JPH0756153A - Liquid crystal optical element and its production - Google Patents

Abstract

PURPOSE:To embody a liquid crystal optical element whose electric charge holding characteristic is excellent. CONSTITUTION:A pair of upper and lower substrates 11 and 12 where electrodes 13 are provided is stuck through resin 14 functioning both as a spacer and a seal, and a compound obtained by mixing an adsorption material 16 in a composition consisting of liquid crystal and a polymerizing material is inserted and held between the substrates 11 and 12. After an electric field is impressed on the compound through the electrodes 13, the polymerization of the polymerizing material is finished and the liquid crystal optical element using the high polymer distribution type liquid crystal 15 is completed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal optical element using a polymer-dispersed liquid crystal in which a liquid crystal is dispersed and held in a polymer resin matrix, and a method for producing the same.

[0002]

2. Description of the Related Art In recent years, a polymer-dispersed liquid crystal in which a nematic liquid crystal is dispersed and held in a polymer having the same refractive index as that of liquid crystal molecules is sandwiched between a pair of upper and lower substrates having electrodes to determine the presence or absence of an electric field. The liquid crystal optical element that changes the refractive index of the liquid crystal to switch between the scattering state and the transmitting state has attracted much research and developer attention.
631, Japanese Patent Laid-Open No. 60-252687, and Japanese Patent Laid-Open No. 61-502128).

FIG. 7 is a schematic view showing the display principle of this liquid crystal optical element.

In the state where no voltage is applied ((a) in the figure), since the molecular axes of the liquid crystal 74 are oriented in random directions, the refractive index of the liquid crystal region is different from that of the surrounding polymer phase 75, and the liquid crystal optical element has a different refractive index. The incident light 72 that has entered becomes scattered light 73, and as a result, a scattered state is obtained. On the other hand, when an electric field is applied to the electrode 71 ((b) in the figure), the molecular axes of the liquid crystal 74 are aligned in the direction of the electric field, and for light incident perpendicularly on the substrate, the refractive index of the liquid crystal region is around. Since the refractive index of the polymer phase 75 is almost the same as that of the polymer phase 75, light is not scattered and the transmitted light 76 is obtained.
A transparent state is obtained.

Since the liquid crystal optical element using the polymer-dispersed liquid crystal utilizes light scattering, it is not necessary to use a polarizing plate, and unlike a conventional twisted nematic (TN) type liquid crystal optical element, Compared to liquid crystal optical elements that require the use of polarizing plates to obtain linearly polarized light,
A wide viewing angle display is possible. Further, the conventional TN type liquid crystal optical element or the like needs to accurately control the alignment treatment and the upper and lower substrate intervals, and thus has a problem that display unevenness is likely to occur when displaying a large area. The liquid crystal optical element using the molecular dispersion type liquid crystal is characterized in that alignment treatment is not necessary, the substrate spacing is not strictly controlled, and a large area liquid crystal optical element can be easily manufactured.

[0006]

By the way, in order to obtain a high scattering state in a liquid crystal optical element using a polymer dispersed liquid crystal, the difference between the refractive index of the liquid crystal phase and the refractive index of the polymer phase is increased. Therefore, a cyano-based liquid crystal material having a high refractive index is often used as the liquid crystal material. However, the cyano-based liquid crystal material has a high polarity and a large dielectric anisotropy (Δε), and thus has a drawback that impurities are easily taken in. Therefore, when a polymer-dispersed liquid crystal is produced, when mixed with a polymerizable material or the like, impurities such as an ionic substance contained therein are dissolved into the liquid crystal, and as a result, the specific resistance of the liquid crystal is lowered. Since the specific resistance of the liquid crystal is lowered in this way, a liquid crystal optical element using a polymer-dispersed liquid crystal that uses a cyano-based liquid crystal generally has poor charge retention characteristics, which causes display failure during active matrix driving. Had the problem of causing.

In view of such problems of the conventional polymer-dispersed liquid crystal, the present invention suppresses the decrease in the specific resistance of the liquid crystal and prevents the deterioration of the charge retention characteristics. And a liquid crystal optical element having good display performance.

[0008]

As described above, it is considered that the dissolution of impurities such as ionic substances into the liquid crystal is related to the decrease in the specific resistance of the liquid crystal. Therefore, in order to suppress the decrease in the specific resistance of the liquid crystal, it is necessary to reduce impurities such as ionic substances present in the polymer dispersed liquid crystal. In the liquid crystal optical element according to any one of claims 1 to 4 of the present invention, a polymer-dispersed liquid crystal sandwiched between a pair of upper and lower substrates having transparent electrodes provided on at least one substrate is mixed with an adsorbent. A liquid crystal optical element characterized by being a molecular dispersion type liquid crystal, and the method for producing a liquid crystal optical element according to claim 5 and 6 of the present invention is to use an adsorbent in a composition comprising liquid crystal and a polymerizable material. A liquid crystal optical element, characterized in that the mixed mixture is sandwiched between a pair of upper and lower substrates provided with electrodes, an electric field is applied to the mixture, polymerization of a polymerizable material is completed, and a liquid crystal optical element is manufactured. The method of manufacturing a liquid crystal optical element according to claim 11 of the present invention comprises sandwiching a mixture of a composition comprising liquid crystal and a polymerizable material with an adsorbent between a pair of upper and lower substrates provided with electrodes. , The polymerizable material is polymerized, and After forming the dispersion type liquid crystal, an electric field is applied to the polymer-dispersed liquid crystal, a manufacturing method of the liquid crystal optical element, characterized in that to complete the liquid crystal optical element. Further, in the liquid crystal optical element according to claims 16 to 19 of the present invention, the substrate having electrodes holding the polymer-dispersed liquid crystal in between is a substrate having a coating film prepared by mixing an adsorbent on the electrodes. A method for producing a liquid crystal optical element according to claims 20 and 21 of the present invention is a liquid crystal optical element characterized in that a coating film is prepared by mixing an adsorbent with a composition comprising liquid crystal and a polymerizable material. A method for producing a liquid crystal optical element, which comprises sandwiching the substrate with electrodes, applying an electric field to the composition, and then completing the polymerization of a polymerizable material to produce a liquid crystal optical element. The method for producing a liquid crystal optical element according to claim 26 of the present invention is characterized in that a composition comprising a liquid crystal and a polymerizable material is sandwiched between substrates with an electrode provided with a coating film in which an adsorbent is mixed to polymerize the polymerizable material. An electric field is applied to the completed, polymer-dispersed liquid crystal to form a liquid crystal. A method for producing a liquid crystal optical element, characterized in that to complete the academic element.

[0009]

By applying an electric field to a mixture obtained by mixing a composition composed of liquid crystal and a polymerizable material with an adsorbent, impurities such as ionic substances contained in the polymerizable material are adsorbed by the adsorbent. As a result, by successively completing the polymerization of the polymerizable material, the concentration of impurities in the liquid crystal of the polymer-dispersed liquid crystal is reduced, the decrease in the specific resistance of the liquid crystal is suppressed, and the deterioration of the charge retention property does not occur. Therefore, a liquid crystal optical element with excellent display performance can be realized. Also, complete the polymerization of the polymerizable material,
Even when an electric field is applied to the formed polymer-dispersed liquid crystal, a liquid crystal optical element having excellent charge retention characteristics and excellent display performance can be realized. Further, instead of mixing the adsorbent in the polymer-dispersed liquid crystal, a coating film in which the adsorbent is mixed is provided on the surface of the substrate on which the electrodes sandwiching the polymer-dispersed liquid crystal are provided to prevent the polymerization of the polymerizable material. Similar effects can be achieved by applying an electric field after the polymerization. That is, when an electric field is applied to a composition composed of liquid crystal and a polymerizable material, impurities such as ionic substances contained in the polymerizable material are adsorbed on the coating film mixed with the adsorbents provided on the surfaces of the upper and lower substrates. As a result, impurities such as ionic substances existing in the polymer-dispersed liquid crystal are reduced, the specific resistance of the liquid crystal is not lowered and the charge retention property is not deteriorated, and a liquid crystal optical element having excellent display performance can be realized.
The adsorbent is preferably an inorganic material, and silica-based, alumina-based, metal oxides such as zeolite, activated carbon, and porous glass can be used. The admixture amount of these adsorbents is not particularly limited, but as a rough guide, when mixed in the polymer-dispersed liquid crystal, 0.01 to 5% by weight is appropriate with respect to the polymer-dispersed liquid crystal, When mixed in the coating film, 0.01 to 5% by weight is suitable for the coating material. When the mixing amount is less than 0.01% by weight,
The adsorbability of impurities decreases, the charge retention characteristics of the liquid crystal optical element deteriorate, and when the mixing amount is more than 5% by weight, the transmittance of the liquid crystal optical element is adversely affected. The size of the adsorbent is
Although not particularly limited, those having a size of several nm to several μm which are generally used as an adsorbent are desirable.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The liquid crystal optical elements according to the first to fifteenth aspects of the present invention and the manufacturing method thereof will be described below with reference to the drawings.

FIG. 1 is a diagram showing an outline of a liquid crystal optical element produced by using the polymer-dispersed liquid crystal according to the first to fourth aspects of the present invention. A pair of upper and lower substrates 11 and 12 provided with electrodes 13 are bonded via a spacer / sealing resin 14 to complete an empty cell. A liquid crystal optical element was completed by sandwiching a polymer-dispersed liquid crystal 15 in which an adsorbent 16 such as a metal oxide was mixed in the completed empty cell.

FIG. 2 shows the fifth to tenth aspects of the present invention.
It is a figure which shows the outline of the manufacturing method of the liquid crystal optical element using the polymer dispersion type liquid crystal described. A pair of upper and lower substrates 21 and 22 provided with electrodes 23 are bonded together via a spacer / sealing resin 24 to form an empty cell. The empty cell is made of a liquid crystal and an uncured photopolymerizable or thermopolymerizable polymerizable material. Composition 2
A mixture in which the adsorbent 26 such as a metal oxide is mixed is injected into 5. After the injection is completed, an electric field 27 is applied to the mixture through the electrode 23 for a certain time. After that, after the electric field is removed or the electric field is applied, the polymerization of the polymerizable material is completed to complete a liquid crystal optical element made of a polymer-dispersed liquid crystal.

FIG. 3 shows claims 11 to 1 of the present invention.
FIG. 6 is a diagram showing an outline of a method for producing a liquid crystal optical element using the polymer-dispersed liquid crystal described in 5. A pair of upper and lower substrates 31 and 32 provided with electrodes 33 are prepared, and an empty cell completed by bonding via a spacer / sealing resin 34 is filled with liquid crystal and uncured photopolymerizable or thermopolymerizable through an opening. A mixture in which an adsorbent 36 such as a metal oxide is mixed with a composition of materials is injected. After the injection is completed, the polymerization of the polymerizable material is completed to form the polymer-dispersed liquid crystal 35, and then the electric field 37 is applied to the polymer-dispersed liquid crystal through the electrode 33 for a certain period of time to form a polymer-dispersed liquid crystal optical. The element is completed. Hereinafter, specific examples will be described in more detail.

(Example 1) Two glass substrates having transparent electrodes (ITO electrodes) made of indium / tin oxide are left open, and glass having a diameter of 13 μm is used as a spacer so that the ITO electrode surfaces face each other. The fibers were pasted together with an ultraviolet curable resin, and an ultrahigh pressure mercury lamp was used as a light source to cure and adhere the resin with ultraviolet rays to complete an empty cell.

Next, 8.200 g of E8 (manufactured by Merck Japan Ltd.) as a liquid crystal material and 0.600 g of 2 ethylhexyl acrylate as a polymer-forming monomer were added.
Hydroxyethyl acrylate 0.600 g, Biscoat 823 as an oligomer (Osaka Organic Chemical Industry Co., Ltd.)
(Prepared) and 0.660 g of benzyl dimethyl ketal (manufactured by Nippon Kayaku Co., Ltd.) as a photopolymerization initiator were prepared, and the composition comprising the above materials was heated to 50 ° C. to make them compatible with each other. Then, 0.020 g of aluminum oxide having a particle diameter of 0.2 μm was mixed. Then, the mixture is heated to 50 ° C.
After sufficiently stirring at 50 ° C., it was injected into the empty cell prepared by the above-described manufacturing method at 50 ° C. through the opening. After the injection was completed, the opening was sealed and irradiated with ultraviolet rays (intensity: 57 mW / cm ² ) for 10 seconds at 50 ° C. using a super-high pressure mercury lamp as a light source to complete a liquid crystal cell composed of polymer dispersed liquid crystal. The charge retention characteristics of the liquid crystal cell thus completed were evaluated. The charge retention characteristics are: frame cycle 30 Hz, voltage ± 5 V,
The voltage holding characteristics when a rectangular wave having an ON time of 60 μs was applied to the liquid crystal cell was evaluated as an index. The voltage holding characteristic was quantified as a voltage holding ratio R. The voltage holding ratio was defined as the value obtained by measuring the potential between the electrodes and dividing the integrated value by the integrated value of 100% holding. The voltage holding ratio of 100% means that the voltage accumulated within the ON time does not change at all during the frame period thereafter. FIG. 8 shows a measurement waveform of the voltage holding ratio and a measurement example. In FIG. 8B, the voltage holding ratio R is represented by (Equation 1).

[0016]

[Equation 1]

The voltage holding ratio of the liquid crystal cell manufactured this time is 4
It was 60.5% at 0 ° C.

(Example 2) Two glass substrates having transparent electrodes (ITO electrodes) made of indium / tin oxide are left open, and glass having a diameter of 13 μm is used as a spacer so that the ITO electrode surfaces face each other. The fibers were pasted together with an ultraviolet curable resin, and an ultrahigh pressure mercury lamp was used as a light source to cure and adhere the resin with ultraviolet rays to complete an empty cell.

Next, 8.200 g of E8 (manufactured by Merck Japan Ltd.) as a liquid crystal material and 0.600 g of 2 ethylhexyl acrylate as a polymer-forming monomer were added.
Hydroxyethyl acrylate 0.600 g, Biscoat 823 as an oligomer (Osaka Organic Chemical Industry Co., Ltd.)
(Prepared) and 0.660 g of benzyl dimethyl ketal (manufactured by Nippon Kayaku Co., Ltd.) as a photopolymerization initiator were prepared, and the composition comprising the above materials was heated to 50 ° C. to make them compatible with each other. , Titanium oxide with a particle size of 0.2 μm to 0.0
20 g were mixed. Then, after thoroughly stirring the mixture at 50 ° C., 50 ° C. was added to the empty cell prepared by the above manufacturing method.
Then, it was injected from the opening. After the injection was completed, an AC electric field of 5 V and 30 Hz was applied to the mixture through the ITO electrode at 50 ° C. for 30 minutes. Immediately after the opening was sealed and the electric field was removed, ultraviolet rays (intensity: 57 mW / cm ² ) were irradiated for 10 seconds at 50 ° C. using an ultra-high pressure mercury lamp as a light source to form a liquid crystal cell composed of polymer-dispersed liquid crystal. completed. The voltage holding ratio of the liquid crystal cell thus completed was 65.5% at 40 ° C.

(Embodiment 3) A glass having a diameter of 13 μm is used as a spacer so that two ITO glass substrates having transparent electrodes (ITO electrodes) made of indium / tin oxide are left open and the ITO electrode surfaces face each other. The fibers were pasted together with an ultraviolet curable resin, and an ultrahigh pressure mercury lamp was used as a light source to cure and adhere the resin with ultraviolet rays to complete an empty cell.

Next, 8.200 g of E8 (manufactured by Merck Japan Ltd.) as a liquid crystal material and 0.600 g of 2 ethylhexyl acrylate as a polymer-forming monomer were added.
Hydroxyethyl acrylate 0.600 g, Biscoat 823 as an oligomer (Osaka Organic Chemical Industry Co., Ltd.)
(Prepared) and 0.660 g of benzyl dimethyl ketal (manufactured by Nippon Kayaku Co., Ltd.) as a photopolymerization initiator were prepared, and the composition comprising the above materials was heated to 50 ° C. to make them compatible with each other. , Titanium oxide with a particle size of 0.2 μm to 0.0
20 g were mixed. Then, after thoroughly stirring the mixture at 50 ° C., 50 ° C. was added to the empty cell prepared by the above manufacturing method.
Then, it was injected from the opening. After the injection was completed, an AC electric field of 5 V and 30 Hz was applied to the mixture through the ITO electrode at 50 ° C. for 30 minutes. The opening is sealed and the electric field (5
(V, 30 Hz) was applied and ultraviolet rays (intensity: 57 mW / cm ² ) were irradiated for 10 seconds using a super-high pressure mercury lamp as a light source to complete a liquid crystal cell composed of polymer dispersed liquid crystal. The voltage holding ratio of the liquid crystal cell thus completed is 6 at 40 ° C.
It was 5.2%.

(Embodiment 4) A glass having a diameter of 13 μm was used as a spacer so that two ITO glass substrates having transparent electrodes (ITO electrodes) formed of indium tin oxide were left open and the ITO electrode surfaces face each other. The fibers were pasted together with an ultraviolet curable resin, and an ultrahigh pressure mercury lamp was used as a light source to cure and adhere the resin with ultraviolet rays to complete an empty cell.

Next, 8.200 g of E8 (manufactured by Merck Japan Ltd.) as a liquid crystal material and 0.600 g of 2 ethylhexyl acrylate as a polymer-forming monomer were used.
Hydroxyethyl acrylate 0.600 g, Biscoat 823 as an oligomer (Osaka Organic Chemical Industry Co., Ltd.)
(Prepared) and 0.660 g of benzyl dimethyl ketal (manufactured by Nippon Kayaku Co., Ltd.) as a photopolymerization initiator were prepared, and the composition comprising the above materials was heated to 50 ° C. to make them compatible with each other. , 0.010 g of aluminum oxide having a particle diameter of 0.2 μm and silicon dioxide of 0.2 μm having a particle diameter of 0.2 μm.
010 g and 0.010 g of calcium oxide having a particle diameter of 0.2 μm were mixed. After sufficiently stirring the mixture at 50 ° C., the mixture was added to the empty cell prepared by the above-described manufacturing method at 50 ° C.,
It was injected through the opening. After the injection is completed, the opening is sealed and 5
Ultraviolet light (intensity: 57
mW / cm ² ) was irradiated for 10 seconds to complete a liquid crystal cell made of polymer dispersed liquid crystal. The voltage holding ratio of the liquid crystal cell thus completed was 62.8% at 40 ° C.

(Embodiment 5) A glass having a diameter of 13 μm is used as a spacer so that two ITO glass substrates having transparent electrodes (ITO electrodes) formed of indium tin oxide are left open and the ITO electrode surfaces face each other. The fibers were pasted together with an ultraviolet curable resin, and an ultrahigh pressure mercury lamp was used as a light source to cure and adhere the resin with ultraviolet rays to complete an empty cell.

Next, 8.200 g of E8 (manufactured by Merck Japan Co., Ltd.) as a liquid crystal material and 0.600 g of 2 ethylhexyl acrylate as a polymer-forming monomer were added.
Hydroxyethyl acrylate 0.600 g, Biscoat 823 as an oligomer (Osaka Organic Chemical Industry Co., Ltd.)
0.600 g, and benzyl dimethyl ketal (manufactured by Nippon Kayaku Co., Ltd.) 0.060 g as a photopolymerization initiator, and aluminum silicate having a particle diameter of 0.2 μm is added to the composition composed of the above materials. 0.020 g was mixed. After sufficiently stirring the mixture at 50 ° C., the mixture was injected into the empty cell prepared by the above-described manufacturing method at 50 ° C. through the opening. After the injection was completed, the opening was sealed and irradiated with ultraviolet rays (intensity: 57 mW / cm ² ) at 50 ° C. for 10 seconds using an ultra-high pressure mercury lamp as a light source to form a polymer dispersed liquid crystal, and then at 80 ° C. An AC electric field of 5 V and 30 Hz was applied to the polymer dispersed liquid crystal through an ITO electrode for 30 minutes to complete a liquid crystal cell. The voltage holding ratio of the completed liquid crystal cell is 61.5 at 40 ° C.
%Met.

Next, an experimental example for comparison will be shown.

(Comparative Example 1) A glass having a diameter of 13 μm was used as a spacer so that the ITO electrode surfaces face each other with two glass substrates having transparent electrodes (ITO electrodes) made of indium tin oxide formed thereon. The fibers were pasted together with an ultraviolet curable resin, and an ultrahigh pressure mercury lamp was used as a light source to cure and adhere the resin with ultraviolet rays to complete an empty cell.

Next, 8.200 g of E8 (manufactured by Merck Japan Co., Ltd.) as a liquid crystal material and 0.600 g of 2 ethylhexyl acrylate as a polymer forming monomer were added.
Hydroxyethyl acrylate 0.600 g, Biscoat 823 as an oligomer (Osaka Organic Chemical Industry Co., Ltd.)
Prepared) and 0.060 g of benzyl dimethyl ketal (manufactured by Nippon Kayaku Co., Ltd.) as a photopolymerization initiator were prepared, and the composition comprising the above materials was sufficiently stirred at 50 ° C. In an empty cell made by the manufacturing method at 50 ° C,
It was injected through the opening. After the injection is completed, the opening is sealed and 5
Ultraviolet light (intensity: 57
mW / cm ² ) was irradiated for 10 seconds to complete a liquid crystal cell made of polymer dispersed liquid crystal. The voltage holding ratio of the liquid crystal cell thus completed was 38.1% at 40 ° C., which was considerably lower than that of the liquid crystal cell using the polymer dispersed liquid crystal containing the adsorbent (Example 1).

Although the temperature at which the electric field treatment is carried out is not limited, when the electric field treatment is carried out before the polymerization of the polymerizable material as in the embodiment of the present invention, a composition comprising a liquid crystal and the polymerizable material is used. At a temperature at which the polymer-dispersed liquid crystal formed by completing the polymerization of the polymerizable material is subjected to an electric field treatment at a temperature at which the liquid crystal used for the polymer-dispersed liquid crystal exhibits isotropicity. The voltage holding ratio of the liquid crystal cell is higher when the electric field treatment is performed. At low temperatures, the migration of impurities is poor and the adsorption to adsorbents and coatings is poor, and as a result, the voltage holding ratio does not increase so much.
The strength and frequency of the electric field to be subjected to the electric field treatment and the application time are not limited to those shown in the above embodiment, and can be appropriately changed and used. Further, a DC electric field may be applied in a range where materials such as liquid crystal and a polymerizable material are not deteriorated as well as AC.

The liquid crystal material used for the polymer dispersed liquid crystal is
It is not limited to E8 described in the above embodiment,
Other cyano liquid crystals, various nematic liquid crystals such as fluorine liquid crystals, and cholesteric liquid crystals may be used. In this example, the polymer dispersed liquid crystal is described by using the polymer dispersed liquid crystal in which the liquid crystal phase is separated into droplets, but the invention is not limited to this. The same effect can be achieved with a polymer-dispersed liquid crystal in which the liquid crystal forms a continuous phase. Further, in this example, the ratio of the liquid crystal in the polymer dispersed liquid crystal is set to about 82% by weight, but it is not limited to this. As the polymer-forming monomer, 2 ethylhexyl acrylate or 2 hydroxyethyl acrylate was used this time, but it is not limited thereto. Neopentyl glycol acrylate, hexanediol diacrylate, diethylene glycol diacrylate, tripropylene glycol diacrylate. , Commercially available acrylic monomers such as polyethylene glycol diacrylate and trimethylolpropane triacrylate, and widely applicable commercial products other than acrylic monomers. The oligomer is not limited to Viscoat 823 (manufactured by Osaka Organic Chemical Industry Co., Ltd.) shown in the examples.

Also, the polymerization initiator is not limited to benzyl dimethyl ketal (manufactured by Nippon Kayaku Co., Ltd.), and Darocur 1173 manufactured by Merck Co., Ltd., Irgacure 184, Irgacure 651 manufactured by Ciba-Gaiki, etc. But it's okay.

Further, the polymer material used is not limited to the photo-curable resin shown in the above embodiment, but may be a thermosetting resin or a thermoplastic resin.

Next, claim 16 to claim 30 of the present invention.
The described liquid crystal optical element and its manufacturing method will be described with reference to the drawings. FIG. 4 is a diagram schematically showing a liquid crystal optical element produced by using the polymer dispersed liquid crystal according to claims 16 to 19 of the present invention. A pair of upper and lower substrates 41 and 42 provided with a coating film 47 containing an adsorbent 46 such as a metal oxide on the electrode 43 are bonded via a spacer / sealing resin 44 to complete an empty cell. A polymer dispersed liquid crystal 45 was sandwiched between the completed empty cells to complete a liquid crystal optical element.

FIG. 5 shows claims 20 to 2 of the present invention.
FIG. 6 is a diagram showing an outline of a method for producing a liquid crystal optical element using the polymer-dispersed liquid crystal described in 5. A pair of upper and lower substrates 51, 52 having a coating film 58 containing an adsorbent 56 such as a metal oxide on the electrode 53 are bonded via a spacer / sealing resin 54 to an empty cell, and liquid crystal and uncured from the opening. The composition 55 made of the photopolymerizable or heat-polymerizable polymerizable material is injected. After the injection is completed, an electric field 57 is applied to the composition 55 through the electrode 53 for a certain period of time. After that, after the electric field is removed or the electric field is applied, the polymerization of the polymerizable material is completed to complete a liquid crystal optical element made of a polymer-dispersed liquid crystal.

FIG. 6 shows claims 26 to 3 of the present invention.
FIG. 3 is a diagram showing an outline of a method for producing a liquid crystal optical element using the polymer-dispersed liquid crystal described in 0. A pair of upper and lower substrates 61, 62 having a coating film 68 containing an adsorbent 66 such as a metal oxide on the electrode 63 are bonded via a spacer / sealing resin 64 to an empty cell, and liquid crystal and uncured from the opening. The composition comprising the photopolymerizable or heat-polymerizable polymerizable material is injected.
After the injection is completed, the polymerization of the polymerizable material is completed, and the space between the substrates 6
An electric field 67 was applied to the polymer dispersed liquid crystal 65 formed in Nos. 1 and 62 through the electrode 63 for a certain period of time to complete a liquid crystal optical element made of the polymer dispersed liquid crystal.

Hereinafter, the present invention will be described in more detail with reference to specific examples.

Example 6 A 3.0% by weight solution of a polyimide varnish (manufactured by Nissan Kagaku Co., Ltd .: trade name SE-4110) was prepared. A solution was prepared by mixing 100 g of the polyimide solution with 0.5 g of aluminum oxide having a particle size of 0.2 μm. Subsequently, two glass substrates having transparent electrodes (ITO electrodes) made of indium / tin oxide were prepared, and a polyimide solution prepared by mixing the above-described aluminum oxide on the ITO electrodes of each glass substrate was set to 2300 rpm. ,
After spin coating under the condition of 60 seconds, it was baked at 260 ° C. for 1 hour to form a polyimide coating film mixed with aluminum oxide. The film thickness of this polyimide coating film was about 80 nm.

The two glass substrates thus treated were bonded together with a UV curable resin in which glass fibers having a diameter of 13 μm were dispersed as spacers so that the polyimide coating surfaces face each other, leaving the openings, and the superposed light source. Using a high pressure mercury lamp, the resin was cured and adhered by ultraviolet rays to complete an empty cell. Next, 8.200 g of E8 (manufactured by Merck Japan Ltd.) as a liquid crystal material, 0.600 g of 2 ethylhexyl acrylate and 0.600 g of 2 hydroxyethyl acrylate as a polymer-forming monomer, and Biscoat 828 (Osaka Organic Chemical Industry) as an oligomer. (Made by Co., Ltd.)
Was prepared and 0.060 g of benzyl dimethyl ketal (manufactured by Nippon Kayaku Co., Ltd.) as a photopolymerization initiator was prepared, and the composition comprising the above materials was sufficiently stirred at 50 ° C. It injected at 50 degreeC into the produced empty cell from the opening part. After the injection is completed, the opening is sealed and the temperature is 50 ° C.
Ultraviolet light (intensity: 57mW
/ Cm ² ) for 10 seconds to complete a liquid crystal cell made of polymer dispersed liquid crystal. The voltage holding ratio of the liquid crystal cell thus completed was 62.1% at 40 ° C.

Example 7 A 3.0% by weight solution of a polyimide varnish (manufactured by Nissan Kagaku Co., Ltd .: trade name SE-4110) was prepared. A solution was prepared by mixing 100 g of the polyimide solution with 0.5 g of aluminum oxide having a particle size of 0.2 μm. Subsequently, two glass substrates having transparent electrodes (ITO electrodes) made of indium / tin oxide were prepared, and a polyimide solution prepared by mixing the above-described aluminum oxide on the ITO electrodes of each glass substrate was set to 2300 rpm. ,
After spin coating under the condition of 60 seconds, it was baked at 260 ° C. for 1 hour to form a polyimide coating film mixed with aluminum oxide. The film thickness of this polyimide coating film was about 80 nm.

The two glass substrates thus treated were bonded together with a UV curable resin in which glass fibers having a diameter of 13 μm were dispersed as spacers so that the polyimide coating surfaces face each other, leaving the openings, and the superposed light source. Using a high pressure mercury lamp, the resin was cured and adhered by ultraviolet rays to complete an empty cell. Next, 8.200 g of E8 (manufactured by Merck Japan Ltd.) as a liquid crystal material, 0.600 g of 2 ethylhexyl acrylate and 0.600 g of 2 hydroxyethyl acrylate as a polymer-forming monomer, and Biscoat 828 (Osaka Organic Chemical Industry) as an oligomer. (Made by Co., Ltd.)
Was prepared, and 0.060 g of benzyl dimethyl ketal (manufactured by Nippon Kayaku Co., Ltd.) as a photopolymerization initiator was prepared, and the composition comprising the materials was sufficiently stirred at 50 ° C. to make them compatible with each other. 50 in the empty cell manufactured by the above-mentioned manufacturing method.
Poured through the opening at ° C. After the injection was completed, an AC electric field of 5 V and 30 Hz was applied to the composition through an ITO electrode at 50 ° C. for 30 minutes. Immediately after the opening was sealed and the electric field was removed, ultraviolet rays (intensity: 57 mW / cm ² ) were irradiated for 10 seconds at 50 ° C. using an ultra-high pressure mercury lamp as a light source to form a liquid crystal cell composed of polymer-dispersed liquid crystal. completed. The voltage holding ratio of the liquid crystal cell thus completed was 64.0% at 40 ° C.

Example 8 A 3.0% by weight solution of a polyimide varnish (manufactured by Nissan Kagaku Co., Ltd .: trade name SE-4110) was prepared. A solution was prepared by mixing 100 g of the polyimide solution with 0.5 g of aluminum oxide having a particle size of 0.2 μm. Subsequently, two glass substrates having transparent electrodes (ITO electrodes) made of indium / tin oxide were prepared, and a polyimide solution prepared by mixing the above-described aluminum oxide on the ITO electrodes of each glass substrate was set to 2300 rpm. ,
After spin coating under the condition of 60 seconds, it was baked at 260 ° C. for 1 hour to form a polyimide coating film mixed with aluminum oxide. The film thickness of this polyimide coating film was about 80 nm.

The two glass substrates thus treated were bonded together with a UV curable resin in which glass fibers having a diameter of 13 μm were dispersed as spacers so that the polyimide coating surfaces face each other, leaving the openings, and the superposed light source. Using a high pressure mercury lamp, the resin was cured and adhered by ultraviolet rays to complete an empty cell. Next, 8.200 g of E8 (manufactured by Merck Japan Ltd.) as a liquid crystal material, 0.600 g of 2 ethylhexyl acrylate and 0.600 g of 2 hydroxyethyl acrylate as a polymer-forming monomer, and Biscoat 828 (Osaka Organic Chemical Industry) as an oligomer. (Made by Co., Ltd.)
Was prepared, and 0.060 g of benzyl dimethyl ketal (manufactured by Nippon Kayaku Co., Ltd.) as a photopolymerization initiator was prepared, and the composition comprising the materials was sufficiently stirred at 50 ° C. to make them compatible with each other. 50 in the empty cell manufactured by the above-mentioned manufacturing method.
Poured through the opening at ° C. After the injection was completed, an AC electric field of 5 V and 30 Hz was applied to the composition through an ITO electrode at 50 ° C. for 30 minutes. The opening is sealed and the electric field (5 V, 3
While applying 0 Hz), ultraviolet rays (intensity: 57 mW / cm ² ) were irradiated at 50 ° C. for 10 seconds using an ultra-high pressure mercury lamp as a light source to complete a liquid crystal cell composed of a polymer-dispersed liquid crystal.
The voltage holding ratio of the completed liquid crystal cell is 6 at 40 ° C.
It was 4.7%.

Example 9 A 3.0% by weight solution of polyimide varnish (manufactured by Nissan Kagaku Co., Ltd .: trade name SE-4110) was prepared. A solution was prepared by mixing 100 g of the polyimide solution with 0.5 g of aluminum oxide having a particle size of 0.2 μm. Subsequently, two glass substrates having transparent electrodes (ITO electrodes) made of indium / tin oxide were prepared, and a polyimide solution prepared by mixing the above-described aluminum oxide on the ITO electrodes of each glass substrate was set to 2300 rpm. ,
After spin coating under the condition of 60 seconds, it was baked at 260 ° C. for 1 hour to form a polyimide coating film mixed with aluminum oxide. The film thickness of this polyimide coating film was about 80 nm.

The two glass substrates thus treated were bonded together with a UV curable resin in which glass fibers having a diameter of 13 μm were dispersed as spacers so that the polyimide coating surfaces face each other, leaving the openings, and the superposed light source. Using a high pressure mercury lamp, the resin was cured and adhered by ultraviolet rays to complete an empty cell. Next, 8.200 g of E8 (manufactured by Merck Japan Ltd.) as a liquid crystal material, 0.600 g of 2 ethylhexyl acrylate and 0.600 g of 2 hydroxyethyl acrylate as a polymer-forming monomer, and Biscoat 828 (Osaka Organic Chemical Industry) as an oligomer. (Made by Co., Ltd.)
Was prepared, and 0.060 g of benzyl dimethyl ketal (manufactured by Nippon Kayaku Co., Ltd.) as a photopolymerization initiator was prepared, and the composition comprising the materials was sufficiently stirred at 50 ° C. to make them compatible with each other. 50 in the empty cell manufactured by the above-mentioned manufacturing method.
Poured through the opening at ° C. After the injection is completed, the opening is sealed and the ultra-high pressure mercury lamp is used as a light source to emit ultraviolet rays (strength: 57 m
W / cm ² ) for 10 seconds to form a polymer-dispersed liquid crystal, and then an AC electric field of 5 V and 30 Hz is applied to the polymer-dispersed liquid crystal at 80 ° C. for 30 minutes through an ITO electrode to form a liquid crystal cell. completed. The voltage holding ratio of the liquid crystal cell thus completed was 60.5% at 40 ° C.

Example 10 A 3.0% by weight solution of polyimide varnish (manufactured by Nissan Kagaku Co., Ltd .: trade name SE-4110) was prepared. In 100 g of the polyimide solution, 0.2 g of aluminum oxide having a particle size of 0.2 μm and a particle size of 0.
0.2 g of silicon dioxide of 2 μm and calcium oxide of 0.
A solution prepared by mixing 2 g was prepared. Next, indium
Two glass substrates on which transparent electrodes (ITO electrodes) made of tin oxide are formed are prepared, and a polyimide solution prepared by mixing the above-mentioned metal oxide on the ITO electrodes of each glass substrate
0 rpm. After spin coating for 60 seconds, 260
The film was baked at 1 ° C. for 1 hour to form a polyimide coating film mixed with a metal oxide. The film thickness of this polyimide coating is about 80n
It was m.

The two glass substrates thus treated were bonded together with a UV curable resin in which glass fibers having a diameter of 13 μm were dispersed as spacers so that the polyimide coating surfaces face each other, leaving the openings, and the superposed light source. Using a high pressure mercury lamp, the resin was cured and adhered by ultraviolet rays to complete an empty cell. Next, 8.200 g of E8 (manufactured by Merck Japan Ltd.) as a liquid crystal material, 0.600 g of 2 ethylhexyl acrylate and 0.600 g of 2 hydroxyethyl acrylate as a polymer-forming monomer, and Biscoat 828 (Osaka Organic Chemical Industry) as an oligomer. (Made by Co., Ltd.)
Was prepared and 0.060 g of benzyl dimethyl ketal (manufactured by Nippon Kayaku Co., Ltd.) as a photopolymerization initiator was prepared, and the composition comprising the above materials was sufficiently stirred at 50 ° C. It injected at 50 degreeC into the produced empty cell from the opening part. After the injection is completed, the opening is sealed and the temperature is 50 ° C.
Ultraviolet light (intensity: 57mW
/ Cm ² ) for 10 seconds to complete a liquid crystal cell made of polymer dispersed liquid crystal. The voltage holding ratio of the liquid crystal cell thus completed was 63.0% at 40 ° C.

Next, an experimental example for comparison will be described.

(Comparative Example 2) Two glass substrates having transparent electrodes (ITO electrodes) made of indium / tin oxide were prepared, and polyimide varnish (manufactured by Nissan Chemical Industries, Ltd.) was placed on the ITO electrodes of each glass substrate. Product name SE-4110) 3.
0% solution at 2300 rpm. After spin coating for 60 seconds, the coating was baked at 260 ° C. for 1 hour to form a polyimide coating film. The film thickness of this polyimide coating film was about 80 nm. The two glass substrates thus treated were bonded together with a UV curable resin in which glass fibers having a diameter of 13 μm were dispersed as spacers so that the polyimide coating surfaces face each other, leaving the openings, and an ultrahigh pressure mercury lamp was used as a light source. make use of,
The resin was cured and adhered by ultraviolet rays to complete an empty cell. Next, as a liquid crystal material, E8 (Merck Japan Ltd.)
8.200 g, as a polymer-forming monomer, 0.600 g of 2-ethylhexyl acrylate and 0.600 g of 2-hydroxyethyl acrylate, and as an oligomer, 0.6% of Viscoat 828 (manufactured by Osaka Organic Chemical Industry Co., Ltd.).
00 g, 0.060 g of benzyl dimethyl ketal (manufactured by Nippon Kayaku Co., Ltd.) as a photopolymerization initiator were prepared, and the composition comprising the above materials was sufficiently stirred at 50 ° C. to make them compatible with each other, and then the above-mentioned production was performed. It was injected into the empty cell prepared by the method at 50 ° C. through the opening. After the injection is completed, the opening is sealed and the ultra-high pressure mercury lamp is used as a light source to emit ultraviolet rays (intensity: 57 mW / cm ² )
Was irradiated for 10 seconds to complete a liquid crystal cell made of polymer dispersed liquid crystal. The voltage holding ratio of the completed liquid crystal cell is 4
The value was 48.6% at 0 ° C., which was lower than that of the liquid crystal cell described in Example 6 using a polyimide coating film mixed with an adsorbent.

(Comparative Example 3) Two glass substrates having transparent electrodes (ITO electrodes) made of indium / tin oxide were prepared, and polyimide varnish (manufactured by Nissan Kagaku Co., Ltd.) was placed on the ITO electrodes of each glass substrate. Product name SE-4110) 3.
0% solution at 2300 rpm. After spin coating for 60 seconds, the coating was baked at 260 ° C. for 1 hour to form a polyimide coating film. The film thickness of this polyimide coating film was about 80 nm.

The two glass substrates thus treated were bonded together with a UV curable resin in which glass fibers having a diameter of 13 μm were dispersed as spacers so that the polyimide coating surfaces face each other, leaving the openings, and the superposed light source. Using a high pressure mercury lamp, the resin was cured and adhered by ultraviolet rays to complete an empty cell. Next, 8.200 g of E8 (manufactured by Merck Japan Ltd.) as a liquid crystal material, 0.600 g of 2 ethylhexyl acrylate and 0.600 g of 2 hydroxyethyl acrylate as a polymer-forming monomer, and Biscoat 828 (Osaka Organic Chemical Industry) as an oligomer. (Made by Co., Ltd.)
Was prepared, and 0.060 g of benzyl dimethyl ketal (manufactured by Nippon Kayaku Co., Ltd.) as a photopolymerization initiator was prepared, and the composition comprising the materials was sufficiently stirred at 50 ° C. to make them compatible with each other. 50 in the empty cell manufactured by the above-mentioned manufacturing method.
Poured through the opening at ° C. After the injection was completed, an AC electric field of 5 V and 30 Hz was applied to the composition through an ITO electrode at 50 ° C. for 30 minutes. Immediately after the opening was sealed and the electric field was removed, ultraviolet rays (intensity: 57 mW / cm ² ) were irradiated for 10 seconds at 50 ° C. using an ultra-high pressure mercury lamp as a light source to form a liquid crystal cell composed of polymer-dispersed liquid crystal. completed. The voltage holding ratio of the liquid crystal cell thus completed was 51.6% at 40 ° C., which was lower than those of the liquid crystal cells described in Example 7 and Example 8 in which electric field treatment was performed using a polyimide coating film mixed with an adsorbent. showed that.

(Comparative Example 4) Two glass substrates having transparent electrodes (ITO electrodes) made of indium / tin oxide were prepared, and polyimide varnish (manufactured by Nissan Chemical Industries, Ltd.) was placed on the ITO electrodes of each glass substrate. Product name SE-4110) 3.
0% solution at 2300 rpm. After spin coating for 60 seconds, the coating was baked at 260 ° C. for 1 hour to form a polyimide coating film. The film thickness of this polyimide coating film was about 80 nm.

The two glass substrates thus treated were bonded together with a UV curable resin in which glass fibers having a diameter of 13 μm were dispersed as spacers so that the polyimide coating surfaces face each other, leaving the openings, and the superposed light source. Using a high pressure mercury lamp, the resin was cured and adhered by ultraviolet rays to complete an empty cell. Next, 8.200 g of E8 (manufactured by Merck Japan Ltd.) as a liquid crystal material, 0.600 g of 2 ethylhexyl acrylate and 0.600 g of 2 hydroxyethyl acrylate as a polymer-forming monomer, and Biscoat 828 (Osaka Organic Chemical Industry) as an oligomer. (Made by Co., Ltd.)
Was prepared, and 0.060 g of benzyl dimethyl ketal (manufactured by Nippon Kayaku Co., Ltd.) as a photopolymerization initiator was prepared, and the composition comprising the materials was sufficiently stirred at 50 ° C. to make them compatible with each other. 50 in the empty cell manufactured by the above-mentioned manufacturing method.
Poured through the opening at ° C. After the injection is completed, the opening is sealed and the ultra-high pressure mercury lamp is used as a light source to emit ultraviolet rays (strength: 57 m
W / cm ² ) for 10 seconds to form a polymer-dispersed liquid crystal, and then an AC electric field of 5 V and 30 Hz is applied to the polymer-dispersed liquid crystal at 80 ° C. for 30 minutes through an ITO electrode to form a liquid crystal cell. completed. The voltage holding ratio of the liquid crystal cell thus completed was 50.0% at 40 ° C., and the liquid crystal cell of Example 9 was subjected to an electric field treatment after forming a polymer dispersed liquid crystal using a polyimide coating film mixed with an adsorbent. Showed a lower value than

Although the temperature at which the electric field treatment is carried out is not limited, when the electric field treatment is carried out before the polymerization of the polymerizable material as in the above-mentioned embodiment of the present invention, the composition of the liquid crystal and the polymerizable material is used. When the polymer-dispersed liquid crystal formed by completing the polymerization of the polymerizable material is subjected to an electric field treatment, the temperature at which the liquid-crystal used for the polymer-dispersed liquid crystal is isotropic. The voltage holding ratio of the liquid crystal cell is higher when the electric field treatment is carried out at. At low temperatures, the migration of impurities is poor and the adsorption to adsorbents and coatings is poor, and as a result, the voltage holding ratio does not increase so much. The intensity and frequency of the electric field to be subjected to the electric field treatment and the application time are not limited to those shown in the examples, and can be appropriately changed and used. Further, a DC electric field may be applied in a range where materials such as liquid crystal and a polymerizable material are not deteriorated as well as AC.

As the coating film provided on the electrodes of the substrate, the same coating film may be used on the substrates on both sides as described in the above embodiment, or different coating films may be used on the substrates on both sides. Further, as the adsorbent mixed in the coating film, different adsorbents may be mixed in the coating films on both the substrates. Further, the coating material is not limited to the polyimide described in the examples, and various organic materials can be used. Further, these coating films may be subjected to orientation treatment by rubbing treatment or the like. In this example, the thickness of these coating films was 80 nm, but the present invention is not limited to this. These coating films can be used even if they are provided only on one side of the substrate.

The liquid crystal material used for the polymer dispersed liquid crystal is
It is not limited to E8 described in the above embodiment,
Other cyano liquid crystals, various nematic liquid crystals such as fluorine liquid crystals, and cholesteric liquid crystals may be used. In this example, the polymer dispersed liquid crystal is described by using the polymer dispersed liquid crystal in which the liquid crystal phase is separated into droplets, but the invention is not limited to this. The same effect can be achieved with a polymer-dispersed liquid crystal in which the liquid crystal forms a continuous phase. Further, in this example, the ratio of the liquid crystal in the polymer dispersed liquid crystal is set to about 82% by weight, but it is not limited to this. As the polymer-forming monomer, 2 ethylhexyl acrylate or 2 hydroxyethyl acrylate was used this time, but it is not limited thereto. Neopentyl glycol acrylate, hexanediol diacrylate, diethylene glycol diacrylate, tripropylene glycol diacrylate. , Commercially available acrylic monomers such as polyethylene glycol diacrylate and trimethylolpropane triacrylate, and widely applicable commercial products other than acrylic monomers. The oligomer is not limited to Viscoat 828 (manufactured by Osaka Organic Chemical Industry Co., Ltd.) shown in the examples.

Also, the polymerization initiator is not limited to benzyl dimethyl ketal (manufactured by Nippon Kayaku Co., Ltd.), and Darocur 1173 manufactured by Merck Co., Ltd., Irgacure 184 manufactured by Ciba-Gaiky Co., Ltd., Irgacure 651, etc. But it's okay.

Further, the polymer material used is not limited to the photo-curable resin shown in the examples, and may be a thermosetting resin or a thermoplastic resin.

[0058]

As is apparent from the above description,
According to the present invention, an adsorbent composed of a metal oxide or the like is mixed in a polymer-dispersed liquid crystal, and an electric field is applied to the polymer-dispersed liquid crystal before or after the polymerization of a polymerizable material is completed. As a result, the charge retention characteristics of the liquid crystal optical element can be improved.

Instead of mixing the adsorbent in the polymer-dispersed liquid crystal, a substrate in which the adsorbent is mixed is provided on the substrate sandwiching the polymer-dispersed liquid crystal, and a substrate of the polymerizable material is used. Even if an electric field is applied to the polymer-dispersed liquid crystal before or after the polymerization, a liquid crystal optical element having a good charge retention property can be realized.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a configuration of a liquid crystal optical element produced by using the polymer-dispersed liquid crystal according to claims 1 to 4 of the present invention.

FIG. 2 is a diagram schematically showing a method for producing a liquid crystal optical element using the polymer-dispersed liquid crystal according to claims 5 to 10 of the present invention.

FIG. 3 is a diagram schematically showing a method for producing a liquid crystal optical element using the polymer dispersed liquid crystal according to claims 11 to 15 of the present invention.

FIG. 4 is a cross-sectional view showing a configuration of a liquid crystal optical element produced by using the polymer-dispersed liquid crystal according to claims 16 to 19 of the present invention.

FIG. 5 is a diagram schematically showing a method for producing a liquid crystal optical element using the polymer-dispersed liquid crystal according to claims 20 to 25 of the present invention.

FIG. 6 is a diagram schematically showing a method for producing a liquid crystal optical element using the polymer-dispersed liquid crystal according to claim 26 to claim 30 of the present invention.

FIG. 7 is a schematic view showing a display principle of a liquid crystal optical element manufactured by using polymer-dispersed liquid crystal.

FIG. 8 is a diagram illustrating a method of measuring a voltage holding ratio.

[Explanation of symbols]

11 Upper Substrate 46 Adsorbent 12 Lower Substrate 47 Coating Film Containing Adsorbent 13 Electrode 51 Upper Substrate 14 Spacer and Seal Resin 52 Lower Substrate 15 Polymer Dispersed Liquid Crystal 53 Electrode 16 Adsorbent 54 Spacer and Seal Resin 21 Upper Substrate 55 Composition 22 Lower substrate 56 Adsorbent 23 Electrode 57 Electric field 24 Spacer and sealing resin 58 Coating film containing adsorbent 25 Composition 61 Upper substrate 26 Adsorbent 62 Lower substrate 27 Electric field 63 Electrode 31 Upper substrate 64 Spacer Sealing resin 32 Lower substrate 65 Polymer dispersed liquid crystal 33 Electrode 66 Adsorbent 34 Spacer and sealing resin 67 Electric field 35 Polymer dispersed liquid crystal 68 Coating film containing adsorbent 36 Adsorbent 71 Electrode 37 Electric field 72 Incident light 41 Upper substrate 73 Scattered light 42 Lower substrate 74 Liquid crystal 43 Electrode 75 Polymer phase 44 P o and the seal resin 76 transmitted light 45 PDLC

Claims (30)

[Claims] 1. A liquid crystal optical element comprising a polymer-dispersed liquid crystal mixed with an adsorbent. 2. The liquid crystal optical element according to claim 1, wherein the adsorbent is a metal oxide. 3. The liquid crystal optical element according to claim 2, wherein the metal oxide is a metal oxide having both acid points and basic points. 4. The liquid crystal optical element according to claim 2, wherein the metal oxide is a mixture of two kinds of a metal oxide having an acid point and a metal oxide having a basic point. 5. A mixture of a composition comprising a liquid crystal and a polymerizable material and an adsorbent is sandwiched between a pair of upper and lower substrates having transparent electrodes provided on at least one substrate, and the mixture is passed through the electrodes to form the mixture. A method for producing a liquid crystal optical element, which comprises applying an electric field and then removing the electric field to complete the polymerization of the polymerizable material. 6. A mixture of a composition comprising a liquid crystal and a polymerizable material and an adsorbent is sandwiched between a pair of upper and lower substrates having transparent electrodes provided on at least one substrate, and the mixture is passed through the electrodes to form the mixture. A method for producing a liquid crystal optical element, characterized in that the polymerization of the polymerizable material is completed while applying an electric field. 7. The adsorbent mixed with the composition comprising liquid crystal and a polymerizable material is a metal oxide.
Alternatively, the method for manufacturing a liquid crystal optical element according to claim 6. 8. The method for producing a liquid crystal optical element according to claim 7, wherein the metal oxide is a metal oxide having both acid points and basic points. 9. The method for producing a liquid crystal optical element according to claim 7, wherein the metal oxide is a mixture of two kinds of a metal oxide having an acid point and a metal oxide having a basic point. 10. The temperature at which an electric field is applied to a mixture obtained by mixing an adsorbent with a composition comprising liquid crystal and a polymerizable material is a temperature at which the composition exhibits a compatible state. 5. The method for producing a liquid crystal optical element according to claim 5 or claim 6. 11. A mixture of a composition comprising a liquid crystal and a polymerizable material and an adsorbent is sandwiched between a pair of upper and lower substrates having transparent electrodes provided on at least one substrate, and the polymerizable material A method for producing a liquid crystal optical element, comprising polymerizing, sandwiching a polymer-dispersed liquid crystal containing an adsorbent between substrates, and then applying an electric field to the polymer-dispersed liquid crystal through electrodes. 12. The method for producing a liquid crystal optical element according to claim 11, wherein the adsorbent mixed with the composition comprising liquid crystal and a polymerizable material is a metal oxide. 13. The method for producing a liquid crystal optical element according to claim 12, wherein the metal oxide is a metal oxide having both acid points and basic points. 14. The method for producing a liquid crystal optical element according to claim 12, wherein the metal oxide is a mixture of two kinds of a metal oxide having an acid point and a metal oxide having a basic point. 15. The method for producing a liquid crystal optical element according to claim 11, wherein the temperature at which an electric field is applied to the polymer-dispersed liquid crystal containing an adsorbent is a temperature at which the liquid crystal exhibits isotropicity. . 16. A liquid crystal optical element in which a polymer-dispersed liquid crystal is sandwiched between a pair of upper and lower substrates having transparent electrodes provided on at least one substrate, and the substrate is coated with an adsorbent mixed. A liquid crystal optical element, which is a substrate having a structure provided with a film. 17. The liquid crystal optical element according to claim 16, wherein the adsorbent is a metal oxide. 18. The liquid crystal optical element according to claim 17, wherein the metal oxide is a metal oxide having both acid points and basic points. 19. The liquid crystal optical element according to claim 17, wherein the metal oxide is a mixture of two kinds of a metal oxide having an acid point and a metal oxide having a basic point. 20. A composition comprising a liquid crystal and a polymerizable material provided on a pair of upper and lower substrates having transparent electrodes provided on at least one substrate with a coating film mixed with an adsorbent, between the substrates. A method for producing a liquid crystal optical element, characterized in that after the electric field is applied to the composition through the electrodes, the polymerization of the polymerizable material is completed after the electric field is removed. 21. A composition composed of a liquid crystal and a polymerizable material is provided between electrodes of a pair of upper and lower substrates having transparent electrodes provided on at least one substrate, and a coating film is provided between the substrates. A method for producing a liquid crystal optical element, characterized in that the polymerization of the polymerizable material is completed while an electric field is applied to the composition through the electrodes by sandwiching. 22. The method of manufacturing a liquid crystal optical element according to claim 20, wherein the adsorbent mixed with the coating film provided on the electrode is a metal oxide. 23. The method for producing a liquid crystal optical element according to claim 22, wherein the metal oxide is a metal oxide having both acid points and basic points. 24. The method for producing a liquid crystal optical element according to claim 22, wherein the metal oxide is a mixture of two kinds of a metal oxide having an acid point and a metal oxide having a basic point. 25. The liquid crystal according to claim 20 or 21, wherein the temperature at which an electric field is applied to the composition comprising the liquid crystal and the polymerizable material is a temperature at which the composition exhibits compatibility. Optical element manufacturing method. 26. A composition comprising a liquid crystal and a polymerizable material provided on a pair of upper and lower substrates having transparent electrodes provided on at least one substrate with a coating film mixed with an adsorbent, between the substrates. And a polymer-dispersed liquid crystal is sandwiched between the substrates, and then an electric field is applied to the polymer-dispersed liquid crystal through electrodes to produce a liquid crystal optical element. 27. The method for producing a liquid crystal optical element according to claim 26, wherein the adsorbent mixed with the coating film provided on the electrode is a metal oxide. 28. The method for producing a liquid crystal optical element according to claim 27, wherein the metal oxide is a metal oxide having both acid points and basic points. 29. The method for producing a liquid crystal optical element according to claim 27, wherein the metal oxide is a mixture of two kinds of a metal oxide having an acid site and a metal oxide having a basic site. 30. The method for producing a liquid crystal optical element according to claim 26, wherein the temperature at which an electric field is applied to the polymer dispersed liquid crystal is a temperature at which the liquid crystal exhibits isotropicity.