JP2018049219A - Electromagnetic wave adjustment material and electromagnetic wave adjustment element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electromagnetic wave adjustment material that makes it possible to prepare an electromagnetic wave adjustment element having excellent responsiveness in a wide temperature range, and an electromagnetic wave adjustment element prepared with the electromagnetic wave adjustment material.SOLUTION: An electromagnetic wave adjustment element contains a first medium 11 that can be cured by energy ray irradiation, second media 9 that contain silicone and are dispersed in the first medium 11, and electromagnetic wave adjustment particles 10 dispersed in the second media 9.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electromagnetic wave adjusting material and an electromagnetic wave adjusting element.

  From the viewpoints of energy saving, privacy protection, anti-glare and the like, there is an increasing interest in electromagnetic wave adjusting elements that can electrically control the transmittance or scattering intensity of electromagnetic waves such as visible light and near infrared rays. Up to now, as electromagnetic wave adjusting elements, those using electrochromic materials, liquid crystals, particle dispersions, and the like as electromagnetic wave adjusting methods have been put into practical use. Among these, the type using the electrochromic phenomenon has a problem that it is difficult to increase the area. Further, the type using liquid crystal switches between a light transmission state and a light scattering state, and there is a problem that it cannot be in a light shielding state.

  On the other hand, the type using a particle dispersion liquid controls the electromagnetic wave transmittance by switching between the non-oriented (dispersed) state of particles and the oriented state or aligned state by applying a voltage. Therefore, the application to windows of automobiles, airplanes, buildings, etc. is progressing. In the electromagnetic wave adjusting element of the type using the particle dispersion liquid, the transmission of the electromagnetic wave is controlled by applying a voltage to the particles having the property that the electromagnetic wave transmittance is different between the dispersed state and the aligned state or the aligned state. Control the rate. For example, Patent Document 1 discloses a method for switching between a non-oriented state (colored state) and an oriented state (transparent state) of particles by applying voltage to a dispersion of needle-like particles containing iodine in a polymer medium. Have been described.

JP 2002-189123 A

  In the method described in Patent Document 1, when the electromagnetic wave adjusting element is placed in a low temperature environment (for example, 0 ° C. or less), the rate of change from the colored state to the transparent state when a voltage is applied, and the voltage application There is a problem that the speed of change from the transparent state to the colored state is slow, that is, the speed of change (response speed) between the transparent state and the colored state due to ON / OFF of the voltage is slow.

  In view of the above problems, an object of the present invention is to provide an electromagnetic wave adjusting material capable of producing an electromagnetic wave adjusting element having excellent responsiveness in a wide temperature range, and an electromagnetic wave adjusting element using the same.

Specific means for solving the above problems include the following embodiments.
<1> a first medium curable by energy ray irradiation, a second medium containing silicone and dispersed in the first medium, and electromagnetic wave adjusting particles dispersed in the second medium, An electromagnetic wave adjusting material including
<2> The electromagnetic wave adjusting material according to <1>, wherein the first medium includes a compound having a (meth) acryloyl group.
<3> The electromagnetic wave adjusting material according to <1> or <2>, wherein the silicone includes a silicone having a substituent other than a methyl group or a hydrogen atom bonded to a silicon atom.
<4> The electromagnetic wave adjusting material according to any one of <1> to <3>, wherein the second medium has a viscosity at 25 ° C. of 100 mPa · s to 3,000 mPa · s.
<5> The electromagnetic wave adjustment according to any one of <1> to <4>, wherein the second medium has an Andrade equation coefficient E / R of 9.0 × 10 ⁷ or less regarding temperature and viscosity. material.
<6> The electromagnetic wave adjusting material according to any one of <1> to <5>, wherein the nonvolatile content of the second medium is 95% by mass or more.
<7> The electromagnetic wave adjusting material according to any one of <1> to <6>, having an interface layer between the first medium and the second medium.
<8> A pair of conductive substrates, and an electromagnetic wave adjustment layer formed from the electromagnetic wave adjustment material according to any one of <1> to <7> disposed between the pair of conductive substrates. And an electromagnetic wave adjusting element.
<9> a pair of conductive base materials and an electromagnetic wave adjustment layer disposed between the pair of conductive base materials, wherein the electromagnetic wave preparation layer is a cured first medium, silicone An electromagnetic wave adjusting element comprising: a second medium that is dispersed in the first medium; and electromagnetic wave adjusting particles that are dispersed in the second medium.
<10> an electromagnetic wave including a cured first medium, a second medium containing silicone and dispersed in the first medium, and electromagnetic wave adjusting particles dispersed in the second medium An electromagnetic wave adjustment element having an adjustment layer.

  ADVANTAGE OF THE INVENTION According to this invention, the electromagnetic wave adjustment material which can produce the electromagnetic wave adjustment element excellent in the responsiveness in a wide temperature range, and the electromagnetic wave adjustment element using the same are provided.

It is a schematic sectional drawing of an electromagnetic wave adjustment element. It is a schematic sectional drawing which shows a state when electromagnetic waves inject into the electromagnetic wave adjustment element to which the voltage is not applied. It is a schematic sectional drawing which shows a state when electromagnetic waves inject into the electromagnetic wave adjustment element to which the voltage is applied.

Hereinafter, embodiments for carrying out the present invention will be described in detail. However, the present invention is not limited to the following embodiments. In the following embodiments, the constituent elements (including element steps and the like) are not essential unless explicitly specified, unless otherwise clearly considered essential in principle. The same applies to numerical values and ranges thereof, and the present invention is not limited thereto.
In this specification, the term “process” includes a process that is independent of other processes and includes the process if the purpose of the process is achieved even if it cannot be clearly distinguished from the other processes. It is.
In the present specification, the numerical ranges indicated by using “to” include numerical values described before and after “to” as the minimum value and the maximum value, respectively.
In the numerical ranges described stepwise in this specification, the upper limit value or the lower limit value described in one numerical range may be replaced with the upper limit value or the lower limit value of another numerical range. Good. Further, in the numerical ranges described in this specification, the upper limit value or the lower limit value of the numerical range may be replaced with the values shown in the examples.
In the present specification, the content rate or content of each component in the composition is such that when there are a plurality of substances corresponding to each component in the composition, the plurality of kinds present in the composition unless otherwise specified. It means the total content or content of substances.
In the present specification, the particle diameter of each component in the composition is a mixture of the plurality of types of particles present in the composition unless there is a specific indication when there are a plurality of types of particles corresponding to each component in the composition. Means the value of.
In this specification, the term “layer” or “film” refers to a part of the region in addition to the case where the layer or the film is formed when the region where the layer or film exists is observed. It is also included when it is formed only.
In this specification, the term “lamination” indicates that layers are stacked, and two or more layers may be combined, or two or more layers may be detachable.
In the present specification, “(meth) acryloyl group” means at least one of acryloyl group and methacryloyl group, “(meth) acryl” means at least one of acryl and methacryl, “(meth) acrylate” means acrylate and It means at least one of methacrylate.

<Electromagnetic wave adjusting material>
The electromagnetic wave adjusting material of the present embodiment includes a first medium curable by energy ray irradiation, a second medium containing silicone and dispersed in the first medium, and dispersed in the second medium. And electromagnetic wave adjusting particles.

  The electromagnetic wave adjusting material of the present embodiment is such that the second medium in which the electromagnetic wave adjusting particles are dispersed is further dispersed in the first medium, so that the dispersed state of the electromagnetic wave adjusting particles in the electromagnetic wave adjusting layer is the first. Stable by curing of one medium. Thereby, the display nonuniformity of an electromagnetic wave adjustment element is suppressed effectively.

  Furthermore, as a result of studies by the present inventors, it has been found that an electromagnetic wave adjusting element manufactured using an electromagnetic wave adjusting material having the above-described configuration is excellent in responsiveness in a low temperature environment. The reason for this is not clear, but the silicone contained in the second medium dispersed in the first medium has a low temperature dependence of viscosity, and the increase in viscosity is suppressed even in a low temperature environment. This is presumably because the decrease in the switching speed between the non-oriented state and the oriented state of the electromagnetic wave adjusting particles dispersed in the second medium is suppressed.

(First medium)
The first medium is not particularly limited as long as it can be cured by energy ray irradiation and can disperse the second medium (phase-separate from the second medium). Energy rays are not particularly limited, and examples include ultraviolet rays, visible rays, and electron beams. From the viewpoints that curing can be performed in a short time, deterioration due to heat is low due to low temperature treatment, and there are few restrictions on the coating process, ultraviolet rays are preferable.

  From the viewpoint of versatility and transparency, the first medium preferably includes a compound that is polymerized by energy beam irradiation, and more preferably includes a compound having a (meth) acryloyl group as a compound that is polymerized by energy beam irradiation. preferable. The compound having a (meth) acryloyl group may be a low molecular compound such as a monomer or an oligomer, or a high molecular compound.

  Examples of the low molecular weight compound having a (meth) acryloyl group include (meth) acrylate, ether (meth) acrylate, urethane (meth) acrylate, and the like from the viewpoint of flexibility after curing of the first medium (meta ) At least one selected from the group consisting of acrylate, ether (meth) acrylate and urethane (meth) acrylate is preferred.

  Examples of the polymer compound having a (meth) acryloyl group include poly (meth) acrylic resins, polyvinyl alcohol resins, polyethylene resins, polypropylene resins, polyurethane resins, polyester resins, and the like. From the viewpoint of flexibility after curing, at least one selected from the group consisting of poly (meth) acrylic resins, polyurethane resins and polyether resins is preferred.

  From the viewpoint of durability, the compound having a (meth) acryloyl group preferably has at least one selected from the group consisting of an alkyl group having 1 to 16 carbon atoms and an aryl group having 6 to 10 carbon atoms. Examples of the alkyl group having 1 to 16 carbon atoms include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, amyl group, isoamyl group, hexyl group, and cyclohexyl group. Examples of the aryl group having 6 to 10 carbon atoms include a phenyl group and a naphthyl group.

  The viscosity of the first medium is not particularly limited and can be appropriately selected according to the purpose. From the viewpoint of workability of production of the electromagnetic wave adjusting material, the viscosity of the first medium is preferably 100 mPa · s to 65,000 mPa · s at 25 ° C., and 1,000 mPa · s to 60,000 mPa · s. s is more preferable, and 5,000 mPa · s to 55,000 mPa · s is even more preferable.

  In this specification, the viscosity at 25 ° C. of the first medium is a value measured by an E-type viscometer (RE85U, Toki Sangyo Co., Ltd.).

  The refractive index of the first medium is not particularly limited. When the electromagnetic wave adjusting element is used as a dimming element that controls the transmission of visible light, from the viewpoint of transparency when no voltage is applied, the refractive index of the cured first medium and the second The smaller the difference from the refractive index of the medium, the better. Specifically, the difference between the refractive index of the first medium in the cured state and the refractive index of the second medium is preferably 0.005 or less, more preferably 0.004 or less, More preferably, it is 0.002 or less.

  In this specification, the refractive index of the cured first medium is a value measured by an Abbe refractometer (for example, DR-A1, Atago Co., Ltd.), and the refractive index of the second medium is a digital refractometer ( For example, the value is measured by RX-5000α, Atago Co., Ltd.). Each measurement is carried out three times at 25 ° C., and the average of the three times is taken as the refractive index of each.

  The first medium may contain a polymerization initiator in addition to the compound that can be cured by irradiation with energy rays. The kind in particular of polymerization initiator is not restrict | limited, It can select according to the kind of compound which can be hardened | cured by energy ray irradiation. Only one polymerization initiator or two or more polymerization initiators may be used.

  The first medium may contain additives for adjusting the refractive index or viscosity of the first medium, preventing coloration, etc., as necessary, in addition to the compound curable by irradiation with energy rays and the polymerization initiator. Good.

(Second medium)
The second medium is not particularly limited as long as it contains silicone and can be dispersed in the first medium (phase-separated from the first medium). Only one type of silicone or two or more types of silicones may be used.

  From the viewpoint of good driveability of the electromagnetic wave adjusting particles, the weight average molecular weight of the silicone is preferably 50,000 or less, more preferably 45,000 or less, and further preferably 40,000 or less. .

  From the viewpoint of good orientation of the electromagnetic wave adjusting particles with a voltage applied, the weight average molecular weight of the silicone is preferably 1,000 or more, more preferably 1,500 or more, and 2,000. It is still more preferable that it is above.

  The weight average molecular weight of silicone is a value measured by gel permeation chromatography under the following conditions.

(conditions)
Sample concentration: 10 mg / mL
Injection volume: 50 μL
Detector: Hitachi, Ltd., RI-monitor, trade name “L-3300RI”
Pump: Hitachi, Ltd., trade name “L-6000”
Column: Hitachi Chemical Co., Ltd., trade names “GL-R420”, “GL-R430” and “GL-R440” are used together. Eluent: Tetrahydrofuran (THF), but toluene is used for dimethyl silicone Measurement temperature: 23 ° C
Flow rate: 1.75 mL / min Calibration curve: polystyrene

  Examples of the silicone include dimethyl silicone, methyl hydrogen silicone, methyl phenyl silicone, dimethyl diphenyl silicone, aralkyl modified silicone, alkyl / aralkyl modified silicone, long chain alkyl modified silicone, fluoroalkyl modified silicone, and the like. It is preferable that silicone does not have a (meth) acryloyl group.

  The viscosity of the second medium is not particularly limited. For example, the viscosity of the second medium is preferably 100 mPa · s to 3,000 mPa · s at 25 ° C., more preferably 100 mPa · s to 2,500 mPa · s, and 100 mPa · s to 2,000 mPa · s. -More preferably, it is s.

If the viscosity of the second medium is 100 mPa · s or more at 25 ° C., the orientation of the electromagnetic wave adjusting particles tends to be maintained well in a state where a voltage is applied, and if it is 3,000 mPa · s or less, The electromagnetic wave adjusting particles tend to be driven well in a state where a voltage is applied. The viscosity of the second medium can be adjusted by the molecular structure, molecular weight, etc. of the silicone contained in the second medium.
In the present specification, the viscosity of the second medium at 25 ° C. is a value measured by a rheometer (MCR302, Anton Paar Co., Ltd.).

From the viewpoint of reducing the difference in response speed in a wider temperature range in the electromagnetic wave adjusting element, the second medium is an Andrade equation (related to temperature and viscosity shown below) in the temperature range of −20 ° C. to 25 ° C. The value of the coefficient E / R of 1) is preferably 9.0 × 10 ⁷ or less, more preferably 8.5 × 10 ⁷ or less, and even more preferably 8.0 × 10 ⁷ or less. .

η: Viscosity A: Constant E: Flow activation energy R: Gas constant T: Absolute temperature [K]

  In this specification, the viscosity of the second medium is a value measured by a rheometer (MCR302, Anton Paar Co., Ltd.).

  The refractive index of the second medium is not particularly limited. When the electromagnetic wave adjusting element is used as a dimming element for controlling the transmission of visible light, from the viewpoint of transparency in a state where no voltage is applied, the first after the compound curable by energy ray irradiation is cured. The smaller the difference between the refractive index of the medium and the refractive index of the second medium, the better. Specifically, it is preferable that the difference between the refractive index of the first medium after the compound curable by energy ray irradiation is cured and the refractive index of the second medium is 0.005 or less. It is more preferably 004 or less, and further preferably 0.002 or less. The refractive index of the second medium is preferably in the range of 1.420 to 1.590 considering the difference from the refractive index of the first medium.

  As a technique for reducing the refractive index difference between the second medium and the first medium, a silicone having a substituent other than a methyl group or a hydrogen atom bonded to a silicon atom (hereinafter also referred to as a specific silicone) is used. Use. The specific silicone can be adjusted in refractive index according to the type of substituent, the number of substituents, etc., so that it is possible to design or select a specific silicone having a desired refractive index according to the refractive index of the first medium. it can. In particular, when the first medium contains a compound having a (meth) acryloyl group, the refractive index of both can be reduced by using a specific silicone, which is suitable for obtaining a light control device having excellent transparency. The specific silicone may be one type or two or more types.

  In the present specification, the specific silicone means a silicone having a structure in which a substituent other than a methyl group or a hydrogen atom is bonded to a silicon atom of a polysiloxane chain that is a main chain of the silicone. Only one type or two or more types of substituents other than the methyl group or hydrogen atom of the specific silicone may be used.

  The type of the substituent is not particularly limited, and includes an amino group, an epoxy group, an alicyclic epoxy group, a hydroxy group, a mercapto group, an alkyl group having 2 or more carbon atoms, a carboxy group, a polyether group, an aralkyl group, a phenyl group, and the like. Examples thereof include an aryl group, a fluoroalkyl group, a higher fatty acid ester group, and a higher fatty acid amide group.

  Among the substituents, at least one selected from the group consisting of an alkyl group having 2 or more carbon atoms, an aralkyl group, and an aryl group is preferable, an alkyl group having 2 to 6 carbon atoms, an aralkyl group having 7 to 9 carbon atoms, and phenyl. More preferred is at least one selected from the group consisting of groups.

  The structure of the specific silicone is not particularly limited. The structure having the above-described substituents on the side chain of the polysiloxane chain that is the main chain (side chain type), and the above-described substituents on both ends of the polysiloxane chain that is the main chain. Structure (both ends type), structure having the above-described substituent only at one end of the polysiloxane chain that is the main chain (single end type), and both the side chain and both ends of the polysiloxane chain that is the main chain And a structure having a substituted group (side chain terminal type) and the like.

  The second medium is not particularly limited as long as the electromagnetic wave adjusting particles can be dispersed, but is preferably composed of a poor solvent for the electromagnetic wave adjusting particles. From the viewpoint of water resistance of the electromagnetic wave adjusting particles, the moisture content at 25 ° C. is preferably 0.5% by mass or less.

  From the viewpoint of long-term stability of the electromagnetic wave adjusting element, the second medium preferably has a nonvolatile content of 95.00% by mass or more, more preferably 97.00% by mass or more, and 99.99% by mass. More preferably, it is 00 mass% or more. In this specification, the ratio of the non-volatile content means the ratio (percentage) of the mass after allowing the second medium to stand at 120 ° C. for 1 hour under normal pressure with respect to the mass before standing.

  The second medium may contain a particle dispersant for improving the dispersibility of the electromagnetic wave adjusting particles. The particle dispersant may be only one type or two or more types.

  The particle dispersant is preferably a compound having a functional group capable of interacting with the surface of the electromagnetic wave adjusting particle and a siloxane bond from the viewpoint of dispersion stability of the electromagnetic wave adjusting particle. Specifically, a copolymer having a structural unit having at least one kind of functional group capable of interacting with the surface of the electromagnetic wave adjusting particle and a structural unit containing a siloxane bond can be preferably exemplified. The functional group capable of interacting with the surface of the electromagnetic wave adjusting particles can be selected according to the type of the electromagnetic wave adjusting particles.

  When the particle dispersant is a compound having a structural unit containing a siloxane bond, a substituent other than a methyl group or a hydrogen atom may be bonded to the silicon atom of the siloxane bond. The type of the substituent is not particularly limited, and is an amino group, epoxy group, alicyclic epoxy group, hydroxy group, mercapto group, alkyl group having 2 or more carbon atoms, carboxy group, polyether group, aralkyl group, aryl group, fluoro group. Examples thereof include an alkyl group, a higher fatty acid ester group, and a higher fatty acid amide group. The molecular weight of the particle dispersant is preferably close to the molecular weight of the silicone contained in the second medium from the viewpoint of compatibility with the second medium.

  When the second medium includes a particle dispersant, the content is preferably 0.01% by mass to 45% by mass of the second medium, and preferably 0.03% by mass to 40% by mass. More preferred. When the content of the particle dispersant is 0.01% by mass or more of the second medium, the dispersion state of the electromagnetic wave adjusting particles tends to be more stable, and when the content is 45% by mass or less, it acts on the electromagnetic wave adjusting particles. The ratio of the particle dispersant present in a free state in the dispersion medium tends to be small.

  The second medium may contain additives for adjusting the refractive index of the second medium, adjusting the viscosity, preventing coloring, and the like, as necessary, in addition to the silicone and the particle dispersant.

(Electromagnetic wave adjusting particles)
The electromagnetic wave adjusting particles are not particularly limited as long as they can be dispersed in the second medium and their dispersion state can be changed by application of voltage. Examples of such electromagnetic wave adjusting particles include electromagnetic wave adjusting particles having shape anisotropy. Only one type of electromagnetic wave adjusting particles may be used, or two or more types having different shapes, sizes, materials, and the like may be used.

In this specification, “electromagnetic wave adjusting particles having shape anisotropy” means electromagnetic wave adjusting particles having an aspect ratio (short axis / long axis) of ½ or less. The aspect ratio of the electromagnetic wave adjusting particles can be calculated from, for example, the lengths of the long axis and the short axis of the electromagnetic wave adjusting particles measured when observed using a transmission electron microscope or the like.
In this case, the long axis of the electromagnetic wave adjusting particles and the length thereof are the longest distance between two points (point A and point B) on the contour line of the captured image when the captured image of the electromagnetic wave adjusting particles is observed. The length of the line segment between point A and point B and the length thereof.

  The short axis and the length of the electromagnetic wave adjusting particle are a line segment that is perpendicular to the long axis of the electromagnetic wave adjusting particle and connects two points on the contour line of the photographed image (if the length of the line segment is not constant, the length) Is the maximum line segment) and its length.

  From the viewpoint of the responsiveness of the electromagnetic wave adjusting particles when the application of voltage to the electromagnetic wave adjusting element is stopped (change from the aligned state to the non-oriented state), 100 arbitrarily selected by observation with a transmission electron microscope The average aspect ratio of the electromagnetic wave adjusting particles is preferably 1/2 or less, and more preferably 1/10 to 1/2.

  The size of the electromagnetic wave adjusting particles is not particularly limited. From the viewpoint of suppressing the haze of the electromagnetic wave adjusting element, the electromagnetic wave adjusting particles are preferably as small as possible. For example, the length of the long axis is preferably 20 μm or less. From the viewpoint of sufficiently shielding electromagnetic waves in a state where no voltage is applied, the larger the electromagnetic wave adjusting particles, the more preferable. For example, the length of the major axis is preferably 20 nm or more.

  The material of the electromagnetic wave adjusting particles is not particularly limited. Specific examples include iodine, metals, metal oxides, organic pigments, inorganic pigments, etc., and may be selected in consideration of heat resistance, light resistance, water resistance, moisture resistance, etc. according to the use of the electromagnetic wave adjusting element. preferable.

  The content of the electromagnetic wave adjusting particles dispersed in the second medium is preferably 0.1% by mass to 30% by mass of the electromagnetic wave adjusting particle dispersion (the total of the second medium and the electromagnetic wave adjusting particles), More preferably, it is 0.2 mass%-25 mass%, and it is still more preferable that it is 0.3 mass%-20 mass%. When the content of the electromagnetic wave adjusting particles is 0.1% by mass or more of the electromagnetic wave adjusting particle dispersion, the electromagnetic waves tend to be sufficiently shielded in a state where no voltage is applied, and when the content is 30% by mass or less. There is a tendency that electromagnetic waves are sufficiently transmitted while voltage is applied.

  The content of the electromagnetic wave adjusting particle dispersion in the electromagnetic wave adjusting material is preferably 1% by mass to 45% by mass, more preferably 2% by mass to 40% by mass, and more preferably 3% by mass to 3% by mass. More preferably, it is 35 mass%. When the content of the electromagnetic wave adjusting particle dispersion is 1% by mass or more of the electromagnetic wave adjusting material, the electromagnetic wave tends to be sufficiently shielded in a state where no voltage is applied to the electromagnetic wave adjusting element, and is 45% by mass or less. Then, the electromagnetic wave adjusting particle dispersion liquid tends to be dispersed in the state of fine droplets in the first medium.

(Interface layer)
The electromagnetic wave adjusting material may have an interface layer between the first medium and the second medium dispersed in the first medium. If an interface layer exists between the first medium and the second medium, the droplets of the second medium dispersed in the first medium tend to be suppressed from being coalesced. is there. As a result, the uneven distribution of the electromagnetic wave adjusting particles in the electromagnetic wave adjusting layer is suppressed, and variations in the color tone of the electromagnetic wave adjusting element in a state where no voltage is applied tend to be suppressed.

  The interface layer is formed of a polymer compound as a capsule for confining the second medium, for example, even though it is formed of a surfactant so as to cover the surface of the second medium dispersed in the first medium. May be.

  When the interface layer is formed from a surfactant, the type of the surfactant is not particularly limited. For example, a copolymer containing a structural unit having a high affinity with a first medium and a structural unit having a high affinity with a second medium can be mentioned. The copolymer may be any of a random copolymer, a block copolymer, and a graft copolymer.

  Examples of the structural unit having high affinity with the first medium include those corresponding to the structural unit constituting the compound that can be cured by irradiation with energy rays contained in the first medium. For example, it can be selected from structural units constituting an acrylic resin, a vinyl alcohol resin, an ethylene resin, an ether resin, a urethane resin, and an ester resin according to the type of the compound that can be cured by energy ray irradiation.

  The structural unit having a high affinity with the second medium includes a structural unit containing a siloxane bond.

  When the interface layer is formed from a polymer compound, the polymer compound may have a high affinity with the first medium and the second medium, or may have a low affinity. From the viewpoint of the transparency of the electromagnetic wave adjusting material, the polymer compound is preferably highly transparent. In order to enhance the dispersibility of the second medium in the first medium, the interface layer (capsule) formed from the polymer compound may be modified with a polymer chain on the surface in contact with the first medium. . The structure of the polymer chain is not particularly limited. For example, a structure in which one end is chemically or physically adsorbed on the surface of an interface layer (capsule) formed of a polymer, and the other end has a high affinity with the first medium. You may have a unit.

<Electromagnetic wave adjusting element (1)>
The electromagnetic wave adjusting element of the present embodiment has a pair of conductive substrates and an electromagnetic wave adjusting layer formed from the electromagnetic wave adjusting material of the above-described embodiment disposed between the pair of conductive substrates. Alternatively, it has a pair of conductive substrates and an electromagnetic wave adjustment layer disposed between the pair of conductive substrates, the electromagnetic wave adjustment layer comprising a cured first medium and silicone. A second medium dispersed in the first medium, and electromagnetic wave adjusting particles dispersed in the second medium. The electromagnetic wave adjusting element may have other members as necessary.

(Conductive substrate)
Even if the whole base material has electroconductivity, only one part may have electroconductivity. For example, you may use as a conductive base material what has a base material which does not have electroconductivity, and a conductive layer arrange | positioned at the at least one surface. The conductive substrate may be transmissive to visible light or non-transmissive (light reflective). When the electromagnetic wave adjusting element is used as a light control element that controls the transmittance of visible light, the conductive substrate is preferably transparent to visible light, and the visible light transmittance of the conductive substrate is 80. % Or more is more preferable. The visible light transmittance of the conductive substrate can be adjusted by the material used for the conductive layer, the thickness of the conductive layer, and the like.

  When the conductive substrate has a conductive layer on at least one of the non-conductive substrates, the non-conductive substrate is not particularly limited as long as the conductive layer can be formed on at least one surface thereof. Depending on the application of the electromagnetic wave adjusting element, it can be selected. For example, the board or film formed from glass, resin, etc. is mentioned. Examples of the resin include polyesters such as polyethylene terephthalate (PET), polyolefins such as polypropylene, polyvinyl chloride, polyacrylate, polyether sulfone, polyarylate, and polycarbonate. Among these, polyethylene terephthalate is preferable because it is excellent in transparency, moldability, adhesion, workability, and the like.

When the electromagnetic wave adjusting element is used as a light control element that controls the transmittance of visible light, the conductive layer is preferably transmissive to visible light. Specific examples of such a conductive layer include metal oxides such as indium tin oxide (ITO), SnO ₂ , and In ₂ O ₃ , conductive resins such as polyacetylene, polypyrrole, polythiophene, and polyaniline, carbon nanotubes, and silver nanowires. And the like.

  When the electromagnetic wave adjusting element is used for an application that reflects visible light like a rear view mirror for automobiles, a thin film of a metal such as aluminum, gold, silver, or the like, which is a reflector, may be used as the conductive layer.

  The thickness of the conductive layer is not particularly limited, and can be selected according to the use of the electromagnetic wave adjusting element. In general, the thickness of the conductive layer is preferably 10 nm to 5,000 nm. The thickness of the conductive layer can be measured using an optical film thickness meter.

  The surface resistance value of the conductive layer is not particularly limited and can be appropriately selected depending on the purpose. In general, the surface resistance value of the conductive layer is preferably 3Ω / □ to 10,000Ω / □. The surface resistance value of the conductive layer is measured at 25 ° C. using a four-probe method. Alternatively, the surface resistance value of the conductive layer is preferably 1,000Ω / □ to 10,000Ω / □ from the viewpoint of electromagnetic wave transmission near gigahertz (GHz). By having electromagnetic wave permeability in the vicinity of gigahertz, it is possible to transmit electromagnetic waves used in mobile phones and the like.

  In the case where the conductive substrate has a conductive layer on at least one of the non-conductive substrates, an insulating layer having a thickness of about several nm to 1 μm is further provided on the conductive layer so as not to disturb the orientation of the electromagnetic wave adjusting particles. You may do it. By having the insulating layer, the occurrence of a short-circuit phenomenon that may occur due to the mixing of foreign substances tends to be suppressed. When the electromagnetic wave adjusting element is used as a light control element that controls the transmittance of visible light, the insulating layer is preferably transmissive to visible light.

The material of the insulating layer is not particularly limited, and may be an inorganic material, an organic material, or a composite of an inorganic material and an organic material. Examples of inorganic substances include oxides such as SiO ₂ and Al ₂ O ₃ , aluminosilicates such as layered silicate minerals, and silicon nitrides. Examples of organic substances include resins such as polyimide resins and acrylic resins. The material of the insulating layer is selected according to the affinity of the insulating layer to the first medium, the second medium, and the conductive substrate, chemical stability, and the use environment conditions such as temperature, humidity, and solar radiation. The

  The conductive base material may have a primer layer in order to improve adhesion with adjacent layers such as an electromagnetic wave adjusting layer. Examples of the primer layer include a layer formed from a resin. When the electromagnetic wave adjusting element is used as a light control element that controls the transmittance of visible light, the primer layer is preferably transmissive to visible light.

(Electromagnetic wave adjustment layer)
The electromagnetic wave adjustment layer is formed from the electromagnetic wave adjustment material of the above-described embodiment. Specifically, it is formed by irradiating the electromagnetic wave adjusting material with energy rays and curing the first medium contained in the electromagnetic wave adjusting material.

  In the electromagnetic wave adjusting layer, the size (average droplet diameter) of the droplets of the electromagnetic wave adjusting particle dispersion dispersed in the cured first medium is not particularly limited. For example, it may be 0.5 μm to 100 μm, preferably 0.5 μm to 20 μm, and more preferably 1 μm to 10 μm. The average droplet diameter of the electromagnetic wave adjusting particle dispersion is the concentration of each component contained in the second medium, the viscosity of the first medium before curing, the viscosity of the second medium, the first medium before curing and the first medium It can be adjusted by the compatibility of the two media.

  The average droplet diameter of the electromagnetic wave adjusting particle dispersion is measured, for example, by taking an image such as a photograph from one surface direction of the electromagnetic wave adjusting element using an optical microscope and measuring the diameter of 100 arbitrarily selected droplets. The average value can be calculated. It is also possible to take a visual field image with an optical microscope into a computer as digital data and calculate it using image processing software.

  The structure of the electromagnetic wave adjusting layer is not particularly limited, and can be selected according to the use of the electromagnetic wave adjusting element. For example, even if the electromagnetic wave adjustment layer is integrally formed in the space between the pair of conductive substrates, the space between the pair of conductive substrates is partitioned by the partition walls, and the electromagnetic wave adjustment is performed for each space partitioned by the partition walls. A layer may be formed. The space between the conductive substrates can be formed, for example, by arranging spacer beads of a desired size between the conductive substrates.

  The thickness of the electromagnetic wave adjusting layer is not particularly limited and can be selected according to the use of the electromagnetic wave adjusting element. In general, the thickness of the electromagnetic wave adjusting layer is preferably 10 μm to 300 μm, more preferably 20 μm to 250 μm, and still more preferably 25 μm to 200 μm. When the thickness of the electromagnetic wave adjustment layer is 10 μm or more, uneven thickness of the electromagnetic wave adjustment layer tends to be suppressed, and when it is 300 μm or less, the driving voltage tends to be reduced.

  The thickness of the electromagnetic wave adjusting layer can be measured by measuring the thickness including the substrate using a micrometer and subtracting the thickness of the substrate measured in advance. Or it can measure from the cross section obtained by cut | disconnecting an electromagnetic wave adjustment element or an electromagnetic wave adjustment layer.

  The content of the electromagnetic wave adjusting particle dispersion in the electromagnetic wave adjusting layer is preferably 1% by mass to 45% by mass, more preferably 2% by mass to 40% by mass, and more preferably 3% by mass to 35% of the electromagnetic wave adjusting layer. More preferably, it is mass%. When the content of the electromagnetic wave adjusting particle dispersion is 1% by mass or more of the electromagnetic wave adjusting layer, the electromagnetic wave tends to be sufficiently shielded in a state where no voltage is applied to the electromagnetic wave adjusting element, and is 45% by mass or less. Then, the electromagnetic wave adjusting dispersion liquid tends to be dispersed in the form of fine droplets in the cured first medium.

  In order to form an electromagnetic wave adjusting layer in which the electromagnetic wave adjusting particle dispersion is dispersed in the form of droplets, the electromagnetic wave adjusting particle dispersion and the first medium are mixed with a homogenizer, an ultrasonic homogenizer, or the like in the preparation of the electromagnetic wave adjusting material. Method of finely dispersing electromagnetic wave adjusting particle dispersion in one medium, phase separation method by polymerization of resin component in first medium, phase separation method by solvent volatilization, phase separation method by temperature, electromagnetic wave adjusting particle dispersion For example, a method of dispersing in a first medium in a state of being confined in a capsule made of a high molecular polymer can be used.

<Electromagnetic wave adjusting element (2)>
The electromagnetic wave adjustment element of this embodiment has an electromagnetic wave adjustment layer formed from the electromagnetic wave adjustment material of the above-described embodiment. Alternatively, an electromagnetic wave adjustment comprising: a cured first medium; a second medium containing silicone and dispersed in the first medium; and an electromagnetic wave adjusting particle dispersed in the second medium. Having a layer. The electromagnetic wave adjusting element may have other members as necessary.

  The electromagnetic wave adjustment element of this embodiment may be configured such that the electromagnetic wave adjustment layer can be self-supporting without a conductive layer base material. In this case, a conductive layer may be provided on both sides of the electromagnetic wave adjustment layer. The description of the electromagnetic wave adjustment element mentioned above can be referred to for details and preferred embodiments of each member constituting the electromagnetic wave adjustment element.

<Structure of electromagnetic wave adjusting element>
The structure of the electromagnetic wave adjusting element of this embodiment will be described with reference to the drawings. However, the present embodiment is not limited to this. Moreover, the magnitude | size of the member in each figure is notional, The relative relationship of the magnitude | size between members is not limited to this.

  FIG. 1 is a schematic cross-sectional view of an electromagnetic wave adjusting element. The electromagnetic wave adjusting element 3 includes a pair of conductive base materials 4 and an electromagnetic wave adjusting layer 12 disposed therebetween. The conductive substrate 4 includes a substrate 5 and a conductive layer 6, and a primer layer 7 is formed on the conductive layer 6. The electromagnetic wave adjusting layer 12 has a structure in which the second medium 9 is dispersed in the form of droplets in the cured first medium 11 and the electromagnetic wave adjusting particles 10 are dispersed therein.

  A power source 1 is connected to the electromagnetic wave adjusting element 3 via a switch 2. The power source used for operating the electromagnetic wave adjusting element 3 can be, for example, alternating current and a voltage range (effective value) of 5 V to 200 V and a frequency range of 30 Hz to 500 kHz.

  FIG. 2 is a schematic cross-sectional view showing a state when an electromagnetic wave is incident on an electromagnetic wave adjusting element to which no voltage is applied. In a state where the switch 2 of the electromagnetic wave adjusting element 3 is turned off and no voltage is applied, the electromagnetic wave adjusting particles 10 dispersed in the second medium 9 are each directed in a random direction due to Brownian motion ( Non-oriented state). Therefore, the electromagnetic wave 13 incident on the electromagnetic wave adjusting element 3 is absorbed, scattered or reflected by the electromagnetic wave adjusting particles 10 and cannot pass between the electromagnetic wave adjusting particles 10.

  FIG. 3 is a schematic cross-sectional view showing a state when an electromagnetic wave is incident on an electromagnetic wave adjusting element to which a voltage is applied. When a voltage is applied by connecting the switch 2 of the electromagnetic wave adjusting element 3, the electromagnetic wave adjusting particles 10 having an electric dipole moment are arranged along the electric field formed by the applied voltage (alignment state). Therefore, the electromagnetic wave 13 incident on the electromagnetic wave adjusting element 3 passes between the electromagnetic wave adjusting particles 10 without being absorbed, scattered or reflected by the electromagnetic wave adjusting particles 10.

  As described above, the electromagnetic wave permeability of the electromagnetic wave adjusting element can be controlled by switching the orientation state and the non-orientation state of the electromagnetic wave adjusting particles 10 by applying a voltage.

  When the electromagnetic wave adjusting element is used as a dimming element for controlling the transmission of visible light, the color tone of the transmitted visible light can be adjusted by using the electromagnetic wave adjusting particles 10 having a small wavelength dependency of electromagnetic wave absorption in a state where a voltage is applied. It can be brought close to an achromatic color, and a good color balance can be realized.

<Method for producing electromagnetic wave adjusting element>
Hereinafter, an example of the manufacturing method of the electromagnetic wave adjustment element of this embodiment is demonstrated. However, the present embodiment is not limited to this.

  First, an electromagnetic wave adjusting particle dispersion is prepared by mixing the second medium, the electromagnetic wave adjusting particles, and other components included as necessary. Mixing can be performed using a general particle dispersion device such as a homogenizer, ultrasonic wave, bead mill, rocking mill, etc., and either one of these devices can be used or two or more can be used in combination. Good.

  Next, the electromagnetic wave adjusting particle dispersion, the first medium, and other components included as necessary are mixed, and the electromagnetic wave adjusting particle dispersion is dispersed in the form of droplets in the first medium An electromagnetic wave adjusting material is prepared. By adjusting the mixing ratio between the first medium and the electromagnetic wave adjusting particle dispersion, the electromagnetic wave transmittance of the electromagnetic wave adjusting layer can be adjusted.

  Next, the electromagnetic wave adjusting material is applied to a conductive base material (on the case where the conductive base material has a primer layer or the like) to have a desired thickness to form a coating layer. Application of the electromagnetic wave adjusting material can be performed using a general coating means such as a bar coater, an applicator, a doctor blade, a roll coater, a die coater, or a comma coater. When applying the electromagnetic wave adjusting material, the electromagnetic wave adjusting material may be diluted with an appropriate solvent, if necessary. When a solvent is used, it is preferable to remove the solvent by a drying treatment after forming the coating layer. Examples of the solvent include ether solvents such as tetrahydrofuran, hydrocarbon solvents such as toluene, heptane, and cyclohexane, alcohol solvents such as ethanol and methanol, ester solvents such as ethyl acetate, isoamyl acetate, and hexyl acetate.

  After forming the coating layer, or after drying and removing the solvent contained in the coating layer as necessary, the first medium is cured by irradiation with energy rays such as ultraviolet rays. As a result, an electromagnetic wave adjusting layer in which the electromagnetic wave adjusting particle dispersion is dispersed in the form of droplets is formed in the cured first medium.

  An electromagnetic wave adjusting element is obtained by disposing another conductive base material on the electromagnetic wave adjusting layer formed on the conductive base material.

  In the above method, a coating layer is formed on the conductive substrate, and if necessary, the solvent in the coating layer is dried and removed, and then the other conductive substrate is disposed thereon, and then energy is applied. The electromagnetic wave adjusting layer may be formed by irradiating a line. Alternatively, an electromagnetic wave adjusting element may be produced by forming an electromagnetic wave adjusting layer on two conductive substrates and laminating the conductive substrate so that the electromagnetic wave adjusting layers face each other.

  Hereinafter, the present embodiment will be specifically described by way of examples. However, the present embodiment is not limited to these examples.

[Example 1 Viscosity-temperature characteristics of second medium and evaluation of nonvolatile content]
The viscosity at each temperature of the dispersion medium (second medium) shown below was measured using a rheometer (MCR302, Anton Paar Co., Ltd.) in the range of -30 ° C to 150 ° C, and the rate of temperature increase was 5 ° C / min, frequency 1Hz It measured on condition of this.

  From the measurement results obtained, in the range of −20 ° C. to 25 ° C., the horizontal axis represents the reciprocal temperature (1 / T [/ K]), and the vertical axis represents the logarithm of viscosity (ln η [mPa · s]). A graph of Andrade's formula (1) was prepared, and a coefficient (E / R) representing the rate of change in viscosity with respect to temperature was calculated. The results are shown in Table 1.

  Next, 1.0 g of each dispersion medium was weighed in a metal petri dish, allowed to stand at 120 ° C. for 1 hour under normal pressure, then taken out of the dryer, and cooled to room temperature (25 ° C.). It was measured as the mass of the minute, and the ratio (% by mass) of the nonvolatile content relative to the mass before drying was calculated. The results are shown in Table 1.

XF-42-334: Alkyl aralkyl modified silicone (Momentive Performance Materials Japan GK)
・ KF-410: Aralkyl-modified silicone (Shin-Etsu Chemical Co., Ltd.)
・ KF-54: Dimethyldiphenyl silicone (Shin-Etsu Chemical Co., Ltd.)
・ KF-53: Dimethyldiphenyl silicone (Shin-Etsu Chemical Co., Ltd.)
・ SH510: Methyl phenyl silicone (Toray Dow Corning Co., Ltd.)
-KF-96-100cs: dimethyl silicone (Shin-Etsu Chemical Co., Ltd.)
-Dispersion medium X: prepared by the following method

(Preparation of dispersion medium X)
164 g of toluene (reagent special grade, Wako Pure Chemical Industries, Ltd.), 231.4 g of dodecyl methacrylate (Kyoeisha Chemical Co., Ltd.), 2-hydroxyethyl methacrylate (reagent special grade, Wako Pure Chemical Industries, Ltd.) 7.56 g, and hexyl Mercaptan (special grade reagent, Wako Pure Chemical Industries, Ltd.) 18.9 g was added to a three-necked flask and heated to 60 ° C. with stirring in a nitrogen atmosphere. After 1 hour, 1.84 g of azoisobutyronitrile (reagent special grade, Wako Pure Chemical Industries, Ltd.) was dissolved in 80 g of toluene, and this was added dropwise to a three-necked flask. The mixture was heated at 60 ° C. for 21 hours, then heated to 115 ° C. and stirred for 2 hours. Then, the pressure was reduced and the solvent was distilled off. To this was added 200 g of methanol, and the mixture was shaken vigorously and allowed to stand for 30 minutes. A short process distillation purification was performed on the upper layer to obtain a polymer copolymer X. Subsequently, the polymer copolymer X and trimellitic acid triisodecyl (Kao Corporation) were mixed at a mass ratio of 2: 1 to prepare a dispersion medium X.

[Evaluation results]
As shown in Table 1, the coefficient (E / R) representing the change in viscosity with respect to the temperature of the dispersion medium X containing the acrylic resin is 1 × 10 ⁸ , whereas the coefficient (E / R) of silicone is any also at 8 × 10 ⁷ or less, change in viscosity with respect to temperature is smaller than the dispersion medium X. From this, it was suggested that the electromagnetic wave adjusting element using silicone as the second medium is superior in responsiveness in a wide temperature range as compared with the electromagnetic wave adjusting element using acrylic resin as the second medium. Moreover, the non volatile matter of each dispersion medium was 95 mass% or more.

[Example 2 Evaluation of transparency]
[Example 2-1]
(Preparation of conductive substrate with primer layer)
A primer on a conductive layer of a conductive substrate having an ITO film (average thickness 30 nm, surface resistance value 200Ω / □ to 700Ω / □) as a conductive layer on one side of a PET film (300R, Toyobo Co., Ltd., thickness 125 μm) A layer forming coating solution is applied to the entire surface using a bar coater, dried at 100 ° C./3 minutes, and then irradiated with 2,000 mJ / cm ² of ultraviolet rays using a metal halide lamp to form a primer layer. Thus, a conductive substrate with a primer layer was produced. The average thickness of the primer layer was 74 nm.

  The primer layer forming coating solution is a material containing AY42-151 (a urethane (meth) acrylate containing a pentaerythritol skeleton) in a mixed solution of 1-methoxy-2-propanol / isopropyl alcohol = 7/3 (mass ratio). Toray Dow Corning Co., Ltd.) was mixed to prepare a ratio of 98.5% by mass. The conductive substrate with a primer layer had a parallel line transmittance of 85.7% and a haze of 1.4%. Parallel line transmittance and haze were measured using a spectroscopic colorimetric haze meter (TC-1800H, Tokyo Denshoku Co., Ltd.). In addition, the blank in the measurement of parallel line transmittance and haze was air.

(Preparation of emulsion)
To a 9 mL sample tube, 1.8 g of urethane acrylate (UA-7100, Shin-Nakamura Chemical Co., Ltd.) was added, and 5.2 mg of bis (2,4,6-trimethylbenzoyl) pheniphosphine oxide ( A solution obtained by dissolving BASF Japan Ltd. in tetrahydrofuran (special grade reagent, Wako Pure Chemical Industries, Ltd.) was further added and stirred for 1 minute to prepare a first medium. Next, 0.2 g of dimethyl silicone (KF-96-100cs, Shin-Etsu Chemical Co., Ltd.) was added as the second medium, stirred for 5 minutes, degassed for 5 minutes, and the second medium was the first medium. An emulsion dispersed therein was prepared.

(Production and evaluation of evaluation laminate)
The prepared emulsion was coated on the primer layer of the conductive substrate with the primer layer using a bar coater. Next, another primer layer of the conductive substrate with a primer layer was placed on and adhered to the emulsion coating layer. Finally, 4,000 mJ / cm ² of ultraviolet rays were irradiated from one conductive substrate side using a metal halide lamp. Thus, the laminated body for evaluation in which the second medium is dispersed as a spherical droplet in the ultraviolet-cured first medium, and the resin layer having a thickness of 88 μm to 98 μm is sandwiched between the pair of conductive substrates. Was made. The overall thickness of the evaluation laminate was 338 μm to 348 μm.

  Subsequently, the parallel-line transmittance and haze of the evaluation laminate were measured using a spectroscopic colorimetric haze meter (TC-1800H, Tokyo Denshoku Co., Ltd.). In addition, the blank in the measurement of parallel line transmittance and haze was air.

  Furthermore, the difference between the refractive index after curing of the first medium used for the production of the evaluation laminate and the refractive index of the second medium was measured. The refractive index of the first medium after curing is measured with an Abbe refractometer (DR-A1, Atago Co., Ltd.), and the refractive index of the second medium is measured with a digital refractometer (RX-5000α, Atago Co., Ltd.). did. Each measurement was performed three times at 25 ° C., and the average of the three times was taken as the refractive index. The results are shown in Table 2.

[Example 2-2]
A laminate for evaluation was produced in the same manner as in Example 2-1, except that the same amount of dimethyldiphenyl silicone (KF-54, Shin-Etsu Chemical Co., Ltd.) was used as the second medium instead of dimethyl silicone. Then, the transparency was evaluated. The results are shown in Table 2.

[Example 2-3]
A laminate for evaluation was produced in the same manner as in Example 2-1, except that the same amount of aralkyl-modified silicone (KF-410, Shin-Etsu Chemical Co., Ltd.) was used instead of dimethyl silicone as the second medium. Then, the transparency was evaluated. The results are shown in Table 2.

[Example 2-4]
A laminate for evaluation was produced in the same manner as in Example 2-1, except that the same amount of dimethyldiphenyl silicone (KF-53, Shin-Etsu Chemical Co., Ltd.) was used as the second medium instead of dimethyl silicone. Then, the transparency was evaluated. The results are shown in Table 2.

[Example 2-5]
The same as Example 2-1 except that the same amount of alkyl aralkyl-modified silicone (XF-42-334, Momentive Performance Materials Japan GK) was used as the second medium instead of dimethyl silicone. Thus, a laminate for evaluation was prepared and the transparency was evaluated. The results are shown in Table 2.

[Example 2-6]
In the preparation of the first medium, the evaluation laminate was prepared in the same manner as in Example 2-1, except that the same amount of urethane acrylate (UF-07DF, Kyoeisha Chemical Co., Ltd.) was used instead of UA-7100. Fabricated and evaluated for transparency. The results are shown in Table 2.

[Example 2-7]
A laminate for evaluation was produced in the same manner as in Example 2-6 except that the same amount of dimethyldiphenyl silicone (KF-54, Shin-Etsu Chemical Co., Ltd.) was used as the second medium instead of dimethyl silicone. Then, the transparency was evaluated. The results are shown in Table 2.

[Example 2-8]
A laminate for evaluation was produced in the same manner as in Example 2-6 except that the same amount of aralkyl-modified silicone (KF-410, Shin-Etsu Chemical Co., Ltd.) was used instead of dimethyl silicone as the second medium. Then, the transparency was evaluated. The results are shown in Table 2.

[Example 2-9]
A laminate for evaluation was produced in the same manner as in Example 2-6 except that the same amount of dimethyldiphenyl silicone (KF-53, Shin-Etsu Chemical Co., Ltd.) was used as the second medium instead of dimethyl silicone. Then, the transparency was evaluated. The results are shown in Table 2.

[Evaluation results]
As shown in Table 2, Examples 2-2 to 2-5 and 2-7 to 2-9 using specific silicone as the second medium used silicone that does not correspond to the specific silicone as the second medium. Compared with Examples 2-1 and 2-6, the refractive index difference between the first medium and the second medium after curing was small, the parallel line transmittance was large, and the haze was small. From this, it was suggested that the element for electromagnetic wave adjustment excellent in transparency is obtained by using specific silicone as a 2nd medium.

[Example 3 Formation of interface layer and its evaluation]
[Example 3-1]
(Production of evaluation substrate)
In a 9 mL sample tube, 0.7 g of the polymer copolymer X used in the preparation of the dispersion medium X in Example 1 as the first medium and dimethyldiphenyl silicone (KF-54, Shin-Etsu Chemical) as the second medium. Kogyo Co., Ltd.) 0.3 g was added, stirred for 5 minutes and vacuum degassed for 5 minutes. The obtained mixture was applied to a substrate using a bar coater so as to have a film thickness of 30 μm, thereby preparing an evaluation substrate. A soda lime glass plate was used as the substrate.

(Measurement of average droplet diameter)
The evaluation substrate immediately after the production is observed with an optical microscope (BXFM-A, DP73, LS5040, Olympus Corporation), and a photographed image in a state where the second medium is dispersed in the form of droplets in the first medium. Obtained. 100 droplets were arbitrarily selected from the photographed image, the diameter was measured using analysis software (WinROOF2013, Mitani Corp.), and the average value was defined as the average droplet diameter. The results are shown in Table 3.

[Example 3-2]
In an ampule tube, dodecyl methacrylate (Kyoeisha Chemical Co., Ltd.) 22.0 g, methacryloyl-terminated polydimethylsilicone (FM-0721, JNC Co., Ltd.) 8.8 g, thioglycolic acid (Wako Pure Chemical Industries, Ltd.) 0.13 g, And 0.14 g of azoisobutyronitrile (Wako Pure Chemical Industries, Ltd.) were added together with 50 g of benzene (Kanto Chemical Co., Ltd.). Subsequently, freeze deaeration is performed 5 times, and the tube is sealed and vacuum dried at 60 ° C. for 48 hours, whereby the degree of polymerization of dodecyl methacrylate is 100, the degree of polymerization of dimethyl silicone is 67, and dimethyl silicone to dodecyl methacrylate. A surfactant 1 having three modifications was synthesized.

  A substrate for evaluation was prepared in the same manner as in Example 3-1, except that 0.02 g of surfactant 1 was further added to a 9 mL sample tube, and the average droplet diameter was measured. The results are shown in Table 3.

[Example 3-3]
In an ampule tube, dodecyl methacrylate (Kyoeisha Chemical Co., Ltd.) 15.0 g, methacryloyl-terminated polydimethyl silicone (FM-0721, JNC Co., Ltd.) 15.0 g, thioglycolic acid (Wako Pure Chemical Industries, Ltd.) 0.09 g, And 0.10 g of azoisobutyronitrile (Wako Pure Chemical Industries, Ltd.) were added together with 50 g of benzene (Kanto Chemical Co., Inc.). Subsequently, freeze deaeration is performed 5 times, and the tube is sealed and vacuum dried at 60 ° C. for 48 hours, whereby the degree of polymerization of dodecyl methacrylate is 100, the degree of polymerization of dimethyl silicone is 67, and dimethyl silicone to dodecyl methacrylate. A surfactant 2 having 5 modifications was synthesized.

  An evaluation substrate was prepared in the same manner as in Example 3-2 except that the same amount of surfactant 2 was used in place of surfactant 1, and the average droplet diameter was measured. The results are shown in Table 3.

[Example 3-4]
In an ampule tube, dodecyl methacrylate (Kyoeisha Chemical Co., Ltd.) 22.0 g, methacryloyl-terminated polydimethyl silicone (FM-0721, JNC Co., Ltd.) 4.4 g, thioglycolic acid (Wako Pure Chemical Industries, Ltd.) 0.13 g, And 0.14 g of azoisobutyronitrile (Wako Pure Chemical Industries, Ltd.) were added together with 50 g of benzene (Kanto Chemical Co., Ltd.). Subsequently, freeze deaeration is performed 5 times, and the tube is sealed and vacuum dried at 60 ° C. for 48 hours, whereby the degree of polymerization of dodecyl methacrylate is 100, the degree of polymerization of dimethyl silicone is 67, and dimethyl silicone to dodecyl methacrylate. A surfactant 3 having one modification was synthesized.

  A substrate for evaluation was prepared in the same manner as in Example 3-2 except that the same amount of surfactant 3 was used in place of surfactant 1, and the average droplet diameter was measured. The results are shown in Table 3.

[Example 3-5]
In an ampoule tube, 22.0 g of dodecyl methacrylate (Kyoeisha Chemical Co., Ltd.), methacryloyl-terminated polydimethylsilicone (FM-0721, JNC Corporation) 8.8 g, thioglycolic acid (Wako Pure Chemical Industries, Ltd.) 0.26 g, And 0.14 g of azoisobutyronitrile (Wako Pure Chemical Industries, Ltd.) were added together with 50 g of benzene (Kanto Chemical Co., Ltd.). Subsequently, freeze deaeration is performed 5 times, and the tube is sealed and vacuum dried at 60 ° C. for 48 hours, whereby the degree of polymerization of dodecyl methacrylate is 50, the degree of polymerization of dimethyl silicone is 67, and dimethyl silicone to dodecyl methacrylate. A surfactant 4 having one modification was obtained.

  A substrate for evaluation was prepared in the same manner as in Example 3-2 except that the same amount of surfactant 4 was used in place of surfactant 1, and the average droplet diameter was measured. The results are shown in Table 3.

[Example 3-6]
In an ampule tube, 18.0 g of dodecyl methacrylate (Kyoeisha Chemical Co., Ltd.), methacryloyl-terminated polydimethylsilicone (FM-0721, JNC Corporation) 12.0 g, thioglycolic acid (Wako Pure Chemical Industries, Ltd.) 0.36 g, And 0.12 g of azoisobutyronitrile (Wako Pure Chemical Industries, Ltd.) were added together with 50 g of benzene (Kanto Chemical Co., Ltd.). Subsequently, freeze deaeration is performed 5 times, and the tube is sealed and vacuum dried at 60 ° C. for 48 hours, whereby the degree of polymerization of dodecyl methacrylate is 33, the degree of polymerization of dimethyl silicone is 67, and dimethyl silicone into dodecyl methacrylate. Surfactant 5 having one modification was obtained.

  A substrate for evaluation was prepared in the same manner as in Example 3-2 except that the same amount of surfactant 5 was used in place of surfactant 1, and the average droplet diameter was measured. The results are shown in Table 3.

[Example 3-7]
A substrate for evaluation was prepared in the same manner as in Example 3-4 except that the amount of the surfactant 3 was changed to 0.08 g, and the average droplet diameter was measured. The results are shown in Table 3.

[Evaluation results]
As shown in Table 3, Examples 3-2 to 3-7, in which a surfactant was added to the mixture of the first medium and the second medium, were surface active in the mixture of the first medium and the second medium. The average droplet diameter was smaller than that of Example 3-1 to which no agent was added. From this, it was suggested that the formation of the interface layer between the first medium and the second medium suppresses the coalescence of the droplets of the second medium.

[Example 4 Confirmation of operation of electromagnetic wave adjusting particles in second medium]
(Preparation of electromagnetic wave adjusting particles)
An 8.5 mass% iodine isoamyl acetate solution was prepared from iodine (JIS reagent special grade, Wako Pure Chemical Industries, Ltd.) and isoamyl acetate (reagent special grade, Wako Pure Chemical Industries, Ltd.), and nitrocellulose (1/4 LIG, Verge). A 20.0 mass% nitrocellulose isoamyl acetate solution was prepared from Luck NC) and isoamyl acetate. Calcium iodide hydrate (chemical use, Wako Pure Chemical Industries, Ltd.) was dried by heating, dehydrated and dissolved in isoamyl acetate to prepare a 20.9 mass% calcium iodide solution. A 20 L flask was equipped with a stirrer and a condenser, 6905 g of iodine solution and 8723 g of nitrocellulose solution were added, and the flask was heated at a water bath temperature of 35 ° C. to 40 ° C. The water ratio (% by mass) in the nitrocellulose solution was measured using Hiranuma Sangyo Co., Ltd., Hiranuma moisture measuring device AQ-7 (generated liquid: Hydranal Aqualite RS, counter electrode liquid: Aqualite CN). The amount of water in the nitrocellulose solution was 53.2 g based on the added solution mass.

  After the temperature of the flask contents reached 35 ° C. to 40 ° C., 260 g of dehydrated methanol (special grade reagent, Wako Pure Chemical Industries, Ltd.) and 55.6 g of purified water (Wako Pure Chemical Industries, Ltd.) were added and stirred. To this, 1643 g of calcium iodide solution was added, and then 390 g of pyrazine-2,5-dicarboxylic acid (Hitachi Chemical Techno Service Co., Ltd.) was added. The water bath temperature was set to 42 ° C. to 44 ° C. and the mixture was stirred for 4 hours and then allowed to cool. The resulting synthesis solution is centrifuged at 9260 G for 5 hours, and the supernatant is removed by inclining. To the precipitate remaining at the bottom, isoamyl acetate corresponding to 5 times the mass of the precipitate is added, and the precipitate is ultrasonicated. Distributed. Next, after centrifuging at 710 G for 10 minutes, the supernatant was centrifuged at 9260 G for 3 hours. Inclined again, the supernatant was removed, and isoamyl acetate corresponding to 5 times the mass of the precipitate was added to the precipitate remaining at the bottom, and the precipitate was dispersed with ultrasound to obtain isoamyl acetate of polyiodide as electromagnetic wave adjusting particles. A dispersion was prepared.

  The polyiodide obtained was in the form of particles, the average length of 100 arbitrarily selected particles observed with a transmission electron microscope was 350 nm, and the average aspect ratio was 1/7. Met.

(Synthesis of particle dispersant)

  50 g of toluene (special grade reagent, Wako Pure Chemical Industries, Ltd.), 3 g of methacrylic acid (special grade reagent, Wako Pure Chemical Industries, Ltd.), 7 g of methacrylic terminal dimethyl silicone (FM0721, JNC Corp., weight average molecular weight: 5,000) Then, 0.057 g of azoisobutyronitrile (reagent special grade, Wako Pure Chemical Industries, Ltd.) was added and dissolved, and freeze degassing was performed three times, followed by nitrogen substitution. After heating to 60 ° C. in a water bath and carrying out a polymerization reaction for 24 hours, the polymerization was stopped by cooling in an ice bath. Thereafter, freeze-drying is performed for 1 day, vacuum drying is performed at room temperature (25 ° C.) for 3 days, and vacuum drying is performed for 1 day at 60 ° C., and a structural unit containing a carboxy group as a functional group capable of interacting with the surface of the electromagnetic wave adjusting particles; A copolymer having a structural unit containing a siloxane bond was prepared as a particle dispersant.

(Preparation of electromagnetic wave adjusting particle dispersion)
In an eggplant flask, 1 g of the particle dispersant was dissolved in 10 g of hexane, and 20 g of acetone was further added to prepare a particle dispersant solution. This was added to 10 g of polyiodide isoamyl acetate dispersion (5% by mass), and further 10 g of hexane was added. While heating the eggplant flask to 50 ° C. to 60 ° C. in a hot water bath, the solvent was distilled off with an evaporator, and when the amount of the solvent became about half of the initial amount, the solvent distillation was stopped. 20 g of hexane was added, and the solvent was distilled off with an evaporator while heating the eggplant flask to 50 ° C. to 60 ° C. again in a hot water bath. When the amount of the solvent became about half of the initial amount, the solvent distillation was stopped. The process of adding hexane and evaporating the solvent was repeated twice more to convert the solvent from isoamyl acetate to hexane. Next, 49.5 g of dimethyl silicone (KF-96, viscosity: 10 mPa · s, Shin-Etsu Chemical Co., Ltd.) is added as a second medium, and the solvent is distilled off with an evaporator to prepare an electromagnetic wave adjusting particle dispersion. did.

(Preparation of electromagnetic wave adjusting element for evaluation)
Using the electromagnetic wave adjusting particle dispersion obtained above, an electromagnetic wave adjusting element for evaluation was produced as follows. In addition, the electromagnetic wave adjustment particle dispersion was prepared within 24 hours.

  As a conductive substrate, two glass plates (special order product, Geomat Co., Ltd., thickness 0.7 mm) having a surface electrical resistance value of 100 ± 50Ω / □ having a conductive layer (thickness 25 nm) made of ITO on one side were prepared. . Spacer beads were applied on the conductive layer of one conductive substrate so that the cell gap was 50 μm. Another conductive substrate was placed thereon.

  For evaluation, the electromagnetic wave adjusting particle dispersion is brought into contact with the gap between the two conductive substrates, the electromagnetic wave regulator dispersion is filled by capillary action, and the conductive substrate end is sealed with an epoxy resin. An electromagnetic wave adjusting element was produced.

  About the electromagnetic wave adjustment element for evaluation obtained above, an AC power source was connected to the conductive layer of the conductive substrate, and the light transmittance of the electromagnetic wave adjustment element was measured when the AC voltage was applied and when it was not applied. A spectroscopic color difference meter (SZ-Σ90, Nippon Denshoku Industries Co., Ltd.) was used for the measurement, and the Y value (%) measured with an A light source and a viewing angle of 2 degrees was used as the light transmittance. The measurement was performed in an environment at 25 ° C.

  The light transmittance of the electromagnetic wave adjusting element for evaluation was 0.7% and a deep blue color when no AC voltage was applied (when no voltage was applied). Moreover, the light transmittance of the evaluation electromagnetic wave adjusting element when an AC voltage of 50 Hz of 30 V (effective value) was applied was 23%, and the light transmittance when a voltage of 50 V was applied was 32%. From the above, it was confirmed that the electromagnetic wave adjusting particles operate normally when silicone is used as the second medium.

  1: power supply, 2: switch, 3: electromagnetic wave adjusting element, 4: conductive base material, 5: base material, 6: conductive layer, 7: primer layer, 9: second medium, 10: electromagnetic wave adjusting particle, 11 : First medium, 12: electromagnetic wave adjusting layer, 13: electromagnetic wave

Claims (10)

  A first medium curable by energy ray irradiation, a second medium containing silicone and dispersed in the first medium, and electromagnetic wave adjusting particles dispersed in the second medium, Electromagnetic wave adjustment material.   The electromagnetic wave adjusting material according to claim 1, wherein the first medium contains a compound having a (meth) acryloyl group.   The electromagnetic wave adjusting material according to claim 1, wherein the silicone includes a silicone having a substituent other than a methyl group or a hydrogen atom bonded to a silicon atom.   The electromagnetic wave adjusting material according to any one of claims 1 to 3, wherein the second medium has a viscosity at 25 ° C of 100 mPa · s to 3,000 mPa · s. 5. The electromagnetic wave adjusting material according to claim 1, wherein the second medium has an Andrade equation coefficient E / R of 9.0 × 10 ⁷ or less with respect to temperature and viscosity.   The electromagnetic wave adjusting material according to any one of claims 1 to 5, wherein a ratio of a nonvolatile content of the second medium is 95.00% by mass or more.   The electromagnetic wave adjusting material according to any one of claims 1 to 6, further comprising an interface layer between the first medium and the second medium.   It has an electromagnetic wave adjustment layer formed from an electromagnetic wave adjustment material of any one of Claims 1-7 arrange | positioned between a pair of electroconductive base materials and the said pair of electroconductive base materials. Electromagnetic wave adjustment element.   A pair of conductive substrates, and an electromagnetic wave adjusting layer disposed between the pair of conductive substrates, the electromagnetic wave adjusting layer including a cured first medium and silicone. An electromagnetic wave adjusting element comprising: a second medium dispersed in one medium; and electromagnetic wave adjusting particles dispersed in the second medium.   An electromagnetic wave preparation layer comprising: a cured first medium; a second medium containing silicone and dispersed in the first medium; and electromagnetic wave adjusting particles dispersed in the second medium. An electromagnetic wave adjusting element.