PNC 2
(0.25) 2.22 - 0.46 86.76 4.82 - 5.49 0.0063 0.0072 12 PNC 2
(0.21) 2.14 - 0.39 82.94 4.47 - 10.85 0.0055 0.0095 13 PNC 2
(0.22) 1.19 - 0.49 89.36 4.96 - 3.78 0.0120 0.0060 14 PNC 2
(0.22) 5.24 - 0.38 85.69 4.76 - 3.71 0.0033 0.0070 15 PNC 2
(0.23) 2.33 - 1.27 87.56 4.86 - 3.75 0.0149 0.0030 16 PNC 2
(0.22) 2.15 - 5.09 84.30 4.68 - 3.56 0.0190 0.0030 17 PNC 2
(0.05) 2.35 - 0.63 88.33 4.91 - 3.73 0.0160 0.0010 18 PNC 2
(4.80) 2.16 - 0.35 84.36 4.67 - 3.66 0.0015 0.0025 19 PNC 2
(0.21) - 5.76 0.66 85.05 4.73 - 3.59 0.0130 0.0065 20 PNC 2
(0.29) 2.26 - 0.48 - - 93.24 3.73 0.0055 0.0105

Example  21-23

These films include the UV photoinitiator DMBP as one of the open initiators. This photoinitiator prepared a photosensitive film containing the photochromic compound PNC 2 by the same method as described in Example 1. Layer photocuring is caused by the effects of incoherent UV light. Incoherent UV light was used to obtain the photoinduced form of the photochromic compound. DMBP was placed in the VP solution in the first step of sample preparation. In addition, PMMA was added to the composition of the photopolymerizable medium as a polymer binder. For this purpose, a solution in which PMMA was dissolved in chloroform was placed in a VP solution containing a photochromic compound, a polymerizable compound, and the like. The sample was vacuumed to remove chloroform from the photochromic composition. The compositions and contents of these samples 21-23 are shown in Table 8. In Sample 23, a DBP plasticizer was further added into the PMMA solution.

Table 8 also shows the light inducement change of the refractive index measured according to the same method as described in Example 1. These data demonstrate that the photoresist can be photocured by UV light used for the photoinduced change of the photosensitizer sensitive to visible light, and the phase hologram can be recorded by laser light in the visible wavelength range. do.

[Table 8]

Sample
number Photochromic
compound
(weight%) Open Tense
(weight%) Polymerizable
compound
(weight%) bookbinder
(weight%) Plasticizer
(weight%) Refractive
Mineral induction
△ n DMEA DMBP OKM-2 VP
PMMA DBP Δn = n ^UV -n ^{init Δn} = n ^vis -n ^UV 21 PNC 2
(0.22) 2.25 0.55 46.61 3.74 46.62 - 0.0045 0.0093 22 PNC 2
(0.23) 2.16 0.51 - 3.83 97.23 - 0.0025 0.0050 23 PNC 2
(0.25) 2.20 0.50 - 3.73 92.13 5.0 0.0020 0.0045

Example  24-25

According to the same method as described in Example 1, using the photopolymerizable composition shown in Table 9 to prepare a photosensitive film comprising a photochromic compound BSTP. VP or BB was used as solvent. The compositions and contents of these samples 24 and 25 are shown in Table 9.

The photoinduced change in refractive index of the sample measured according to the same method as described in Example 1 is also described in Table 9. This data demonstrates the possibility of recording phase holograms using this sample.

TABLE 9

Sample
number Photochromic
compound
(weight%) Open Tense
(weight%) Polymerizable compound
(weight%) Non-synthetic
menstruum
(weight%) Refractive
Mineral induction change,
^Δn = n ^vis -n ^UV DMEA OKM-2 TMPTA VP BB 24 BTSP 1
(0.27) 2.33 89.58 4.97 2.99 - 0.0020 25 BTSP 1
(0.26) 2.19 89.59 4.98 - 2.98 0.0005

Example  26-44

Using the same method as described in Example 1, a photosensitive film including the photochromic compound BTSP was prepared. These films include the UV photoinitiator DMBP as one of the open initiators. This photoinitiator causes film photocuring by the effect of incoherent UV light. Incoherent UV light was used to obtain the photoinduced form of the photochromic compound. DMBP was placed in the VP solution in the first step of sample preparation. The compositions of these samples 26-44 are shown in Table 10. Table 10 also shows the change in photoinduction of the refractive index measured according to the same method as described in Example 1. These data demonstrate that the photoresist can be photocured by UV light used for the photoinduced change of the photosensitizer sensitive to visible light, and the phase hologram can be recorded by laser light in the visible wavelength range. do.

TABLE 10

Sample
number Photochromic
compound
(weight%) Open Tense
(weight%) Polymerizable compound
(weight%) Refractive
Mineral induction change,
△ n DMEA TEA DMBP
OKM-2 TMPTA bis
GMA TGM VP Δn = n ^UV -n ^{init Δn} = n ^vis -n ^UV 26 BTSP 1
(0.28) 2.18 - 0.54 89.10 4.95 - - 2.94 0.0042 0.0177 27 BTSP 1
(0.25) 2.31 - 0.49 - 23.98 69.85 - 3.82 0.0010 0.0160 28 BTSP 1
(0.28) 2.34 - 0.84 - - 46.39 46.39 3.76 0.0040 0.0145 29 BTSP 2
(0.44) 2.15 0.65 88.05 4.89 - - 3.82 0.0025 0.0060 30 BTSP 3
(0.25) 2.25 - 0.59 46.59 46.59 - - 3.73 0.0028 0.0048 31 BTSP 3
(0.24) 2.16 - 0.53 - 93.25 - - 3.82 0.0005 0.0005 32 BTSP 3
(0.27) 2.36 - 0.58 93.16 - - - 3.73 0.0020 0.0065 33 BTSP 3
(0.22) 2.13 - 0.68 82.20 4.84 - - 5.03 0.0015 0.0045 34 BTSP 3
(0.24) 1.99 - 0.56 81.56 4.53 - - 11.12 0.0030 0.0075 35 BTSP 3
(0.23) 1.09 - 0.47 89.46 4.97 - - 3.78 0.0005 0.0070 36 BTSP 3
(0.24) 4.76 - 0.57 85.75 4.76 - - 3.53 0.0010 0.0030 37 BTSP 3
(0.25) 2.17 - 0.13 88.87 4.93 - - 3.75 0.0003 0.0040 38 BTSP 3
(0.26) 2.17 - 4.85 84.55 4.69 - - 3.48 0.0078 0.0100 39 BTSP 3
(0.04) 2.36 - 0.46 88.40 4.91 - - 3.83 0.0025 0.0020 40 BTSP 3
(2.51) 2.21 - 0.58 86.76 4.79 - - 3.55 0.0015 0.0025 41 BTSP 3
(0.22) - 5.71 0.53 85.29 4.74 - - 3.51 0.0080 0.0010 42 BTSP 3
(0.24) 2.35 - 0.51 - - 93.17 - 3.73 0.0225 0.0080 43 BTSP 3
(0.28) 2.21 - 0.77 88.08 4.89 - - 3.77 0.0005 0.0055 44 BTSP 4
(0.28) 2.25 - 0.53 88.30 4.91 - - 3.73 0.0005 0.0170

Example  45-47

Using the same method as described in Example 1, a photosensitive film including the photochromic compound BTSP 3 was prepared. These films include the UV photoinitiator DMBP as one of the open initiators. This photoinitiator causes film photocuring by the effect of incoherent UV light. Incoherent UV light was used to obtain the photoinduced form of the photochromic compound. DMBP was placed in the VP solution in the first step of sample preparation. In addition, PMMA was added to the composition of the photopolymerizable medium as a polymer binder. To this end, a solution in which PMMA was dissolved in chloroform was placed in a VP solution containing a photochromic compound BTSP 3, a DMBP open reagent, and the like. The sample was vacuumed to remove chloroform from the photochromic composition. The compositions of these samples 45-47 are shown in Table 11.

The photoinduced change in refractive index measured according to the method described in Example 1 is also shown in Table 11. These data demonstrate that the photoresist can be photocured by UV light used for the photoinduced change of the photosensitizer sensitive to visible light, and the phase hologram can be recorded by laser light in the visible wavelength range. do.

TABLE 11

fountain
Play
time
number Photochromic
compound
(weight%) Open Tense
(weight%) Polymerizable
compound
(weight%) Plasticizer
(weight%) bookbinder
(weight%) Refractive
Mineral induction change,
△ n DMEA DMBP OKM-2 VP
DBP PMMA Δn = n ^UV -n ^{init Δn} = n ^vis -n ^UV 45 BTSP 3 (0.23) 2.25 0.66 46.57 3.72 - 46.57 0.0010 0.0105 46 BTSP 3 (0.29) 2.10 0.42 - 3.84 - 93.39 0.0060 0.0160 47 BTSP 3 (0.25) 2.25 0.59 - 3.73 4.12 89.27 0.0030 0.0135

Example  48-54

Using the same method as described in Example 1, a photosensitive film containing the photochromic compound DHE or FGM was prepared. These membranes include the UV photoinitiator DMBP as the open initiator, with the exception of Sample 48. This photoinitiator causes film photocuring by the effect of UV rays. Incoherent UV light was used to obtain the photoinduced form of the photochromic compound. DMBP was placed in the VP solution in the first step of sample preparation. The compositions of these samples 48-54 are shown in Table 12.

The photoinduced change in refractive index measured according to the method described in Example 1 is also shown in Table 12. These data demonstrate that the photoresist can be photocured by UV light used for the photoinduced change of the photosensitizer sensitive to visible light, and the phase hologram can be recorded by laser light in the visible wavelength range. do.

TABLE 12

fountain
Play
time
number Light side
Color
compound
(weight%) Open Tense
(weight%) Polymerizable compound
(weight%) Refractive
Mineral induction change,
△ n DMEA TEA DMBP OKM-2 TMPTA bis
GMA TGM VP Δn = n ^UV -n ^{init Δn} = n ^vis -n ^UV 48 DHE 1 (0.22) - 2.18 - 88.66 4.98 - - 2.96 0.0000 0.0100 49 DHE 1 (0.26) 2.33 - 0.70 89.02 4.98 - - 2.93 0.0075 0.0160 50 DHE 1 (0.48) 2.25 - 0.52 69.70 23.23 - - 3.82 0.0138 0.0035 51 DHE 1 (0.42) 2.31 - 0.50 - - 46.5 46.5 3.73 0.0005 0.0115 52 DHE 2 (0.24) 2.25 - 0.44 88.33 4.91 - - 3.83 0.0160 0.0045 53 DHE 3 (0.39) 2.16 - 0.49 88.26 4.91 - - 3.79 0.0019 0.0040 54 FGM 1 (0.26) 2.06 - 0.69 88.22 4.91 - - 3.79 0.0200 0.0020

Example  55

The hologram was recorded on the photopolymerizable recording medium prepared according to the method described in Example 22. The angular sensitivity of the hologram recording medium for determining the information capacity was changed as follows.

The photopolymerizable photosensitive film was placed between two PET films (Lavsan film) separated by a 0.5 mm thick polymer spacer. The central part thereof was cut and filled with the photopolymerizable composition. Prior to recording the hologram, the recording medium sample was irradiated with incoherent UV light emitted from the DRS-250 lamp for one minute through the color filter UFS-6 (λ = 366 nm). This resulted in the photochromic compound in the sample being converted to the colored form.

Holographic gratings were then recorded on the recording medium using coherent laser light (λ = 488 nm) emitted from an argon (Ar) laser at 5.5 mW / cm ² .

After recording the hologram grating, the sample was irradiated with visible light emitted from the OI-18 lighter to completely bleach the sample. The hologram grating was regenerated by irradiating interference light having a wavelength of 633 nm emitted from helium-neon (He-Ne). Radiation diffractions were recorded in real time using a photodetector located at the Bragg angle. The angle dependence of the diffraction efficiency was measured while changing the tilt angle of the recording and reproduction laser beam.

Fig. 1 shows a graph of diffraction efficiency versus angle when Ar laser light is irradiated to a grating in the recording medium at 5.5 mW / cm ² . Referring to Fig. 1, it can be seen that the diffraction efficiency of the recording medium is highly dependent on the angle (i.e., large angle selectivity), which is used for the manufacture of ultra-high information capacity three-dimensional optical memory. It shows what can be.

Example  56

A photopolymerizable recording medium was produced in the same manner as used in Example 55, except that a glass plate was used instead of the PET film to form the three-layer structure. The hologram grating was recorded on the recording medium using the method described in Example 55. Satisfactory results were obtained using this recording medium.

As described above, using the photopolymerizable composition according to one aspect of the present invention containing a new combination of photoinitiator systems, a photopolymerizable recording medium having a large angle selectivity of diffraction efficiency can be produced. In addition, this photopolymerizable recording medium can be effectively used for the manufacture of ultra-high information capacity three-dimensional hologram optical memory. According to one aspect of the present invention, post-exposure and heating are not required after hologram recording.

Although the invention has been described in detail based on exemplary embodiments, it will be understood by those skilled in the art that various changes may be made in form and detail without departing from the spirit and scope of the invention as defined by the following claims.

Claims (26)

1.0 to 99.9 wt% of at least one photopolymerizable compound; 0.05 to 0.5% by weight of at least one photosensiitizer selected from photochromic compounds exhibiting photochromic by non-coherent UV light; 0.2 to 6.0% by weight of a disclosure reagent which is activated by visible light in the presence of a photochromic compound having a photochromic structure to photopolymerize the photopolymerizable compound; 0 to 97.5 weight percent of a polymeric binder; Plasticizer 0-6.0 wt%; And It contains 0 to 3.0% by weight of non-polymerizable solvent, The photochromic compound is a phenoxynaphthacequinone compound: or A photopolymerizable composition, characterized in that selected from the group consisting of dihetarylethenes, handwritten mid compounds (fylgimides) and mixtures thereof. delete delete The polymerizable compound of claim 1, wherein the polymerizable compound is α, ω-bis (methacryloyloxyethylene oxycarbonyloxy) ethyleneoxyethylene (OKM-2), trimethylolpropane triacrylate (TMPTA), bisphenol-A Photopolymerizable composition, characterized in that it is selected from the group consisting of bis (glycidyldimethacrylate) (bisGMA), N-vinyl pyrrolidone (VP), glycerol trimethacrylate (TMG), and mixtures thereof. The photopolymerizable composition of claim 1, wherein the polymer binder is polymethyl methacrylate (PMMA). The method of claim 1, wherein the open reagent is selected from the group consisting of dimethylethanolamine (DMEA), triethanolamine (TEA), 2,2-dimethoxy-2-phenylacetophenone dimethylbenzyl ketal (DMBP), and mixtures thereof. Photopolymerizable composition, characterized in that. The photopolymerizable composition of claim 1, wherein the nonpolymerizable solvent is selected from the group consisting of halogenated benzene, halogenated toluene, and mixtures thereof. The photopolymerizable composition of claim 1, wherein the plasticizer is a phthalate compound. Transparent substrates; And A photopolymerizable recording medium comprising a photosensitive layer laminated as a recording layer on the transparent substrate, The photosensitive film, 1.0 to 99.9 wt% of at least one photopolymerizable compound; 0.05 to 0.5% by weight of at least one photosensiitizer selected from photochromic compounds exhibiting photochromic by non-coherent UV light; 0.2 to 6.0% by weight of a disclosure reagent which is activated by visible light in the presence of a photochromic compound having a photochromic structure to photopolymerize the photopolymerizable compound; 0 to 97.5 weight percent of a polymeric binder; Plasticizer 0-6.0 wt%; And It contains 0 to 3.0% by weight of non-polymerizable solvent, The photochromic compound is a phenoxynaphthacequinone compound: or A photopolymerizable recording medium, characterized in that selected from the group consisting of dihetarylethenes, handwritten mid compounds, and mixtures thereof. delete delete The method of claim 9, wherein the polymerizable compound is α, ω-bis (methacryloyloxyethyleneoxycarbonyloxy) ethyleneoxyethylene (OKM-2), trimethylolpropane triacrylate (TMPTA), bisphenol-A Photopolymerizable recording media, characterized in that selected from the group consisting of bis (glycidyldimethacrylate) (bisGMA), N-vinyl pyrrolidone (VP), glycerol trimethacrylate (TMG), and mixtures thereof . 10. The photopolymerizable recording medium of claim 9, wherein the polymer binder is polymethyl methacrylate (PMMA). The method of claim 9, wherein the co-initiator is selected from the group consisting of dimethylethanolamine (DMEA), triethanolamine (TEA), 2,2-dimethoxy-2-phenylacetophenone dimethylbenzyl ketal (DMBP), and mixtures thereof. A photopolymerizable recording medium, characterized in that selected. 10. The photopolymerizable recording medium of claim 9, wherein the nonpolymerizable solvent is selected from the group consisting of halogenated benzene, halogenated toluene, and mixtures thereof. 10. The photopolymerizable recording medium of claim 9, wherein the plasticizer is a phthalate compound. 10. The photopolymerizable recording medium according to claim 9, wherein a protective film is further provided on the photosensitive film. 18. The photopolymerizable recording medium of claim 17, wherein the transparent substrate and the protective film are transparent polymer films. 10. The photopolymerizable recording medium of claim 9, wherein the photopolymerizable recording medium is a hologram memory. A method of recording a hologram on a photopolymerizable recording medium according to claim 9, Irradiating non-coherent UV light on the photosensitive film of the recording medium to convert the photochromic compound into a colored form; And Irradiating the photosensitive film with an interference fringe of a reference beam and an object beam split from the coherent visible light laser light, the photochromic compound of the colored form and the presence of the open reagent And photopolymerizing the photopolymerizable compound using free radicals to record the interference fringe on the photosensitive film as a difference in refractive index. 21. The hologram recording method of claim 20, wherein the difference in refractive index is generated by a difference in degree of polymerization which varies with the intensity of light irradiated onto the interference fringe. A hologram reproducing method recorded on a polymerizable recording medium according to claim 9, And reproducing reference light on the recording medium. The photopolymerizable composition of claim 1, wherein the visible light has a wavelength of 400-600 nm. 10. The photopolymerizable recording medium of claim 9, wherein the visible light has a wavelength of 400-600 nm. The method of claim 9, wherein the photosensitive film further comprises an additive, wherein the photosensitizer, the open reagent, the polymerizable compound, the polymer binder, and the additive is heated to a temperature range that does not cause denaturation Photopolymerizable recording medium. 21. The hologram recording method according to claim 20, wherein after recording the hologram, no post-exposure and heating steps are required.

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