JP2003147221A - Polymer gel composition, and optical element using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a polymer gel composition which can largely change its optical scattering property, reflection coefficient, light absorption, and the like, in response to an electric field, has a stable repeating characteristic, and can be applied to transmission type elements in a simple structure, and to provide an optical element using the polymer gel composition. SOLUTION: The polymer gel composition is characterized by having a liquid and an antistatic polymer gel which absorbs or releases the liquid in response to an electric field to change the volume. The optical element uses this polymer gel composition.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a polymer gel composition which can be widely used as an optical element such as a light control glass, a light control element and a display element and an optical element using the same, and more specifically, it is reversible by an electric field. And a polymer gel composition having various properties such as color change, light scattering, control of transmitted light amount and reflected light amount in a wide wavelength range, various color tones, and display of various patterns. The present invention relates to an optical element using a polymer gel composition.

[0002]

2. Description of the Related Art The need for color display systems and large-area display systems has increased with the development of an advanced information society. CRT, liquid crystal, E
Display technologies such as L, LED, and plasma have been developed. In addition to these self-luminous systems, the development of a reflective display system that consumes less power and has less discomfort to the human eye is under consideration. As a reflective display system, reflective liquid crystal technology and the like are becoming dominant.

On the other hand, an inexpensive large area color display system,
Alternatively, there is a great need for an inexpensive large-area display system, but the promising technology to realize it is not established yet. Electrophoresis, twist balls and the like are known as candidate materials. Further, a current display technology using a stimuli-responsive polymer gel is known.

As a current display technology using polymer gel,
The following techniques are disclosed. JP-A-4-134
Japanese Patent Laid-Open No. 325 and Japanese Patent Laid-Open No. 188354/1993 propose an element that changes the light scattering state by swelling / shrinking of a polymer gel by energization, and performs light control and display by transparent / white turbidity. Japanese Patent Application Laid-Open No. 4-274480 proposes an optical element that utilizes the swelling / shrinkage of a colored polymer gel to which a dye is covalently bound due to energization. This publication provides a display element that changes the optical density by increasing / decreasing the absorption cross-section of light by swelling / contracting of a polymer gel by energization. Japanese Patent Application Laid-Open No. 9-160081 proposes an optical element in which a colored substrate or the like and a colored polymer gel are combined. This publication discloses an optical element technique for increasing or decreasing the optical density by changing the ratio of covering a colored substrate or the like with a colored polymer gel due to bending, stretching, swelling / shrinkage, etc. of the colored polymer gel due to electrical stimulation. JP 61-149
Japanese Patent No. 926 proposes an optical element composed of a composition in which a polymer gel that swells and contracts when energized is combined with a colored liquid in which a pigment is dispersed in a liquid. This publication provides a technique in which a colored liquid is moved by a change in the shape of a polymer gel due to energization, and a change in the absorption amount of light of the colored liquid that occurs at that time is used. Japanese Patent Fair 7-95172
JP-A-11-236559 and JP-A-11-236559 also disclose a technique in which a conductive polymer or the like is applied as an electrode to prevent electrolysis of a liquid caused by energization and to prevent generation of bubbles due to electrolysis.

However, the dimming / display element technology disclosed in the above publication has various points to be improved. For example, JP-A-4-134325, JP-A-5-188354, JP-A-4-274480, JP-A-9-160081, and JP-A-61-161.
The device disclosed in Japanese Patent No. 149926 has a problem in that the solvent for holding the polymer gel is electrolyzed by energization and bubbles are generated, so that the display quality and the dimming property are deteriorated at every energization. there were. Japanese Patent Fair 7-9517
No. 2, there is a problem that sufficient display contrast, reflectance, and amount of light absorption cannot be changed due to the unique color of the conductive polymer or the like formed on the electrodes. Further, there remains a problem that the conductive polymer is not excellent in durability against electric current as an element. Furthermore, it is difficult to apply it to a transmissive display device due to its inherent color and device structure such as conductive polymer. In Japanese Patent Application Laid-Open No. 11-236559, as in Japanese Patent Publication No. 7-95172, a conductive polymer or the like is used, so that sufficient display contrast, reflectance, and change amount of light absorption can be obtained. There is a problem in that it is inferior in current carrying stability. Moreover, since the electrode structure is complicated, the manufacturing cost of the device is increased.

[0006] Such a dimming / display element technology by energization responds to changes in the ion concentration in the solvent (swelling liquid).
The technology that causes the volume change of the polymer gel is common, and as described above, the problem that the display quality and the dimming characteristic are impaired at every energization due to the electrolysis and generation of bubbles and the transmission type It is difficult to apply it to the display element and the electrode structure is complicated, which leads to high manufacturing cost of the element, and the present situation is that improvement is desired.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the various problems in the prior art and achieve the following objects. That is, the object of the present invention is to obtain a large amount of change in light scattering rate, reflectance, absorption amount of light, etc. according to an electric field, and also to have stable repeatability, and to provide a transmission type display with a simple structure. To provide a polymer gel composition applicable to an element and an optical element using the same.

[0008]

The above problems can be solved by the following means. That is, the present invention is a polymer gel composition including <1> liquid and a chargeable polymer gel that changes in volume by absorbing and releasing the liquid according to an electric field. <2> The polymer gel composition according to <1>, wherein the liquid is an insulating liquid. <3> The polymer gel composition according to <1> or <2>, wherein the volume resistivity of the liquid is 10 ³ Ωcm or more. <4> The polymer gel composition according to any one of <1> to <3>, wherein the chargeable polymer gel is an ionic polymer gel. <5> The above-mentioned <1> to <3>, wherein the chargeable polymer gel is an ionic polymer gel containing a charging agent.
The polymer gel composition according to any one of 1. <6> The above-mentioned <1> to <3>, wherein the chargeable polymer gel is a nonionic polymer gel containing a charging agent.
> The polymer gel composition according to any one of the items above. <7> The polymer gel composition according to any one of <1> to <6>, wherein the chargeable polymer gel contains a light control material. <8> The polymer gel composition according to <5> or <6>, wherein the charging agent is a light control material. <9> The polymer gel composition according to any one of <1> to <8>, wherein the chargeable polymer gel has a spherical shape. <10> An optical element comprising the polymer gel composition according to any one of <1> to <9>. <11> The optical element according to <10>, further including an electric field applying unit that applies an electric field to the polymer gel composition. <12> The optical element according to <10>, further comprising an electrode for applying an electric field to the polymer gel composition, wherein the chargeable polymer gel is immobilized on the electrode. .

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail. The polymer gel composition of the present invention is characterized by having a liquid and a chargeable polymer gel that changes in volume by absorbing and releasing the liquid according to an electric field. The polymer gel composition of the present invention has a configuration including a chargeable polymer gel and a liquid, and can cause a large reversible volume change in response to an electric field. Also, when a light control material such as a pigment or a dye is dispersed in a chargeable polymer gel, it is possible to greatly change the optical characteristics by changing the absorption cross section during swelling / shrinking. It can be applied to optical elements such as light control, display elements and the like. It is considered that this volume change is caused by the interaction between the chargeable polymer gel and the electric field. In addition, the polymer gel composition of the present invention has a configuration including a chargeable polymer gel and a liquid, in which generation of bubbles due to electrolysis of the liquid due to an electrode reaction is suppressed, and dimming characteristics are impaired at each energization. And has excellent repeatability. Further, since it is not necessary to use a conductive polymer or the like, the light scattering rate, reflectance, light absorption amount, etc. can be greatly changed. Further, it has a simple element structure and can be applied to optical elements such as transmissive or laminated color display elements and light control elements.

The chargeable polymer gel will be described. Specifically as the chargeable polymer gel, an ionic polymer gel,
It can be selected from an ionic polymer gel containing a charging agent and a nonionic polymer gel containing a charging agent. Hereinafter, preferable specific examples of each polymer gel will be listed.
In the description of these specific examples, the description such as (meth) acrylate is an expression that includes both an acrylate and a methacrylate (methacrylate).

<1> Ionic Polymer Gel Examples of the ionic polymer gel include crosslinked poly (meth) acrylic acid and its salts, and (meth) acrylic acid and (meth).
Crosslinked products of copolymers with acrylamide, hydroxyethyl (meth) acrylate, (meth) acrylic acid alkyl ester and the like, salts thereof, crosslinked products of polymaleic acid and salts thereof, maleic acid and (meth) acrylamide, hydroxyethyl (meth) ) Acrylate, crosslinked product of copolymer with (meth) acrylic acid alkyl ester and the like, salt thereof, crosslinked product of polyvinyl sulfonic acid, vinyl sulfonic acid and (meth) acrylamide, hydroxyethyl (meth) acrylate, (meth) acrylic Cross-linked products of copolymers with acid alkyl esters, polyvinyl benzene sulfonic acid cross-linked products and salts thereof, vinyl benzene sulfonic acid and (meth) acrylamide, hydroxyethyl (meth) acrylate, (meth) acrylic acid alkyl esters, etc. Cross-linked product of its copolymer and its salt Crosslinked products of polyacrylamidoalkylsulfonic acid and salts thereof, crosslinked products of copolymers of acrylamidoalkylsulfonic acid and (meth) acrylamide, hydroxyethyl (meth) acrylate, alkyl (meth) acrylate, etc. Dimethylaminopropyl (meth) acrylamide cross-linked product and its hydrochloride, dimethylaminopropyl (meth) acrylamide and (meth) acrylic acid, (meth) acrylamide,
Crosslinked products of copolymers with hydroxyethyl (meth) acrylate, (meth) acrylic acid alkyl ester and the like, quaternary compounds and salts thereof, polydimethylaminopropyl (meth)
Cross-linked product of acrylamide and polyvinyl alcohol complex, quaternary compound or salt thereof, cross-linked product of polyvinyl alcohol-poly (meth) acrylic acid complex and its salt, cross-linked product of carboxyalkyl cellulose salt, poly (meta ) Partial hydrolyzates of acrylonitrile cross-linked products, salts thereof, and the like. These ionic polymer gels are produced by adding a crosslinking agent, or irradiating the polymer with radiation such as electron rays and γ rays, heating, and by three-dimensionally crosslinking by adding a peroxide. can do.

<2> Ionic Polymer Gel Containing Charging Agent The ionic polymer gel constituting the ionic polymer gel containing a charging agent is described in the above <1> Ionic polymer gel. Ionic polymer gels similar to those mentioned above can be mentioned. On the other hand, as the charging agent to be contained in the ionic polymer gel, various amphipathic (high) molecules, nigrosine compounds, alkoxylated amines, quaternary ammonium salts, alkylamides, phosphorus and tungsten simple substances and compounds , Molybdenum chelate pigments, hydrophobic silica, borons, halogen compounds, metal salts of monoazo dyes, salicylic acid, alkylsalicylic acid, dialkylsalicylic acid, metal complexes of naphthoic acid, chlorinated polyolefins, chlorinated polyesters, polyesters with excess acid groups, copper Examples thereof include sulfonylamine of phthalocyanine, oil black, metal salt of naphthenic acid, metal salt of fatty acid and soap of resin acid.
The addition amount of the charging agent contained in the ionic polymer gel is
A range of 2% by mass to 70% by mass is preferable. Further, the charging agent may be a light control material described later. At this time, the preferable concentration of the light control material contained in the ionic polymer gel is in the range of 2% by mass to 70% by mass, particularly preferably in the range of 5% by mass to 50% by mass. Further, in order to improve the response of the ionic polymer gel to the electric field, a charging agent other than the light control material may be separately contained in the ionic polymer gel. At this time, the addition amount of the charging agent other than the light control material contained in the ionic polymer gel is preferably in the range of 2% by mass to 70% by mass.

<3> Nonionic Polymer Gel Containing Charging Agent Nonionic polymer gel is defined as a polymer gel having no ionic dissociation group in the polymer chain. Specifically, a crosslinked product of a homopolymer composed of one or more kinds of monomers selected from the group of monomers listed below and a crosslinked product of a copolymer composed of two or more kinds of monomers are preferable. -Monomers- (meth) acrylonitrile, (meth) acrylic acid alkyl ester, (meth) acrylic acid dialkylaminoalkyl ester, (meth) acrylamide, ethylene, propylene, butadiene, isoprene, isobutylene, N
-Dialkyl-substituted (meth) acrylamide, vinylpyridine, vinylamine, allylamine, styrene, vinylcarbazole, vinylpyrrolidone, styrene, styrene derivative, ethylene glycol di (meth) acrylate,
Glyceryl (meth) acrylate, polyethylene glycol mono (meth) acrylate, vinyl chloride, vinylidene chloride, ethylene glycol di (meth) acrylate,
Examples thereof include methylenebisacrylamide, isoprene, butadiene, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, butanediol di (meth) acrylate, and hexanediol di (meth) acrylate. In addition, crosslinked polyester polymers, crosslinked polyvinyl acetal derivatives, crosslinked polyurethane polymers, crosslinked polyurea polymers, crosslinked polyether polymers,
A cross-linked body of a polyamide-based polymer and a cross-linked body of a polycarbonate-based polymer can be preferably used. Nonionic polymer gels can be prepared by adding a cross-linking agent or by adding electron beam, γ
It can be produced by irradiation with radiation such as rays, heating, and three-dimensional crosslinking by adding a peroxide. On the other hand, examples of the charging agent contained in the nonionic polymer gel include the same as those described in the above <2> Ionic polymer gel containing the charging agent. The addition amount of the charging agent contained in the nonionic polymer gel is preferably in the range of 2% by mass to 70% by mass.
Further, the charging agent may be a light control material described later. At this time, the preferable concentration of the light control material contained in the nonionic polymer gel is in the range of 2% by mass to 70% by mass, particularly preferably in the range of 5% by mass to 50% by mass. Further, in order to improve the response of the nonionic polymer gel to the electric field, a charging agent other than the light control material may be separately contained in the nonionic polymer gel.
At this time, the addition amount of the charging agent other than the light control material contained in the nonionic polymer gel is preferably in the range of 2% by mass to 70% by mass.

For the chargeable polymer gel, when the polymer gel composition of the present invention is used for optical elements and display elements,
It is preferable to add / contain a light control material. Although described above, the light control material may be a charging agent.

Specific examples of the light control material include dyes, pigments and light scattering materials. Further, it is preferable that the light control material is physically or chemically immobilized in the chargeable polymer gel.

Preferred specific examples of the dyes include, for example, black nigrosine dyes and azo dyes such as red, green, blue, cyan, magenta and yellow color dyes, anthraquinone dyes, indigo dyes and phthalocyanine dyes. Examples thereof include dyes, carbonium dyes, quinone imine dyes, methine dyes, quinoline dyes, nitro dyes, benzoquinone dyes, naphthoquinone dyes, naphthalimide dyes, and verinone dyes, and those having a high light absorption coefficient are particularly desirable.
For example, C.I. I. Direct Yellow 1,8,11,1
2, 24, 26, 27, 28, 33, 39, 44, 5
0,58,85,86,87,88,89,98,15
7, C.I. I. Acid Yellow 1,3,7,11,1
7, 19, 23, 25, 29, 38, 44, 79, 12
7, 144, 245, C.I. I. Basic Yellow 1,
2, 11, 34, C.I. I. Food Yellow 4, C.I. I.
Reactive Yellow 37, C.I. I. Solvent Yellow 6,9,17,31,35,100,102,10
3,105, C.I. I. Direct Red 1, 2, 4,
9, 11, 13, 17, 20, 23, 24, 28, 3
1, 33, 37, 39, 44, 46, 62, 63, 7
5, 79, 80, 81, 83, 84, 89, 95, 9
9,113,197,201,218,220,22
4,225,226,227,228,229,23
0, 231, C.I. I. Acid Red 1, 6, 8, 9,
13, 14, 18, 26, 27, 35, 37, 42, 5
2,82,85,87,89,92,97,106,1
11, 114, 115, 118, 134, 158, 18
6,249,254,289, C.I. I. Basic Red 1, 2, 9, 12, 14, 17, 18, 37, C.I.
I. Hood Red 14, C.I. I. Reactive red 2
3,180, C.I. I. Solvent Red 5,16,1
7, 18, 19, 22, 23, 143, 145, 14
6,149,150,151,157,158, C.I.
I. Direct Blue 1,2,6,15,22,25,
41, 71, 76, 78, 86, 87, 90, 98, 1
63, 165, 199, 202, C.I. I. Acid Blue 1,7,9,22,23,25,29,40,41,
43, 45, 78, 80, 82, 92, 93, 127,
249, C.I. I. Basic Blue 1, 3, 5, 7,
9, 22, 24, 25, 26, 28, 29, C.I. I. Food Blue 2, C.I. I. Solvent Blue 22,63,
78, 83-86, 191, 194, 195, 104,
C. I. Direct Black 2,7,19,22,2
4, 32, 38, 51, 56, 63, 71, 74, 7
5,77,108,154,168,171, C.I. I.
Acid Black 1,2,7,24,26,29,3
1,44,48,50,52,94, C.I. I. Basic Black 2, 8, C.I. I. Food black 1, 2,
C. I. Reactive Black 31, C.I. I. Food violet 2, C.I. I. Solvent violet 31,
33, 37, C.I. I. Solvent Green 24, 25,
C. I. Solvent Brown 3, 9 and the like can be mentioned. These dyes may be used alone or in a mixture to obtain a desired color.

As the dye, a so-called reactive compound capable of reacting with a dye or a chargeable polymer gel having a structure having a polymerizable group such as an unsaturated double bond group for immobilizing the dye on the chargeable polymer gel. A dye or the like is preferably used. The preferred concentration of the dye contained in the chargeable polymer gel is in the range of 2% by mass to 70% by mass, particularly preferably 5% by mass to 50% by mass. When it is less than 2% by mass, the light control effect is lowered, and when it is more than 70% by mass, it becomes difficult to obtain a material having good strength.

Preferable specific examples of the pigment and the light-scattering material include black pigments such as bronze powder, titanium black, various carbon blacks (channel black, furnace black, etc.), white pigments such as titanium oxide, and metal oxides such as silica. Materials, light-scattering materials such as calcium carbonate and metal powder, color pigments such as phthalocyanine-based cyan pigments,
Benzidine-based yellow pigments, rhodamine-based magenta pigments, or other anthraquinone-based, azo-based,
Examples include various pigments and light scattering materials such as azo metal complexes, phthalocyanine-based, quinacridone-based, perylene-based, indigo-based, isoindolinone-based, quinacridone-based, allylamide-based, and zinc sulfide.

For example, as the yellow pigment, compounds represented by condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds and allylamide compounds are used. More specifically,
C. I. Pigment Yellow 12, 13, 14, 15,
17, 62, 74, 83, 93, 94, 95, 109,
110,111,128,129,147,168 etc. are used suitably. Examples of magenta pigments include condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinones, quinacridone compounds, basic dye lake compounds,
A naphthol compound, a benzimidazolone compound, a thioindigo compound, and a perylene compound are used. More specifically, C.I. I. Pigment Red 2, 3, 5, 6, 7,
23, 48; 2, 48; 3, 48; 4, 57; 1, 8
1; 1, 144, 146, 166, 169, 177, 1
84,185,202,206,220,221,25
4 is particularly preferred. As the cyan pigment, a copper phthalocyanine compound and its derivative, an anthraquinone compound, a basic dye lake compound and the like can be used. Specifically, for example, as a pigment, C.I. I. Pigment Blue 1,7,15,15: 1,15: 2,15; 3,15:
4,60,62,66 etc. can be used especially suitably.

The average particle size of the primary particles is preferably 0.001 μm to 1 μm, and the particle size of the pigment and the light scattering material is preferably
Particularly, those having a thickness of 0.01 μm to 0.5 μm are preferable. This is because if the particle size is less than 0.01 μm, the chargeable polymer gel may easily flow out, and if it exceeds 0.5 μm, the color developing property may be deteriorated.

It is preferable that the pigment and the light-scattering material are contained in the chargeable polymer gel as uniformly as possible in a dispersed state and do not flow out from the chargeable polymer gel. For that purpose, the crosslink density of the chargeable polymer gel is optimized so that the pigment and the light scattering material are physically confined in the polymer network, and the electrical, ionic and other physical interaction with the chargeable polymer gel is performed. It is preferable to use a pigment or a light scattering material having a high action, or to use a pigment or a light scattering material whose surface is chemically modified. Specifically, for example, as a pigment or a light-scattering material whose surface is chemically modified, an unsaturated group such as a vinyl group or a group such as an unpaired electron (radical) that chemically bonds to a charged polymer gel is introduced on the surface. Examples thereof include those obtained by grafting a polymer material, and those obtained by coating or encapsulating the surface with a polymer or the like.

The concentrations of the pigment and the light-scattering material are generally preferably 2% by mass to 70% by mass with respect to the chargeable polymer gel. When it is less than 2% by mass, the light control effect is deteriorated, and when it is more than 70% by mass, it may be difficult to obtain a material having good strength.

The chargeable polymer gel containing such a light control material can be prepared by uniformly dispersing and mixing the light control material in the polymer before crosslinking, followed by crosslinking and a polymer precursor monomer composition during polymerization. It can be manufactured by a method in which a light control material is added to and polymerized. When a pigment or a light scattering material is added during polymerization, a pigment or a light scattering material having a polymerizable group or an unpaired electron (radical) may be used to chemically bond to the chargeable polymer gel as described above. It is preferably carried out. Further, the light control material is preferably dispersed as uniformly as possible in the chargeable polymer gel. In particular, it is desirable to use a mechanical kneading method, a stirring method, or a dispersant to uniformly disperse the particles in the polymer. Furthermore, as described above, it is also possible to use the light control materials listed above as a charging agent to be contained in the chargeable polymer gel. Charge can be imparted to the chargeable polymer gel by contact charging between the dimming material contained in the chargeable polymer gel and the solvent, but it is more preferable to impart a charge imparting function to the surface of the dimming material. preferable. As a method of imparting a charge imparting function to the surface of the light control material, the surface of the light control material may be an amino group, an ammonium group, a halogen group, a hydroxyl group, a carboxyl group, a sulfonic acid group, a phosphoric acid group, an amide group, a thiol group, or the like. May be introduced.

The chargeable polymer gel is preferably in the form of particles. The particles may be spherical, cubic, ellipsoidal, polyhedral, porous, fibrous, star-shaped, needle-shaped, hollow, ring-shaped or the like. Among them, the spherical shape is particularly preferable from the viewpoint of being able to swell and shrink the chargeable polymer gel particles isotropically. The size of the chargeable polymer gel particles is preferably in the range of 0.1 μm to 200 μm, more preferably 1 μm to 100 μm in average particle size in the liquid-free state. Particle size is 0.1μ
When it is m or less, handling of particles may be difficult, and excellent optical properties may not be obtained. On the other hand, if the particle size is larger than 100 μm, problems such as slow migration speed may occur.

These chargeable polymer gel particles are obtained by pulverizing the chargeable polymer gel by a physical crushing method or by polymerizing the polymer before crosslinking by a physical crushing method or a chemical crushing method, and then crosslinking the polymer. It can be produced by a general method such as a method of forming a gel by gelling, or a particle polymerization method such as an emulsion polymerization method, a suspension polymerization method, and a dispersion polymerization method.

The absorption amount of the liquid when the chargeable polymer gel is swollen is preferably in the range of 2 g / g to 200 g / g.
If it is less than 2 g / g, it may be easy to suppress aggregation between chargeable polymer gels (particles) and reduce color purity.
If it exceeds, the concentration of the light control material in the chargeable polymer gel may be lowered, and the light control contrast may be lowered.

The liquid will be described. The liquid has a volume resistance value of preferably 10 ³ Ωcm or more, more preferably 10 ⁷ Ωcm to 10 ¹⁹ Ωcm, and further preferably 10 ¹⁰ to 10 ¹⁹ Ωcm. With such a volume resistance value, the generation of bubbles due to the electrolysis of the liquid due to the electrode reaction is more effectively suppressed, the dimming characteristic is not impaired at each energization, and excellent repeated stability is obtained. It is possible to impart sex. From this point of view, it is particularly preferable to use an insulating liquid as the liquid. The liquid may be added with an acid, an alkali, a salt, a dispersion stabilizer, a stabilizer for the purpose of preventing oxidation or absorbing ultraviolet rays, an antibacterial agent, an antiseptic agent, etc. It is preferable to add it so as to be within the range of the resistance value.

Specific examples of the liquid include hexane, cyclohexane, toluene, xylene, decane, hexadecane, kerosene, paraffin, isoparaffin, silicone oil, dichloroethylene, trichloroethylene,
Perchlorethylene, high-purity petroleum, ethylene glycol, alcohols, ethers, esters, dimethylformamide, dimethylacetamide, dimethylsulfoxide, N-methylpyrrolidone, 2-pyrrolidone, N-
Methylformamide, acetonitrile, tetrahydrofuran, propylene carbonate, ethylene carbonate, benzine, diisopropylnaphthalene, olive oil, isopropanol, trichlorotrifluoroethane, tetrachloroethane, dibromotetrafluoroethane, and mixtures thereof can be preferably used. Also,
Water (so-called pure water) can be preferably used by removing the impurities so that the volume resistivity falls within the above range.

In the polymer gel composition of the present invention, when a liquid having a refractive index difference of 0.01 or less between the liquid and the chargeable polymer gel (chargeable polymer gel containing the light control material) is used. In addition, the light scattering property at the particle interface is reduced, and the color purity can be improved, which is desirable. By using a combination of such low-refractive-index differences, when the colored charging polymer gel particles are used, the incident light is not scattered even at the time of color development and is transmitted, so It can also be used as an optical element.

The polymer gel composition of the present invention comprises a chargeable polymer gel and a liquid as a polymer (so-called matrix resin).
The application form can be expanded by solidifying by dispersing it in the inside or encapsulating it with a polymer film. These techniques are disclosed in JP-A-11-228850.
It can be carried out in the same manner as the publication. Microencapsulation is a so-called coacervation method utilizing insolubilization of a polymer material, a so-called interfacial polymerization microencapsulation method in which a capsule film is formed by polymerizing at the interface of dispersed particles, in
Situ microencapsulation polymerization method, submerged drying method, submerged curing coating microencapsulation method, spray drying microencapsulation method that forms a capsule film on the surface by spraying droplets in gas can do. Details of these technologies are described in books such as "Kondo Yasushi, New Edition Microcapsules: Manufacturing Method, Properties, and Applications Sankyo Publishing". By encapsulating and dispersing in another resin, the range of application can be expanded.

Next, an optical element (optical element of the present invention) using the polymer gel composition of the present invention will be described. When the polymer gel composition of the present invention solidified as described above is used, the optical element of the present invention can be used as it is as an optical element for light control, display, etc. Further, in order to improve strength, durability and function, the polymer gel composition of the present invention may be formed into a layer on another substrate, or the polymer gel composition of the present invention may be formed between a pair of substrates. It is also possible to form an optical element by sandwiching the layers.

When the optical element of the present invention is used for a display element, a recording element, an optical modulator, etc., it is provided with an electric field applying means, but it is used for an optical shutter which responds to an electric field, a sensor, etc. In that case, there is no need to provide an electric field applying means. As a general electric field applying means, a pair of electrodes or the like can be used, and it is also preferable to perform patterning or segmentation of these electrodes to dimming an arbitrary part. It is also preferable to dispose a chargeable polymer gel having specific characteristics corresponding to these patterns.

In the optical element of the present invention, the chargeable polymer gel is preferably immobilized on the electrode so that it can reversibly swell and contract due to the interaction with the electrode. Further, when there are a plurality of electrodes, the immobilization may be performed on all the electrodes.

Immobilization of such a chargeable polymer gel is
It can be carried out by using various bifunctional compounds and adhesives, or by physical means. Specifically, for example, a functional group can be introduced by previously treating the electrode substrate with a reactive silane coupling material, and the functional group of the chargeable polymer gel can be reacted to form a covalent bond. Is. In addition, it is possible to physically fix the chargeable polymer gel by a method of fixing with various polyfunctional compounds or adhesives, or by three-dimensionally processing on the substrate. In the immobilization of the chargeable polymer gel, if the electrode (substrate) is too closely attached, the response characteristics may deteriorate. Therefore, the surface of the substrate etc. should be three-dimensionally processed to make a space, and A means for binding the chargeable polymer gel through a means for binding to the moiety or a long-chain compound is also preferably performed.

In the optical element of the present invention, the arrangement (encapsulation) position of the polymer gel composition, that is, the light control layer is preferably sealed. Since the light control layer is hermetically sealed, the light control layer (polymer gel composition) does not come into contact with the outside air, and deterioration can be prevented. Such a configuration
For example, the dimming layer sandwiched between the electrodes may be resin-sealed, or the dimming layer may be arranged between the cell-shaped electrodes.

Various layers may be formed on the optical element of the present invention. Examples thereof include a protective layer for the purpose of protecting the optical element, an antifouling layer, an ultraviolet absorbing layer, an antistatic layer, a light reflecting layer, a dielectric layer, and a colored layer such as a color filter.

The optical element of the present invention will be described below with reference to the drawings. It should be noted that members having the same function are given the same reference numerals throughout the drawings, and description thereof will be omitted. Figure 1
FIG. 3 is a schematic configuration diagram showing an example of an optical element of the present invention.
The optical element shown in FIG. 1 has a configuration in which the chargeable polymer gel particles 5 and the liquid 4 are enclosed in a space (cell) between a pair of (electrode substrates 1, 2) at least one of which is transparent. . Further, a spacer 3 is provided in order to keep a constant space between the pair of electrode substrates. At this time, the chargeable polymer gel 5 is fixed on the surface of the electrode substrate 1.
The arrow indicates the visual direction.

The electrode substrates 1 and 2 are usually manufactured by forming a current-carrying member on the substrate member. As the substrate member, polyester, polyimide, polymethylmethacrylate, polystyrene, polypropylene, polyethylene, polyamide, nylon, polyvinyl chloride, polyvinylidene chloride, polycarbonate, polyether sulfone, silicone resin, polyacetal resin, fluorine resin, cellulose derivative, A polymer film such as polyolefin, a plate-shaped substrate, an inorganic substrate such as a glass substrate, a metal substrate or a ceramic substrate is preferably used. When used as a transmission type optical element, a substrate member having a light transmittance of at least 50% or more is preferably used.

As the current-carrying member, one having a metal oxide layer typified by tin oxide-indium oxide (ITO), tin oxide, zinc oxide is preferably used. A transparent electrode having a light transmittance of at least 50% or more is preferably used. In addition, in the case of use as a reflection type optical element, the current-carrying member provided on the electrode substrate 2 farther from the visual direction is a metal typified by tin oxide-indium oxide (ITO), tin oxide, zinc oxide, or the like. Besides the oxide layer,
Conductive polymer, carbon, copper, aluminum, gold,
A metal layer represented by silver, nickel, platinum, or the like can be used.

Various thicknesses and sizes of the electrode substrates 1 and 2 can be used depending on a desired optical element (display element), and there is no particular limitation, but the preferable thickness range is 10 μm to 2 μm.
It is 0 nm. When both the electrode substrates 1 and 2 are transparent electrodes, they can be used as a transmissive display element. FIG. 1 shows an example in which the structure enclosed between a pair of substrates is shown. However, as shown in FIG. 2, a plurality of the structures shown in FIG. 1 may be laminated. By stacking layers enclosing chargeable polymer gels (chargeable polymer gels 5a, 5b, 5c) containing pigments (light control materials) of different colors, it can be used for a laminated color display element. It is possible.

Depending on the use of the optical element (display element), the electrode substrates 1 and 2 are for driving wirings, thin film transistors, diodes having a metal / insulating layer / metal structure, variable capacitors, ferroelectrics, etc. A switching element may be formed. Generally, when displaying an image as a display application, it can be realized by energizing a desired pattern and changing the volume of the chargeable polymer gel on the pattern in a structure having a patterned electrode. Further, color display can be realized by immobilizing a plurality of chargeable polymer gels of different colors on each pattern and selectively energizing various patterns.

[0042]

EXAMPLES The present invention will be described more specifically below with reference to examples. However, each of these examples does not limit the present invention.

Example 1 Preparation of Nonionic Polymer Gel Particles Containing Charging Agent Nonionic polymer gel particles swelling / contracting by electric field were prepared by reverse phase suspension polymerization as shown below. . As the main monomer, 10 g of N-isopropylacrylamide,
0.1 g of methylenebisacrylamide was used as a cross-linking agent, and 20 g of distilled water and 0.1 g of ammonium persulfate were added to this.
g, a blue pigment having primary particles of 0.1 μm as a pigment (charging agent) (manufactured by Dainippon Ink and Chemicals, Inc .: microencapsulated pigment,
MC Blue 182-E) 8.0g was added, and the aqueous solution A which mixed with stirring was adjusted. The above work was performed under nitrogen. A solution prepared by dissolving 1.0 g of a sorbitol-based surfactant (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd .: Sorgen 50) in 200 ml of cyclohexane was added to a nitrogen-substituted container, and the aqueous solution A prepared above was added thereto, and a rotary stirring device was added. And was stirred at high speed to emulsify. After emulsification, the temperature of the reaction system was adjusted to 20 ° C., and a 50% aqueous solution of tetramethylethylenediamine was added to the solution while stirring the solution to carry out polymerization. After the polymerization, the produced colored polymer gel was collected and washed with pure water.

Then, the water content in the colored polymer gel was removed by the freeze-drying method. After the distillation, the dimethylformamide (DMF), which had been stored by adding molecular sieves, was added to the colored polymer gel in the dry state to swell the nonionic polymer gel particles (colored polymer gel particles).

-Preparation of light control element-On an electrode substrate with tin oxide having a size of 50 mm x 50 mm,
The colored polymer gel particles prepared above were immobilized by the following method. A silane coupling agent (3-Glycidoxy) was used as a binder layer for fixing the colored polymer gel on the electrode.
It was formed by applying a solution of propyltrimethyoxysilane to the surface of the electrode, reacting it with heating, and then washing.

Next, a solution containing the colored polymer gel particles and DMF prepared above is prepared, and the solution is brought into contact with the electrode surface and heated to separate the reactive silane coupling portion on the glass surface from the gel particles. It was immobilized by a chemical reaction. Further, an electrode substrate with tin oxide having a size of 50 mm × 50 mm is used as a counter substrate, and a resin spacer having a thickness of 500 μm is arranged on the surface so as to face the electrode surface, and the outer peripheral portion except for a part of the solution injection opening is provided with a thermal adhesive. It was sealed with. As a swelling liquid (liquid) of colored polymer gel inside the cell, DMF (volume resistivity 1
0 ⁷ about [Omega] cm) only after the injection and the opening to prepare a sealed light control device (dimmer cell). The swelling liquid (liquid) in the cell was sampled and the volume resistivity was measured.
The volume resistance value derived from F is shown.

-Evaluation-It was found that in the obtained light control device, the volume of the colored polymer gel particles was changed by applying a DC voltage of 35 V between the electrodes facing each other. The colored polymer gel particles swelled when the electrode on which the colored polymer gel particles were immobilized became the cathode, and conversely contracted when the electrode became the anode. As a result, it was found that the colored polymer gel particles swell and contract depending on the electric field. The contrast ratio obtained from the reflectance was 30 or more, and the visibility was excellent. On the other hand, 35V
It was repeated 1 million times by reversing the polarity of the applied voltage, but it was confirmed that no bubbles were generated and it was extremely stable.

Example 2 Preparation of Ionic Polymer Gel Particles Ionic polymer gel particles that swell and contract due to an electric field were prepared as follows. Acrylic acid 1 as a monomer
0 g, methylenebisacrylamide 0.0 as a cross-linking agent
2 g and 25 g of distilled water were dissolved and mixed with 6 g of sodium hydroxide to prepare a monomer aqueous solution in which acrylic acid was neutralized. The monomer aqueous solution was placed in a flask, deaerated and replaced with nitrogen. This monomer mixture, to which 0.2 g of ammonium persulfate was added as a polymerization initiator, was added to 200 ml of cyclohexane as a dispersion medium, and this was added to a nitrogen-purged container, and the mixture was stirred at high speed with a homogenizer to emulsify. Furthermore, 0.1 ml of tetramethylethylenediamine was added as a polymerization accelerator, and polymerization was carried out at 30 ° C. for 5 hours. The particles produced by the polymerization were put into a large amount of distilled water and the operation of filtering the particles was repeated to perform purification. In this way, ionic polymer gel particles were produced.

-Preparation of light control element-On an electrode substrate with tin oxide having a size of 50 mm x 50 mm,
The ionic polymer gel particles produced above were immobilized by the following method. The binder layer for fixing the ionic polymer gel on the electrode is a silane coupling agent (3-Glyci).
doxypropyrimethyoxysilan
e) It was formed by applying the solution to the electrode surface, heating and reacting it, and then washing.

Next, the previously prepared ionic polymer gel particle dispersion and the electrode surface are brought into contact with each other and heated to chemically react and immobilize the gel particles with the reactive silane coupling portion on the glass surface. did. Furthermore, size 50 mm ×
A 50 mm tin oxide electrode substrate was used as a counter substrate, and a resin spacer of 500 μm was arranged on the surface so as to face the electrode surface, and the outer peripheral portion was sealed with a thermal adhesive except for some solution injection openings. After only DMF (volume resistivity of about 10 ⁷ Ωcm) was injected into the cell as a swelling liquid (liquid) of ionic polymer gel particles, the opening was sealed to produce a light control element (light control cell). The swelling liquid (liquid) in the cell was sampled and the volume resistivity was measured. As a result, the volume resistance value derived from DMF was shown.

-Evaluation-It was found that in the obtained light control device, the volume of the ionic polymer gel particles was changed by applying a DC voltage of 35 V between the opposed electrodes. The ionic polymer gel particles swelled when the electrode on which the ionic polymer gel particles were immobilized became the cathode, and conversely contracted when the electrode became the anode. As a result, it was found that the ionic polymer gel particles swell and contract depending on the electric field. On the other hand, although the repetition due to the polarity reversal of the applied voltage of 35 V was carried out 1 million times, it was confirmed that no bubbles were generated and it was extremely stable.

Example 3 Preparation of Ionic Polymer Gel Particles Containing Charging Agent (Colored Acrylic Acid Gel) Ionic polymer gel particles containing carbon black as a black pigment (charging agent) were prepared as follows. Manufactured by various processes. 10 g of carbon black having a primary particle size of about 0.1 μm (Showa Cabot Co., Show Black: abbreviated as CB hereinafter) was mixed with 50 ml of distilled water to which 0.3 g of Emulgen 909 (made by Kao) was added as a surfactant, A CB dispersion solution in which CB was uniformly dispersed was prepared using an ultrasonic dispersion device. Acrylic acid (10 g) as a monomer and methylenebisacrylamide (0.02 g) as a cross-linking agent were dissolved in distilled water (20 ml) and mixed with sodium hydroxide (6 g) to prepare a monomer aqueous solution in which acrylic acid was neutralized.
This aqueous solution was mixed with the previously prepared CB dispersion solution, which was placed in a flask, which was deaerated and replaced with nitrogen. 0.2 g of ammonium persulfate as a polymerization initiator in this monomer mixture
Cyclohexane 200 which is a dispersion medium
The mixture was added to a vessel, added to a vessel purged with nitrogen, and stirred at high speed with a homogenizer to emulsify. Furthermore, 0.1 ml of tetraethylethylenediamine as a polymerization accelerator
Was added and polymerization was carried out at 30 ° C. for 5 hours.

The black polymer gel particles produced by the polymerization were put into a large amount of distilled water and the operation of filtering this was repeated to carry out purification. Then, it was dehydrated with a large amount of methanol and dried. The coarse particles of the obtained polymer gel were classified to prepare a colored acrylic acid gel (black polymer gel particles) having an average particle diameter when dried of 10 μm.

-Preparation of light control element-On a tin oxide electrode substrate having a size of 50 mm x 50 mm,
The black polymer gel particles produced above were immobilized by the following method. A silane coupling agent (3-Glycidoxy) was used as a binder layer for fixing the colored polymer gel on the electrode.
It was formed by applying a solution of propyltrimethyoxysilane on the surface of the electrode, reacting with heating, and then washing.

Next, the solution prepared from the black polymer gel particles and DMF prepared above was prepared, and the solution was brought into contact with the electrode surface and heated to react with the reactive silane coupling part on the glass surface and the gel. The particles were chemically reacted and immobilized. Further, an electrode substrate with tin oxide having a size of 50 mm × 50 mm is used as a counter substrate, and a resin spacer having a thickness of 500 μm is arranged on the surface so as to face the electrode surface, and the outer peripheral portion except for a part of the solution injection opening is provided with a thermal adhesive. It was sealed with. DMF as swelling liquid (liquid) of ionic polymer gel particles inside the cell
After injecting only (volume resistivity of about 10 ⁷ Ωcm), the opening was sealed to prepare a light control element (light control cell). The swelling liquid (liquid) in the cell was sampled and the volume resistivity was measured. As a result, the volume resistance value derived from DMF was shown.

-Evaluation-It was found that in the obtained light control element, the volume of the ionic polymer gel particles was changed by applying a DC voltage of 35 V between the opposed electrodes. The ionic polymer gel particles swelled when the electrode on which the ionic polymer gel particles were immobilized became the cathode, and conversely contracted when the electrode became the anode. As a result, it was found that the ionic polymer gel particles swell and contract depending on the electric field. The contrast ratio obtained from the reflectance was 30 or more, and the visibility was excellent.
On the other hand, repeat 1 by reversing the polarity of the applied voltage of 35V.
It was carried out, 000,000 times, but it was confirmed that no bubbles were generated and it was extremely stable.

Comparative Example 1 Preparation of Colored Acrylic Acid Gel Particles of pH responsive polymer gel containing carbon black as a black pigment (gel particles similar to those in Example 3) were produced by the following process. did. Primary particle size about 0.1μ
Distilled water 5 to which 0.3 g of Emulgen 909 (manufactured by Kao) was added as a surfactant 10 g of m carbon black (Showa Cabot, Show Black: abbreviated as CB hereinafter)
0 ml was mixed and a CB dispersion solution was prepared in which CB was uniformly dispersed using an ultrasonic dispersion device. Acrylic acid (10 g) as a monomer and methylenebisacrylamide (0.02 g) as a cross-linking agent were dissolved in distilled water (20 ml) and mixed with sodium hydroxide (6 g) to prepare a monomer aqueous solution in which acrylic acid was neutralized. This aqueous solution was mixed with the previously prepared CB dispersion solution, which was placed in a flask, which was deaerated and replaced with nitrogen. This monomer mixture, to which 0.2 g of ammonium persulfate was added as a polymerization initiator, was added to 200 ml of cyclohexane as a dispersion medium, and this was added to a nitrogen-purged container, and the mixture was stirred at high speed with a homogenizer to emulsify. Furthermore, 0.1 ml of tetraethylethylenediamine was added as a polymerization accelerator, and polymerization was carried out at 30 ° C. for 5 hours.

The black polymer gel particles produced by the polymerization were put into a large amount of distilled water, and the operation of filtering the particles was repeated to carry out purification. Then, it was dehydrated with a large amount of methanol and dried. The coarse particles of the obtained polymer gel were classified to prepare a colored acrylic acid gel (black polymer gel particles) having an average particle diameter when dried of 10 μm.

—Preparation of Light Control Device— The black polymer gel particles prepared above were immobilized on the electrode substrate with tin oxide having a size of 100 mm × 100 mm by the following method. The binder layer for fixing the polymer gel on the electrode is covered with a silane coupling agent (3-Glycidoxy).
It was formed by applying a solution of propyltrimethyoxysilane on the surface of the electrode, reacting with heating, and then washing. Next, a solution containing the black polymer gel particles and water prepared above is prepared, and the reactive silane coupling part on the glass surface and the gel particles are chemically reacted by bringing this into contact with the electrode surface and heating. Fixed. further,
An electrode substrate with tin oxide having a size of 100 mm × 100 mm was used as a counter substrate, and a resin spacer having a thickness of 50 μm was dispersed on this surface, and then an ultraviolet curable resin was applied to the outer peripheral portion except a part of the openings, and the above gel particles were applied. The fixed substrate was laminated and irradiated with ultraviolet rays for adhesion. Next, a 0.1N potassium hydroxide aqueous solution as a swelling liquid of the polymer gel was injected into the cell by a vacuum encapsulation method, and then the opening was sealed to prepare a light control element (light control cell). The electrode side on which the black polymer gel particles were fixed was used as an anode, and wiring was performed from the power source to the electrode so that a direct current of 5 V could be passed. The swelling liquid in the cell was sampled and the volume resistivity was measured.
It was ^-2 Ωcm.

—Evaluation— In the obtained light control element before energization, since the black polymer gel particles are in a swollen state, incident light is absorbed and the amount of transmitted light is about 2
%Met. When electricity was applied, the ion concentration on the surface of the electrode changed and the black polymer gel particles contracted to transmit light, and the amount of transmitted light increased, but it was confirmed that a large amount of bubbles were generated. When the power was turned off again, the amount of transmitted light returned to the original value instantly. When energization was repeated several tens of times, liquid leakage occurred from the sealed portion due to the generated bubbles.

[0061]

As described above, according to the present invention, it is possible to obtain a large amount of change in light scattering rate, reflectance, absorption amount of light, etc. according to an electric field, and to have stable repeatability. ,
It is possible to provide a polymer gel composition which has a simple structure and can be applied to a transmissive display element, and an optical element using the same.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an example of an optical element of the present invention.

FIG. 2 is a schematic configuration diagram showing another example of the optical element of the present invention.

[Explanation of symbols]

1, 2 electrode substrate 3 spacers 4 liquid 5 Chargeable polymer gel particles

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Masato Mikami             Fuji Zero, 1600 Takematsu, Minamiashigara City, Kanagawa Prefecture             X Co., Ltd. (72) Inventor Akashi Kazuro             Fuji Zero, 1600 Takematsu, Minamiashigara City, Kanagawa Prefecture             X Co., Ltd. F-term (reference) 2H042 BA02 BA11 BA16                 4J002 BG011 BG041 BG131 BH021                       BQ001 DA116 EG076 EJ066                       EN096 EP016 EU026 FD097                       FD106 FD207 GP00 HA05

Claims (12)

[Claims] 1. A liquid and the liquid absorbing and absorbing the liquid in response to an electric field.
A polymer gel composition comprising: a chargeable polymer gel that changes in volume by being released. 2. The polymer gel composition according to claim 1, wherein the liquid is an insulating liquid. 3. The volume resistivity of the liquid is 10 ³ Ωcm.
It is above, The polymeric gel composition of Claim 1 or 2 characterized by the above-mentioned. 4. The polymer gel composition according to claim 1, wherein the chargeable polymer gel is an ionic polymer gel. 5. The chargeable polymer gel is an ionic polymer gel containing a charging agent.
3. The polymer gel composition according to any one of 3 above. 6. The chargeable polymer gel is a nonionic polymer gel containing a charging agent.
4. The polymer gel composition according to any one of 3 to 3. 7. The polymer gel composition according to claim 1, wherein the chargeable polymer gel contains a light control material. 8. The polymer gel composition according to claim 5, wherein the charging agent is a light control material. 9. The polymer gel composition according to claim 1, wherein the chargeable polymer gel has a spherical shape. 10. An optical element comprising the polymer gel composition according to claim 1. 11. The optical element according to claim 10, further comprising an electric field applying means for applying an electric field to the polymer gel composition. 12. The optical element according to claim 10, further comprising an electrode for applying an electric field to the polymer gel composition, wherein the chargeable polymer gel is immobilized on the electrode.