JPH06194632A - Liquid crystal device and its production - Google Patents

Abstract

PURPOSE:To obtain a liq. crystal device having a low driving voltage and a high contrast, with the improved temp. characteristic and without need for a polarizing plate by using a transparent high molecular substance having bromine atom or chlorine atom in the device with a light controlling layer contg. a liq. crystal material and a transparent high molecular substance. CONSTITUTION:The light controlling layer contains a liq. crystal material and the transparent high molecular substance. The transparent high molecular substance is obtained by polymerizing a polymerizable composition contg. a polymerizable compd. having bromine atom or chlorine atom, i.e., a (meth)acrylic derivative having bromine atom or chlorine atom. When the device is produced, a light-controlling layer forming material consisting of a liq. crystal material, a polymerizable composition contg. a (meth)acrylic derivative having bromine atom or chlorine atom, a polymerization initiator, a chain transfer agent as an optional component, a photosensitizer, etc., is held between two substrates at least one of which is transparent, and polymerization energy is supplied to polymerize and cure the composition.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal device capable of forming a large area and a method for manufacturing the same, and more specifically, it electrically shields and opens a visual field, and limits, blocks, and transmits light or illumination light. That can be operated,
It is used as a screen for blocking the field of view in building windows and show windows, and as a curtain for daylighting control. It also displays characters and figures, and electrically switches the display with high-speed response to display OA equipment. The present invention relates to a liquid crystal device used as a display device such as a high information display body, an advertisement board, a guide board, a decorative display board, etc.

[0002]

2. Description of the Related Art Conventionally, liquid crystal devices are TN (twisted nematic) type and S type using nematic liquid crystals.
A TN (super twisted nematic) type has been put into practical use. Also, a liquid crystal device using a ferroelectric liquid crystal has been proposed.

However, these require a polarizing plate and also require an alignment treatment.

On the other hand, as a method of manufacturing a large-sized and inexpensive liquid crystal device which does not need them and has a bright contrast, liquid crystal droplets are dispersed in a polymer by encapsulating liquid crystal, and the polymer is formed into a film. The method is known. Here, gelatin, gum arabic, polyvinyl alcohol and the like have been proposed as encapsulating substances (Japanese Patent Publication No. 58-501631 and US Pat. No. 4,435,047).

In the technology disclosed in the above specification,
Liquid crystal molecules encapsulated in polyvinyl alcohol are
If it has a positive dielectric anisotropy in the thin layer, the liquid crystal molecules are aligned in the direction of the electric field in the presence of an electric field, and the refractive index n _{o of the} liquid crystal and the refractive index n _{p of the} polymer are When they are equal, transparency is developed. When an electric field is removed, the liquid crystal molecules are returned to the random sequence, the refractive index of the liquid crystal droplets is deviated from the n _o, the liquid crystal droplets scatter light at the boundary surface, since blocking the transmission of light, Ususotai Becomes cloudy.

As described above, there are some known techniques for forming a thin film of a polymer in which encapsulated liquid crystals are encapsulated. For example, Japanese Patent Publication No.
No. 502128, one dispersed in a liquid crystal epoxy resin, and one disclosed in Japanese Unexamined Patent Publication No. 62-2231, one in which a liquid crystal is dispersed in a special UV-curable polymer.
No. 1233 discloses a technique in which a dimming layer is formed in a solution of a photocurable vinyl compound and a liquid crystal by utilizing phase separation of a liquid crystal substance accompanying photocuring of the photocurable vinyl compound. It is disclosed.

Further, in order to enable low-voltage driving characteristics, high contrast, and time-division driving, which are important characteristics required for practical use of liquid crystal devices, JP-A-1-198725.
The publication discloses a technique in which a polymer is formed into a three-dimensional network structure in a continuous layer of a liquid crystal material to enable low voltage driving of a liquid crystal device.

[0008]

However, a liquid crystal device including a liquid crystal and a polymer, including a liquid crystal device having a light control layer formed by forming a polymer having a three-dimensional network structure in a continuous layer of a liquid crystal material. In this case, the driving voltage is required to be 10 V or more, and it is extremely difficult to use an IC driver for driving a liquid crystal device which is currently widely used.

Further, even when it can be driven at 5 V or less, there is a practical problem with respect to the temperature characteristic that the driving voltage at each of the low temperature and the high temperature greatly changes.

The problem to be solved by the present invention is to provide a conventional large-sized liquid crystal device which has a low driving voltage, a high contrast, improved temperature characteristics, and does not require a polarizing plate, and a manufacturing method thereof. To provide.

[0011]

The inventors of the present invention have made extensive studies in order to solve the above problems, and as a result, arrived at the present invention.

That is, in order to solve the above-mentioned problems, the present invention has two substrates, at least one of which has an electrode layer and is transparent, and a light control layer supported between these substrates. A liquid crystal device in which a layer contains a liquid crystal material and a transparent polymer substance, wherein the transparent polymer substance has a bromine atom or a chlorine atom.

Further, the transparent polymer material contains a polymerizable composition containing a polymerizable compound having a bromine atom or a chlorine atom, and more specifically, a (meth) acrylate derivative having a bromine atom or a chlorine atom. There is provided a liquid crystal device characterized by being obtained by polymerizing the polymerizable composition.

The substrate used in the present invention may be a rigid material such as glass or metal, or a flexible material such as a plastic film. The two substrates are opposed to each other and are separated by an appropriate distance, at least one of which has transparency, and a liquid crystal layer and a transparent polymer substance layer sandwiched between the two substrates. The light control layer consisting of must be visible from the outside world. However, complete transparency is not essential.

If the liquid crystal device is used to act on light passing from one side of the device to the other, the two substrates will both be suitably transparent. . Appropriate transparent or opaque electrodes may be provided on the entire surface or a part of the substrate depending on the purpose. However, in the case of a flexible material such as plastic, it can be used for the liquid crystal device of the present invention after being fixed to a rigid material such as glass or metal.

Further, a spacer for holding a space can be usually provided between the two substrates, as in the well-known liquid crystal device.

As the spacer, for example, Mylar,
Alumina, rod-type glass fiber, glass beads, polymer beads, and other various liquid crystal cells can be used.

The liquid crystal material used in the present invention does not need to be a single liquid crystal compound, and may be a mixture containing two or more kinds of liquid crystal compounds or substances other than the liquid crystal compounds. Any material generally recognized as a liquid crystal material in this technical field may be used, and one having a positive dielectric anisotropy is preferable.

The liquid crystal used is preferably a nematic liquid crystal, a smectic liquid crystal or a cholesteric liquid crystal, and a nematic liquid crystal is particularly preferable. In order to improve the performance, a cholesteric liquid crystal, a chiral nematic liquid crystal, a chiral smectic liquid crystal or the like, or a chiral compound may be appropriately contained.

The liquid crystal material used in the present invention is preferably a blended composition comprising one or more compounds selected from the compound group shown below, and the characteristics of the liquid crystal material, that is, the phase of the isotropic liquid and the liquid crystal. Use appropriately selected and blended for the purpose of improving the transition temperature, the melting point, the viscosity, the refractive index anisotropy (Δn), the dielectric anisotropy (Δε), the solubility with the polymerizable composition and the like. You can

Examples of the liquid crystal material include 4-substituted benzoic acid 4'-substituted phenyl ester, 4-substituted cyclohexanecarboxylic acid 4'-substituted phenyl ester, 4-substituted cyclohexanecarboxylic acid 4'-substituted biphenyl ester, 4- (4-substituted cyclohexanecarbonyloxy)
Benzoic acid 4'-substituted phenyl ester, 4- (4-substituted cyclohexyl) benzoic acid 4'-substituted phenyl ester, 4- (4-substituted cyclohexyl) benzoic acid 4'-substituted cyclohexyl ester, 4-substituted 4'-substituted Biphenyl, 4-substituted phenyl 4'-substituted cyclohexane, 4
-Substituted 4 "-substituted terphenyl, 4-substituted biphenyl 4'-substituted cyclohexane, 2- (4-substituted phenyl)
A 5-substituted pyrimidine etc. can be mentioned.

The content of the liquid crystal material in the light control layer forming material is
The range of 60 to 95% by weight is preferable, and 70 to 90% by weight
Is particularly preferred.

The transparent polymer substance formed in the light control layer may be one in which the liquid crystal material is spherically dispersed in the polymer, but one having a three-dimensional network structure is more preferable.

It is preferable that the transparent polymer material is filled with a liquid crystal material in the three-dimensional network portion, and the liquid crystal material forms a continuous layer. By forming a disordered state of the liquid crystal material, It is effective in forming a boundary surface and expressing light scattering.

The transparent polymer substance is not limited to a solid substance, and may have flexibility, flexibility, and elasticity as long as it is suitable for the purpose.

The liquid crystal device of the present invention can be manufactured, for example, as follows.

That is, (1) a liquid crystal material, between at least one substrate having an electrode layer and at least one of which is transparent,
(2) A polymerizable composition containing a (meth) acrylate derivative having a bromine atom or a chlorine atom, (3) a polymerization initiator, and (4) an optional component, a chain transfer agent, a photosensitizer, a dye, and a crosslinker. A liquid crystal device having a light control layer composed of a liquid crystal material and a transparent polymer substance by sandwiching a light control layer forming material composed of an agent and the like, supplying energy for polymerization, and polymerizing and curing the polymerizable composition. Can be manufactured.

In order to sandwich the light control layer forming material between the two substrates, this light control layer forming material may be injected between the substrates, but a suitable solution coater or spin coater may be provided on one of the substrates. You may apply | coat uniformly using the etc., and then superimpose and press-bond the other board | substrate.

Further, the light control layer forming material is applied to one of the substrates to a uniform thickness, the energy for polymerization is supplied to polymerize and cure the polymerizable composition to form the light control layer, and then the other. The method of manufacturing a liquid crystal device in which the substrates of (1) and (2) are bonded together is also effective.

The energy for polymerization may be any energy as long as the liquid crystal material and the transparent polymer substance are appropriately dispersed or an appropriate three-dimensional network structure is formed, and examples thereof include ultraviolet rays and visible rays. , Radiation such as electron beams, heat, and the like.

The photopolymerization method using ultraviolet rays is particularly preferable. Ultraviolet rays and visible rays that have been cut in the short wavelength region are particularly preferable for improving the durability of the device.

Irradiation with ultraviolet rays while maintaining the uniform liquid state of the material for forming a light control layer is preferable for forming a light control layer having a uniform particle distribution or a network structure.

In order to polymerize the photopolymerizable composition in the liquid crystal material, light irradiation intensity and irradiation amount of a certain intensity or more are required, which is the reactivity of the photopolymerizable composition and the photopolymerization initiator. The formation of a three-dimensional mesh structure and the size of the mesh can be made uniform by selecting an appropriate light intensity depending on the type and density of the mesh.

More preferably, as the light irradiation method,
Irradiating the photopolymerizable composition interposed between the substrates with a temporally and planarly uniform irradiation is effective in instantaneously irradiating the photopolymerizable composition with strong light to promote polymerization, thereby making the size of the mesh uniform. Target.

That is, it is possible to form a transparent polymer substance having a uniform three-dimensional network structure in a liquid crystal layer by irradiating ultraviolet rays in a pulsed manner at an appropriate intensity,
As a result, the obtained liquid crystal device has a clear threshold voltage and steepness, and time-division driving becomes possible.

The polymerizable composition used in the present invention contains a (meth) acrylate derivative having a bromine atom or a chlorine atom, and may further contain a polymer-forming monomer or oligomer as an optional component. Good.

Having a bromine atom or a chlorine atom (meth)
Good temperature characteristics can be obtained by using an acrylate derivative, and the higher the number of atoms, the more the temperature characteristics tend to be improved. The content of bromine atom or chlorine atom is preferably 0.5% by weight or more, and more preferably 1% by weight or more and 50% by weight or less.

When comparing various characteristics such as temperature characteristics, the (meth) acrylate derivative having a bromine atom is more preferable than the chlorine atom.

Further, the polymer substance obtained by polymerizing the (meth) acrylate derivative having a bromine atom or a chlorine atom is often a compound having a larger refractive index than general polymer substances,
The refractive index characteristics of the transparent polymer material relating to the transmittance characteristics in the device of the present invention can be arbitrarily adjusted,
It is useful.

Examples of the (meth) acrylate having a bromine atom or a chlorine atom used in the present invention include, as a substituent, propyl, butyl, amyl, 2-ethylhexyl, octyl, nonyl, dodecyl, hexadecyl, butoxyethyl, cyclohexyl, Acrylate or methacrylate having a group such as cyclopentyl, norbornyl, bicycloheptane norbornyl, bicyclopentenyl, tricyclodecanyl, and cholesteryl, a compound in which one or more hydrogen atoms in the alkyl chain of the acrylate or methacrylate is replaced by a bromine atom or a chlorine atom, phenyl, phenoxy , A compound in which one or more hydrogen atoms in an aromatic ring of an acrylate or a methacrylate having an aromatic skeleton such as biphenyl or bisphenol A are replaced with a bromine atom or a chlorine atom.

It is preferable that the polymerizable composition contains a monofunctional (meth) acrylate derivative in order to achieve low voltage driving, and the proportion thereof is preferably in the range of 5 to 95% by weight, and 20 to 85% by weight. The range of% is particularly preferable.

It is particularly preferable that the monofunctional (meth) acrylate derivative is a bromine-containing or chlorine-containing derivative.

The (meth) acrylate derivative having a bromine atom or a chlorine atom used in the present invention can be obtained by a known method. For example, it can be obtained by (meth) acrylic esterification of a bromine-substituted alcohol, a bromine-substituted phenol derivative, a chlorine-substituted alcohol, or a chlorine-substituted phenol derivative using (meth) acrylic acid or (meth) acrylic acid chloride.

Further, a bromine-substituted alcohol, a bromine-substituted phenol derivative, a chlorine-substituted alcohol or a chlorine-substituted phenol derivative is reacted with a reactive compound having an epoxy group or a cyclic ester compound, or a carboxylic acid compound having a hydroxyl group. It can also be obtained by converting a hydroxyl group into a (meth) acrylic ester.

Examples of the bromine-substituted alcohol and chlorine-substituted alcohol used here include dibromobutanol, dibromopropanol, bromobenzyl alcohol, dibromobenzyl alcohol, tribromobenzyl alcohol, dichlorobutanol, dichloropropanol, chlorobenzyl alcohol, dichlorobenzyl. Examples thereof include alcohol, trichlorobenzyl alcohol, dichlorobenzhydrol and the like.

Examples of the bromine-substituted phenol derivative and the chlorine-substituted phenol derivative include brimophenol, dibromophenol, tribromophenol, bromocresol, dibromocresol, tetrabromobisphenol A and chlorophenol. And dichlorophenol, trichlorophenol, chlorocresol, dichlorocresol, tetrachlorobisphenol A and the like.

Commercially available bromine-containing (meth) acrylate derivatives used in the present invention include, for example, 2,3-dibromopropyl acrylate manufactured by Tokyo Kasei Co., Ltd., "Daiichi Kogyo Seiyaku Co., Ltd." BR-30 "(tribromophenyl acrylate)," BR-31 "(ethylene oxide modified tribromophenyl acrylate)," BR-42 "(ethylene oxide modified tetrabromobisphenol A diacrylate)," BR-42M "(ethylene oxide modified tetra Bromobisphenol A dimethacrylate) and the like.

As the polymerizable compound which can be used in addition to the (meth) acrylate derivative having a bromine atom or a chlorine atom used in the present invention, for example, styrene, chlorostyrene, α-methylstyrene, divinylbenzene;
As a substituent, methyl, ethyl, propyl, butyl, amyl, 2-ethylhexyl, octyl, nonyl, dodecyl, hexadecyl, butoxyethyl, phenoxyethyl, allyl, methallyl, glycidyl, 2-hydroxyethyl, 2-hydroxypropyl, 3- Acrylate, methacrylate or fumarate having groups such as chloro-2-hydroxyethyl, dimethylaminoethyl, diethylaminoethyl; ethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol, 1,3-butylene glycol, tetramethylene glycol, hexamethylene Mono (meth) acrylates or poly (meth) acrylates such as glycol, neopentyl glycol, trimethylolpropane, glycerin and pentaerythritol. ) Acrylate; vinyl acetate, vinyl butyrate or vinyl benzoate, acrylonitrile, cetyl vinyl ether, limonene, cyclohexene, diallyl phthalate, 2-, 3- or 4-vinyl pyridine, acrylic acid, methacrylic acid, acrylamide, methacrylamide, N-hydroxy. Methylacrylamide or N-hydroxyethylmethacrylamide and their alkyl ether compounds; Di (meth) diol obtained by adding 2 moles or more of ethylene oxide or propylene oxide to 1 mole of neopentyl glycol.
Acrylate; Di- or tri (meth) acrylate of triol obtained by adding 3 mol or more of ethylene oxide or propylene oxide to 1 mol of trimethylolpropane; 2 mol or more of ethylene oxide or propylene oxide added to 1 mol of bisphenol A Di (meth) acrylate of the obtained diol; Reaction product of 1 mol of 2-hydroxyethyl (meth) acrylate and 1 mol of phenyl isocyanate or n-butyl isocyanate; Poly (meth) acrylate of dipentaerythritol; Pivalate ester neo Pentyl glycol diacrylate; Caprolactone modified hydroxypivalate neopentyl glycol diacrylate; Linear aliphatic diacrylate; Polyolefin modified neopentyl glycol - diacrylate - DOO; epoxy (meth) acrylate - DOO, polyester (meth) acrylate - DOO, polyurethane (meth) acrylate - DOO, polyether - can be mentioned ether (meth) acrylate.

Examples of the photopolymerization initiator include 2-hydroxy-2-methyl-1-phenylpropan-1-one (“Darocur 1173” manufactured by Merck), 1-hydroxycyclohexyl phenyl ketone (manufactured by Ciba Geigy). "Irgacure 184"), 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropane-1-
On (Merck "Darocur 1116"), benzyl dimethyl ketal (Ciba Geigy "Irgacure 651"), 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropanone-1 (Ciba)・ Geigy's "Irgacure 907"), 2,4-diethylthioxanthone (Nippon Kayaku's "Kayacure DET"
X ”) and ethyl p-dimethylaminobenzoate (“ Kayacure-EPA ”manufactured by Nippon Kayaku Co., Ltd.), isopropylthioxanthone (“ Cantacure ITX ”manufactured by Ward Prekinsop), and ethyl p-dimethylaminobenzoate. And the like.

The proportion of the photopolymerization initiator used is preferably in the range of 0.1 to 5.0% by weight based on the polymerizable composition.

The liquid crystal device of the present invention can also be manufactured from a liquid crystal material or a transparent polymer substance having a bromine atom or a chlorine atom by a solvent evaporation method or a melt cooling method.

[0052]

EXAMPLES The present invention will be described in more detail below by showing Examples of the present invention. However, the invention is not limited to these examples.

In the following examples, "%" represents "% by weight", and the meaning and contents of each symbol used for evaluation characteristics are shown in Table 1 below.

[0054]

[Table 1]

Further, the illuminance of ultraviolet rays was measured using a unimeter equipped with a light receiver "UVD-365PD" manufactured by Ushio Inc.

(Example 1) Liquid crystal composition "PN-001" manufactured by Rodick Co., Ltd. (see Table 2 below) 80.0%,
"KAYARAD-HX-620" (Nippon Kayaku Co., Ltd., caprolactone modified hydroxypivalate neopentyl glycol diacrylate) 11.76%, "B
R-31 "(manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., ethylene oxide-modified tribromophenyl acrylate) 7.84%, and" Darocur 1173 "(manufactured by Merck, as a polymerization initiator)
2-hydroxy-2-methyl-1-phenylpropane-
1-on) 0.4% of the light control layer forming material,
It is sandwiched between two ITO electrode glass substrates coated with 0μ glass fiber spacers,
While maintaining the temperature at 0 ° C., ultraviolet rays of 25 mW / cm ² were irradiated for 60 seconds to obtain a liquid crystal device having a light control layer with a thickness of 11.2 μ.

When the light control layer of the obtained liquid crystal device was observed with an electron microscope, a three-dimensional mesh-like transparent polymer substance was confirmed.

As a result of measuring the relationship between the applied voltage and the light transmittance of the obtained liquid crystal device, T ₀ = 4.8% and T ₁₀₀ = 9.
0.2%, CR = 18.79, V 10 = 4.0V rms, V 90
= 8.5V _rms , and the temperature characteristics were measured.
/ T = 10 mV _rms / ° C.

As described above, it is clear that the liquid crystal device of the present invention is a liquid crystal device which can be driven at a low voltage and has good temperature characteristics.

[0060]

[Table 2]

(Example 2) The liquid crystal composition "PN-00"
1 "80%," KAYARAD-HX-620 "9.8
%, "BR-30" (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., tribromophenyl acrylate) 9.8%, and "Darocur 11".
73 "0.4% of the light control layer forming material is 11.0μ
Two I coated with glass fiber spacers
Inserted into the TO electrode glass substrate, the entire substrate was 38.5
While maintaining the temperature at 0 ° C., ultraviolet rays of 25 mW / cm ² were irradiated for 60 seconds to obtain a liquid crystal device having a light control layer with a thickness of 11.6 μm.

When the light control layer of the obtained liquid crystal device was observed with an electron microscope, a transparent polymer substance having a three-dimensional network was confirmed.

When the relationship between the applied voltage and the light transmittance of this liquid crystal device was measured, T ₀ = 5.2% and T ₁₀₀ = 8.
9.5%, CR = 17.21, V 10 = 3.7V rms, V 90
= 8.0V _rms , temperature characteristics were measured
/ T = 15 mV _rms / ° C.

(Synthesis example) 2,3 in a 100 ml ampoule tube
4-trichlorophenol 30.5 g, ε-caprolactone 17.3 g, stannous octylate as catalyst 0.0
2 g was charged, the atmosphere was replaced with nitrogen, and the tube was sealed. This ampoule tube was put in an oil bath and reacted at 180 ° C. for 20 hours. After returning to room temperature, it was opened and the unreacted trichlorophenol was filtered off to obtain 24.8 g of a reaction product.

According to GPC (gel permeation chromatography) analysis, 2,3,3
It was confirmed that 4-trichlorophenol and ε-caprolactone monomers were not contained.

A stirrer, cooling tube, thermometer set 2
To a 00 ml four-necked flask, 6 g of this product, 4.2 g of triethylamine, 0.2 g of phenothiazine and 60 ml of cyclohexane were added, and 2.3 g of acryloyl chloride was gradually added dropwise while stirring so that the reaction temperature did not exceed 30 ° C. did. After completion of the dropping, the reaction was further continued for 3 hours, the precipitated salt was filtered off, the filtrate was washed with 100 ml of 0.1N hydrochloric acid aqueous solution, and then the solvent was distilled off under reduced pressure to obtain 7.8 g of a solid product.

The solid product was purified by column chromatography and recrystallized from ethanol to obtain 5.6 g of compound (1) (caprolactone-modified trichlorophenoxymonoacrylate).

Infrared spectroscopic measurement of the compound (1) showed that absorption of hydroxyl groups at 3400 to 3600 cm ^-1 was not observed, confirming that the compound (1) was completely acrylic esterified.

(Example 3) The liquid crystal composition "PN-00" was used.
1 "80%," KAYARAD-HX-620 "9.8
%, 9.8% of the compound (1) (caprolactone-modified trichlorophenoxymonoacrylate), and 0.4% of "Darocur 1173" as a light control layer forming material.
It is sandwiched between two ITO electrode glass substrates coated with 1.0 μm glass fiber spacers, and while maintaining the whole substrate at 41.2 ° C., 25 mW / cm ² of ultraviolet rays is applied to 60 μm.
Irradiation for 2 seconds gave a liquid crystal device having a light control layer with a thickness of 11.6 μm.

When the light control layer of the obtained liquid crystal device was observed with an electron microscope, a transparent polymer substance having a three-dimensional network was confirmed.

When the relationship between the applied voltage and the light transmittance of this liquid crystal device was measured, T ₀ = 5.5% and T ₁₀₀ = 8.
9.6%, CR = 16.29, V 10 = 4.2V rms, V 90
= 9.8V _rms , and the temperature characteristics were measured.
/ T = 45 mV _rms / ° C.

Comparative Example 1 The liquid crystal composition "PN-00"
1 "80.0%," KAYARAD-HX-620 "1
A dimming layer forming material composed of 9.6% and “Darocur 1173” 0.4% is sandwiched between two ITO electrode glass substrates coated with a 11.0 μm glass fiber spacer, and the entire substrate is 40 25mW / while maintaining at ℃
Irradiate 60 cm ² of ultraviolet rays for 60 seconds to adjust the thickness of the light control layer to 11.
A 4μ liquid crystal device was obtained.

When the light control layer of the obtained liquid crystal device was observed with an electron microscope, a transparent polymer substance having a three-dimensional network was confirmed.

When the relationship between the applied voltage and the light transmittance of this liquid crystal device was measured, T ₀ = 4.1% and T ₁₀₀ = 85.
2%, CR = 20.8, V 10 = 5.5V rms, V 90 = 1
It was 4.2V _rms , and when the temperature characteristic was measured,
T = 150 mV _rms / ° C.

Table 3 below shows the results obtained by comparing these values with each value in Examples 1 to 3 as 100.

[0076]

[Table 3]

As can be seen from Table 3 above, compared with the liquid crystal device of the present invention, the driving voltage is high and the temperature characteristics are poor,
It had a problem in practical use.

(Comparative Example 2) The liquid crystal composition "PN-00" was used.
1 "80.0%," KAYARAD-HX-620 "1
1.76%, "M-101" (manufactured by Toagosei Kagaku) 7.
The light control layer forming material consisting of 84% and "Darocur 1173" 0.4% is sandwiched between two ITO electrode glass substrates coated with 11.0μ glass fiber spacers, and the entire substrate is heated to 32 ° C. 25mW / cm while keeping
Irradiate ² ultraviolet rays for 60 seconds, and the thickness of the light control layer is 11.3
A liquid crystal device of μ was obtained.

When the light control layer of the obtained liquid crystal device was observed with an electron microscope, a three-dimensional mesh-like transparent polymer substance could be confirmed.

When the relationship between the applied voltage and the light transmittance of this liquid crystal device was measured, T ₀ = 5.6% and T ₁₀₀ = 90.
2%, CR = 16.1, V ₁₀ = 4.0 V _rms , V ₉₀ = 1
It is 0.4V _rms , and when the temperature characteristic is measured,
T = 130 mV _rms / ° C.

Table 4 below shows the results obtained by comparing these values with the values of Examples 1 to 3 as 100.

[0082]

[Table 4]

As can be seen from Table 4 above, the temperature characteristics were poorer than those of the liquid crystal device of the present invention, and there were practical problems.

The results of Examples 1 to 3 and Comparative Examples 1 and 2 described above are summarized in Table 5 below.

[0085]

[Table 5]

[0086]

The liquid crystal device of the present invention has a large area and is of a thin film type, and is different from the conventional liquid crystal dispersion type liquid crystal device or liquid crystal continuous layer type liquid crystal device in the above Tables 3 to 5.
As is clear from the figure, it is possible to drive at a low voltage of 10 V _rms or less, which makes it possible to use LCD LSIs and improve the temperature characteristics, so the change in drive voltage at each operating temperature is small. Therefore, the practicality is improved.

Therefore, not only this type of dimming liquid crystal device of the related art, but also a large area and a thin, more advanced character,
Extremely useful as a liquid crystal device for displaying graphics

Claims (6)

[Claims] 1. A substrate having at least one transparent electrode layer, and a light control layer supported between these substrates, wherein the light control layer comprises a liquid crystal material and a transparent polymer substance. A liquid crystal device containing the liquid crystal device, wherein the transparent polymer substance is obtained by polymerizing a polymerizable composition containing a polymerizable compound having a bromine atom or a chlorine atom. 2. The liquid crystal device according to claim 1, wherein the polymerizable composition contains a (meth) acrylate derivative having a bromine atom or a chlorine atom. 3. The liquid crystal device according to claim 1, wherein the light control layer is formed by forming a three-dimensional network structure of a transparent polymer material in a continuous layer of liquid crystal. 4. A photopolymerizable composition containing (1) a liquid crystal material and (2) a (meth) acrylate derivative having a bromine atom or a chlorine atom between at least one transparent substrate having an electrode layer. And (3) a light control layer forming material containing a photopolymerization initiator is sandwiched, and the light control layer forming material is irradiated with an actinic ray to polymerize the polymerizable composition, whereby a liquid crystal material and a transparency are obtained. A method for manufacturing a liquid crystal device, which comprises forming a light control layer containing a polymer substance. 5. The method for producing a liquid crystal device according to claim 4, wherein the light control layer has a three-dimensional mesh-like transparent solid substance in a continuous layer of the liquid crystal material. 6. The light control layer forming material initiates polymerization in a uniform liquid state.
A method for manufacturing a liquid crystal device according to.