Transducer

Abstract

To provide a transducer that comprises a dielectric layer having a high dielectric constant and high flexibility.SOLUTION: A transducer has a dielectric layer. The dielectric layer has a dielectric constant of 8.0 or more at a frequency of 1 kHz. The dielectric layer includes a urethane elastomer, a structure of a cyclic multidentate ligand, an anion structure, and a cation structure.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to transducers. [Background technology]

[0002] Transducers, consisting of a dielectric layer and at least two electrodes sandwiching the dielectric layer, are being applied in various fields as elements that utilize the deformation (expansion and contraction) of the dielectric layer to convert electrical energy and mechanical energy with high conversion efficiency. For example, when the electrical energy generated by the deformation of the dielectric layer due to an external force is obtained as output, they can be used as sensors or power generation elements. They can also function as actuators by generating stress in the dielectric layer by applying a potential difference between a pair of electrodes.

[0003] When a dielectric layer is used for such sensor applications, actuator applications, and power generation applications, it is preferable that the dielectric layer has a high dielectric constant from the viewpoint of increasing conversion efficiency, and that the dielectric layer has flexibility from the viewpoint of ease of deformation. For example, Patent Document 1 discloses a transducer that uses an elastomer containing barium titanate particles as a dielectric layer, and Patent Document 2 discloses a capacitance-type sensor that uses urethane foam as a dielectric layer. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2013 / 058237 [Patent Document 2] Japanese Patent Application Publication No. 2019-124506 [Non-patent literature]

[0005] [Non-Patent Document 1] Sustainability 2021, 13(17), 9881 [Non-patent document 2] IEEE Transactions on SYSTEMS,MAN AND CYBERNETICS, Vol. SMC-9, No.1,January 1979,pp.62-66 Summary of the Invention [Problem to be solved by the invention]

[0006] However, although the dielectric layer disclosed in Patent Document 1 uses a flexible elastomer, it contains a large amount of barium titanate to increase the dielectric constant, resulting in a high modulus of elasticity of the dielectric layer. On the other hand, the dielectric layer disclosed in Patent Document 2 is composed only of flexible urethane foam, but the urethane foam has a low dielectric constant, and the thickness of the urethane foam is a thin film of 1 mm or less to improve the sensitivity of the sensor.

[0007] As such, it has been difficult to achieve all the required properties when using a dielectric layer as a transducer. At least one aspect of the present disclosure is directed to a transducer that is capable of converting mechanical energy into electrical energy and / or converting mechanical energy into electrical energy, and that includes a dielectric layer that has a high dielectric constant and high flexibility. [Means for solving the problem]

[0008] At least one aspect of the present disclosure provides a transducer capable of converting mechanical energy to electrical energy and / or electrical energy to mechanical energy, comprising: the transducer having a dielectric layer; The dielectric layer has a relative dielectric constant of 8.0 or more at a frequency of 1 kHz, The present invention relates to a transducer in which the dielectric layer satisfies any one of the following (i) to (vi): (i) the dielectric layer comprises a urethane elastomer, an ionic liquid, and a cyclic multidentate ligand; (ii) the dielectric layer comprises a urethane elastomer, a cyclic multidentate ligand, and an anion, and the urethane elastomer has a cation structure in its molecule; (iii) the dielectric layer contains a urethane elastomer, a cyclic multidentate ligand, and a cation, and the urethane elastomer has an anionic structure in its molecule; (iv) the dielectric layer comprises a urethane elastomer and an ionic liquid, and the urethane elastomer has a cyclic multidentate ligand structure in its molecule; (v) the dielectric layer comprises a urethane elastomer and an anion, and the urethane elastomer has a cyclic multidentate ligand structure and a cation structure in its molecule; (vi) The dielectric layer contains a urethane elastomer and a cation, and the urethane elastomer has a cyclic multidentate ligand structure and an anion structure in the molecule. [Effects of the Invention]

[0009] According to at least one aspect of the present disclosure, there is provided a transducer capable of converting mechanical energy to electrical energy and / or converting mechanical energy to electrical energy, the transducer comprising a dielectric layer having a high dielectric constant and high flexibility. [Brief explanation of the drawings]

[0010] [Figure 1] Schematic diagram showing the mechanism for improving the relative permittivity of the dielectric layer according to the present disclosure. [Figure 2] Schematic diagram illustrating a method for manufacturing a dielectric layer according to the present disclosure. [Figure 3] Schematic diagram of a transducer according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0011] In the present disclosure, expressions such as "XX or more and YY or less" or "XX to YY" that represent a numerical range mean a numerical range including the lower and upper limits, which are the endpoints, unless otherwise specified. When a numerical range is described in stages, the upper and lower limits of each numerical range can be arbitrarily combined. In the present disclosure, for example, a description such as "at least one selected from the group consisting of XX, YY, and ZZ" means any of XX, YY, ZZ, a combination of XX and YY, a combination of XX and ZZ, a combination of YY and ZZ, or a combination of XX, YY, and ZZ.

[0012] Hereinafter, embodiments of the present disclosure will be described. Note that the embodiments described below are merely examples, and the present disclosure is not limited to these embodiments.

[0013] <Dielectric layer> In at least one embodiment of the present disclosure, the dielectric layer satisfies any one of the following (i) to (vi). (i) The dielectric layer includes a urethane elastomer, an ionic liquid, and a cyclic multidentate ligand. (ii) The dielectric layer comprises a urethane elastomer, a cyclic multidentate ligand, and an anion, and the urethane elastomer has a cationic structure in the molecule. (iii) The dielectric layer contains a urethane elastomer, a cyclic multidentate ligand, and a cation, and the urethane elastomer has an anionic structure in the molecule. (iv) The dielectric layer comprises a urethane elastomer and an ionic liquid, and the urethane elastomer has a cyclic multidentate ligand structure in the molecule. (v) the dielectric layer comprises a urethane elastomer and an anion, The monomer has a cyclic multidentate ligand structure and a cation structure in the molecule. (vi) The dielectric layer contains a urethane elastomer and a cation, and the urethane elastomer has a cyclic multidentate ligand structure and an anion structure in the molecule.

[0014] First, (i) the case where the dielectric layer contains a urethane elastomer, an ionic liquid, and a cyclic multidentate ligand will be described. The present inventors have found that a dielectric layer containing a urethane elastomer, an ionic liquid, and a cyclic multidentate ligand can exhibit a high relative dielectric constant. The present inventors believe that the mechanism by which this occurs is as follows.

[0015] The improvement in the dielectric constant in the present disclosure is believed to be due to the increase in the distance between the cation and anion ion pairs in the ionic liquid, leading to the progression of ionic polarization. The mechanism by which the dielectric constant of the dielectric layer is improved will be explained using Figures 1A to 1C. Figures 1A to 1C show an example of 18-crown-6-ether as a cyclic multidentate ligand.

[0016] First, when an ionic liquid is contained in a urethane elastomer (Figure A), the nitrogen atoms derived from the urethane bonds in the urethane elastomer electrically interact with the cations in the ionic liquid through their lone electron pairs, reducing the molecular mobility of the ionic liquid (Figure 1B). This reduction in molecular mobility of the ionic liquid makes it easier for cyclic multidentate ligands with high coordination ability for cations to coordinate to the cations in the ionic liquid. When a cyclic multidentate ligand coordinates with the cation of an ionic liquid to form a complex, the distance between the cation and anion ion pairs of the ionic liquid increases (Figure 1C), increasing the ionic polarization of the ionic liquid and resulting in an improvement in the dielectric constant.

[0017] Therefore, for example, even if an ionic liquid and a cyclic multidentate ligand are blended with a silicone rubber that does not contain urethane bonds instead of a urethane elastomer, the high molecular mobility of the ionic liquid prevents the cyclic multidentate ligand from effectively coordinating with the cations of the ionic liquid, and the dielectric constant does not improve.

[0018] Furthermore, since it is believed that the formation of the complex increases the distance between the ion pairs, increasing ionic polarization and improving the relative permittivity, the effects of improving the relative permittivity and flexibility are not limited to when the dielectric layer contains an ionic liquid. For example, the urethane elastomer may have a cationic structure or an anionic structure in its molecule. That is, (ii) the dielectric layer may include a urethane elastomer, a cyclic multidentate ligand, and an anion, and the urethane elastomer may have a cationic structure in the molecule. In this case, the cyclic multidentate ligand may be coordinated to the cationic structure in the molecule. In addition, (iii) the dielectric layer may include a urethane elastomer, a cyclic multidentate ligand, and a cation, and the urethane elastomer may have an anionic structure in its molecule. In this case, in addition to the urethane bond, the anionic structure may affect the molecular mobility of the cation, allowing the cyclic multidentate ligand to coordinate.

[0019] Similarly, from the viewpoint of improving the relative permittivity and improving flexibility, the urethane elastomer may have a cyclic multidentate ligand in its molecule. That is, (iv) the dielectric layer may include a urethane elastomer and an ionic liquid, and the urethane elastomer may have a cyclic multidentate ligand in its molecule. In this case, too, it is believed that the molecular mobility of the ionic liquid is reduced by the urethane bond, and furthermore, the cyclic multidentate ligand in the urethane elastomer molecule coordinates to the cation of the ionic liquid, thereby achieving the above-mentioned effects.

[0020] Furthermore, the dielectric layer contains a urethane elastomer and any one ion selected from the group consisting of anions and cations, and the urethane elastomer has polycyclic rings in its molecule. In one embodiment, the complex has a dentate ligand and an ionic structure with a polarity opposite to that of the ionic structure in the molecule. More specifically, the following (v) and (vi) are included. (v) the dielectric layer comprises a urethane elastomer and an anion, and the urethane elastomer has a cyclic multidentate ligand structure and a cation structure in its molecule; (vi) The dielectric layer contains a urethane elastomer and a cation, and the urethane elastomer has a cyclic multidentate ligand structure and an anion structure in the molecule.

[0021] <Urethane elastomer> Urethane elastomers are elastomers obtained mainly from polyols, polyisocyanates, curing catalysts, chain extenders, and other additives. The polyol is not particularly limited as long as it has two or more hydroxyl groups in the molecule, and examples thereof include at least one selected from the group consisting of polyester polyols, polycarbonate polyols, polyether polyols, polycaprolactone polyols, polyolefin polyols, acrylic polyols, and the like.

[0022] Among these polyols, polycarbonate polyols and polyester polyols are preferred for use as transducers because the polycarbonate urethanes and polyester urethanes obtained by reacting them with polyisocyanates have excellent mechanical strength, abrasion resistance, and dielectric breakdown resistance. The polyol preferably contains at least one selected from the group consisting of polycarbonate polyols and polyester polyols. Furthermore, the urethane elastomer preferably contains at least one selected from the group consisting of polycarbonate urethanes and polyester urethanes. The proportion of the structure corresponding to the polyol in the urethane elastomer is preferably 60 to 90 mass %, more preferably 70 to 90 mass %.

[0023] Examples of polycarbonate polyols include polycarbonate polyols obtained by a condensation reaction of a diol component such as 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 3-methyl-1,5-pentanediol, diethylene glycol, 2-methyl-1,8-octanediol, polyethylene glycol, polypropylene glycol, or polytetramethylene glycol with a dialkyl carbonate such as phosgene or dimethyl carbonate, or a cyclic carbonate such as ethylene carbonate. These polycarbonate polyols may be used alone or in combination of two or more.

[0024] Examples of polyester polyols include polyester polyols obtained by condensation reaction of a diol component such as 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, or 1,9-nonanediol, or a triol component such as trimethylolpropane, with a dicarboxylic acid such as adipic acid, suberic acid, sebacic acid, phthalic anhydride, terephthalic acid, or hexahydroxyphthalic acid. These polyester polyols may be used alone or in combination of two or more.

[0025] The polyisocyanate to be reacted with the polyol is not particularly limited, but examples thereof include bifunctional isocyanates (diisocyanates) having two isocyanate groups, such as pentamethylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, xylylene diisocyanate, and diphenylmethane diisocyanate, and polymeric compounds of at least three isocyanates, such as a trimer compound of pentamethylene diisocyanate, a trimer compound of hexamethylene diisocyanate, and a polymeric compound of diphenylmethane diisocyanate (polymeric MDI). At least one selected from the group consisting of polyisocyanates having an isocyanate group can be used.

[0026] It is preferable to use a polyisocyanate in combination with a bifunctional isocyanate having two isocyanate groups, such as xylylene diisocyanate, and a polyisocyanate having at least three isocyanate groups, such as polymeric MDI. That is, the polyisocyanate preferably contains a bifunctional isocyanate and a polyisocyanate having at least three isocyanate groups. The above-mentioned combined use allows for control of crosslink density, which is preferable from the viewpoint of flexibility. The proportion of the structure corresponding to the difunctional isocyanate in the urethane elastomer is preferably 2 to 10% by mass, more preferably 3 to 8% by mass. The proportion of the structure corresponding to the polyisocyanate having at least three isocyanate groups in the urethane elastomer is preferably 3 to 15 mass %, more preferably 4 to 8 mass %.

[0027] Curing catalysts for urethane elastomers include urethane catalysts for promoting elastomerization (resinization) and isocyanurate catalysts, and in the present disclosure, these may be used alone or in combination.

[0028] Examples of urethane catalysts include tin-based urethane catalysts such as dibutyltin dilaurate and stannous octoate, and amine-based urethane catalysts such as triethylenediamine, tetramethylguanidine, pentamethyldiethylenetriamine, diethylimidazole, tetramethylpropanediamine, N,N,N'-trimethylaminoethylethanolamine, and 1,4-diazabicyclo[2.2.2]octane-2-methanol. These catalysts may be used alone or in combination. Among these urethane catalysts, triethylenediamine and 1,4-diazabicyclo[2.2.2]octane-2-methanol are preferred because they particularly accelerate the urethane reaction.

[0029] Examples of isocyanurate catalysts include metal oxides such as LiO and (BuSn)O, hydride compounds such as NaBH, alkoxide compounds such as NaOCH, KO-(t-Bu), and borates, amine compounds such as N(CH), N(CH)CHCH, and 1,4-ethylenepiperazine (DABCO), alkaline carboxylate salt compounds such as HCOONa, NaCO, PhCOONa / DMF, CHCOOK, (CHCOO)Ca, alkali soap, and naphthenate, alkaline formate compounds, and quaternary ammonium salt compounds such as ((R)-NR'OH)-OCOR". These may be used alone or in combination. Alternatively, N,N,N'-trimethylaminoethylethanolamine may be used, which acts alone as a urethanization catalyst and also acts as an isocyanuration catalyst.

[0030] If necessary, a chain extender (a polyfunctional low molecular weight polyol) may be used. Examples of the chain extender include glycols having a number average molecular weight of 1,000 or less.

[0031] Examples of glycols include ethylene glycol (EG), diethylene glycol (DEG), propylene glycol (PG), dipropylene glycol (DPG), 1,4-butanediol (1,4-BD), 1,6-hexanediol (1,6-HD), 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, xylylene glycol (terephthalyl alcohol), and triethylene glycol.

[0032] Examples of chain extenders other than glycols include trihydric or higher polyhydric alcohols. Examples of trihydric or higher polyhydric alcohols include trimethylolpropane, glycerin, pentaerythritol, and sorbitol. These may be used alone or in combination. It may also be used as such. If necessary, additives such as conductive agents, pigments, plasticizers, waterproofing agents, antioxidants, ultraviolet absorbers, and light stabilizers may also be used in combination.

[0033] <Ionic liquid> Ionic liquids are salts composed of cations and anions that exist as liquids over a wide temperature range. For example, salts that have a melting point of 100°C or less can be obtained by using relatively large organic ions as the ionic species that make up the salt. Ionic liquids play a role in increasing the dielectric properties of the dielectric layer.

[0034] The cation is not particularly limited, but may be at least one selected from the group consisting of imidazolium ion, pyridinium ion, pyrrolidinium ion, ammonium ion, piperidinium ion, phosphonium ion, etc. Among these, at least one selected from the group consisting of ammonium ion and imidazolium ion is preferred. In other words, the ionic liquid is preferably at least one selected from the group consisting of ammonium-based ionic liquids and imidazolium-based ionic liquids.

[0035] Furthermore, imidazolium ions are preferred as cations. As described above, the lone electron pairs derived from urethane elastomers or cyclic multidentate ligands stabilize the cations in the ionic liquid, increasing the distance between the cation and anion ion pairs in the ionic liquid and resulting in high dielectric constant. In this respect, the Coulomb interaction between imidazolium ions and anions is relatively weaker than that of other cation skeletons, making it easier to increase the distance between the cation and anion ion pairs in the ionic liquid, and thus a high level of dielectric constant can be expected.

[0036] The imidazolium ion may be at least one selected from the group consisting of 1-ethyl-3-methylimidazolium, 1-butyl-3-methylimidazolium, 1-ethyl-2,3-dimethylimidazolium, 1-butyl-2,3-dimethylimidazolium, 1-hexyl-2,3-dimethylimidazolium, 1,3-bis(2-hydroxyethyl)imidazolium, 1-(2-hydroxyethyl)-3-methylimidazolium, 1-(3-hydroxypropyl)-3-methylimidazolium, 1-butyl-3-(2-hydroxyethyl)imidazolium, 1-ethyl-3-(2-hydroxyethyl)imidazolium, and the like.

[0037] The ammonium ion may be at least one selected from the group consisting of quaternary ammonium salts such as methyltri-N-octylammonium, N-trimethyl-N-propylammonium, N-trimethyl-N-butylammonium, bis(2-hydroxyethyl)-methyl-octylammonium, bis(2-hydroxyethyl)-methyl-decylammonium, N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium, and N,N-(2-hydroxyethyl)-N-(9-octadecene)-N-methylammonium.

[0038] The anion is not particularly limited, but hydrogen sulfate anion (HSO4 - ), halogen ions, BF4 - , PF6 - , CF3SO3 - , (CF3SO2)2N - , (FSO2)2N - From the viewpoint of increasing the dielectric constant, it is preferable that the interaction between the cation and the anion is not strong. Therefore, the hydrogen sulfate anion (HSO4 - ), BF4 - , PF6 - , CF3SO3 - , (CF3SO2)2N - , (FSO2)2N -Particularly preferred is at least one selected from the group consisting of hydrogen sulfate anion (HSO4 - ), BF4 - , PF6 - , CF3SO3 - and (CF3SO2)2N - and at least one anion selected from the group consisting of:

[0039] Furthermore, the ionic liquid may have a reactive functional group in the cation or anion that reacts with an isocyanate group. Examples of reactive functional groups that react with an isocyanate group include hydroxyl groups. Such reactive functional groups allow the above-mentioned urethane elastomer to have a cationic or anionic structure in its molecule. Since the ionic liquid has a reactive functional group that reacts with an isocyanate group, it reacts with polyisocyanate, and the cationic or anionic structure is incorporated into the urethane elastomer molecule. By incorporating the cationic or anionic structure into the urethane elastomer molecule, it is possible to prevent the ionic liquid from bleeding out over time.

[0040] Specific examples of ionic liquids that can be suitably used in the present disclosure include 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, 1-hexyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, 1-ethyl-2,3-dimethylimidazolium bis(trifluoromethanesulfonyl)imide, and 1-butyl-2,3-dimethylimidazolium bis(trifluoromethanesulfonyl)imide. , 1-hexyl-2,3-dimethylimidazolium bis(trifluoromethanesulfonyl)imide, 1,3-bis(2-hydroxyethyl)imidazolium bis(trifluoromethanesulfonyl)imide, 1-(2-hydroxyethyl)-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, 1-(3-hydroxypropyl)-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, 1-ethyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide, 1-methyl 1-butyl-1-propylpyrrolidinium bis(trifluoromethanesulfonyl)imide, 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide, 1-ethylpyridinium bis(trifluoromethanesulfonyl)imide, 1-propylpyridinium bis(trifluoromethanesulfonyl)imide, 1-methyl-1-propylpiperidinium bis(trifluoromethanesulfonyl)imide, 1-butyl-1-methylpiperidinium bis(trifluoromethanesulfonyl)imide, N-trimethyl-N-propylammonium bis(trifluoromethanesulfonyl)imide, N-trimethyl-N-butylammonium bis(trifluoromethanesulfonyl)imide, bis(2-hydroxyethyl)-methyl-octylammonium bis(trifluoromethanesulfonyl)imide, bis(2-hydroxyethyl)-methyl-decylammonium bis(trifluoromethanesulfonyl)imide, N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium bis(trifluoromethanesulfonyl)imide, N,At least one selected from the group consisting of N-(2-hydroxyethyl)-N-(9-octadecene)-N-methylammonium bis(trifluoromethanesulfonyl)imide and the like can be mentioned.

[0041] Commercially available ionic liquids include, but are not limited to, "ELEXEL AS-110," "ELEXEL MP-442," "ELEXEL IL-210," "ELEXEL MP-471," "ELEXEL MP-456," and "ELEXEL AS-804" manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.; "HMI-FSI" manufactured by Mitsubishi Materials Corporation; "CIL-312," "CIL-542," and "CIL-612" manufactured by Nippon Carlit Co., Ltd.; and the IL-P series, IL-A series, IL-C series, IL-IM series, IL-AP series, and IL-OH series manufactured by Koei Chemical Co., Ltd.

[0042] The content of the ionic liquid in the dielectric layer is preferably 0.5 to 8.0 mass % based on the mass of the dielectric layer excluding the cyclic multidentate ligand. It is more preferably 1.7 to 8.0 mass %, even more preferably 2.0 to 8.0 mass %, and even more preferably 2.0 to 4.0 mass %. When the content of the ionic liquid is 0.5 mass % or more, a higher level of high dielectric constant can be expected compared to when the content is less than that. In addition, the content of the ionic liquid By setting the content to 8.0 mass % or less, the effect of increasing the dielectric constant relative to the content can be efficiently achieved. Furthermore, the content of the ionic liquid in the dielectric layer is preferably 0.5 to 7.0 mass%, more preferably 1.5 to 7.0 mass%, even more preferably 1.5 to 5.0 mass%, and even more preferably 1.6 to 4.0 mass%, based on the mass of the dielectric layer.

[0043] <Cyclic multidentate ligands> A cyclic multidentate ligand is a cyclic compound that has multiple lone electron pairs in one molecule and can form a complex by coordinate bonding with cations in an ionic liquid at two or more positions. There are no particular limitations on the cyclic multidentate ligand, but examples include crown ethers, calixarene compounds, porphyrins, and derivatives or modified forms thereof. These can be used alone or in combination of two or more types. The cyclic multidentate ligand can be at least one selected from the group consisting of crown ether compounds, calixarene compounds, and porphyrin compounds.

[0044] The crown ether compound preferably has a structure represented by formula (2): That is, the cyclic multidentate ligand preferably has a structure represented by formula (2). [ka]

[0045] In formula (2), n is an integer of 4 to 8, and R 2 represents an ethylene group or a phenylene group which may have a substituent, preferably an ethylene group. The substituent may be at least one selected from the group consisting of a hydroxymethyl group, a hydroxyethyl group, an aminomethyl group, an amino group, and a carboxy group. The substituent is preferably a hydroxymethyl group.

[0046] Specific examples of crown ether compounds that can be suitably used in the present disclosure include 12-crown 4-ether, 15-crown 5-ether, 18-crown 6-ether, 21-crown 7-ether, 24-crown 8 ether, benzo-12-crown 4-ether, benzo-15-crown 5-ether, benzo-18-crown 6-ether, benzo-21-crown 7-ether, benzo-24-crown 8-ether, dibenzo-12-crown 4-ether, dibenzo-15-crown 5-ether, dibenzo-18-crown 6-ether, dibenzo- At least one selected from the group consisting of 21-crown-7-ether, dibenzo-24-crown-8-ether, 2-hydroxymethyl-12-crown-4-ether, 2-hydroxymethyl-18-crown-6-ether, 2-hydroxyethyl-18-crown-6-ether, 2-aminomethyl-15-crown-5-ether, 4'-aminobenzo-15-crown-5-ether, 4'-aminobenzo-18-crown-6-ether, 4'-carboxybenzo-15-crown-5-ether, 4'-carboxybenzo-18-crown-6-ether, and the like can be mentioned.

[0047] The calixarene compound preferably has a structure represented by formula (3). That is, the cyclic multidentate ligand preferably has a structure represented by formula (3). [ka]

[0048] In formula (3), n is an integer of 4 to 6, and R 3 represents a hydrogen atom or any organic group. Examples of the organic group include -SO3H and alkyl groups having 1 to 8 carbon atoms (preferably 1 to 4 carbon atoms). Specific examples of calixarene compounds that can be suitably used in the present disclosure include calixarene compounds such as: calix[4]arene, calix[5]arene, calix[6]arene, 4-t-butylcalix[4]arene, 4-t-butylcalix[5]arene, 4-t-butylcalix[6]arene, 4-sulfocalix[4]arene, 4-sulfocalix[5]arene, 4-sulfocalix[6]arene, and the like.

[0049] The porphyrin compound has a structure represented by formula (4). [ka]

[0050] In formula (4), R 4 and R 5 R each independently represents a hydrogen atom or an arbitrary organic group. Examples of the organic group include an alkyl group having 1 to 8 carbon atoms and a phenyl group. A phenyl group is preferred. 5 is a hydrogen atom, and R 4 is preferably a phenyl group, that is, the porphyrin compound is preferably tetraphenylporphyrin.

[0051] Furthermore, among the cyclic polydentate ligands exemplified above, a cyclic polydentate ligand having a reactive functional group that reacts with an isocyanate group may be used. Such a reactive functional group allows the urethane elastomer to have a cyclic polydentate ligand in the molecule. A cyclic polydentate ligand having a reactive functional group that reacts with isocyanate groups reacts with polyisocyanate, and the cyclic polydentate ligand is incorporated into the urethane elastomer molecule. By incorporating the cyclic polydentate ligand into the urethane elastomer molecule, it is possible to prevent the cyclic polydentate ligand from bleeding out over time. Examples of reactive functional groups that react with isocyanate groups include hydroxyl groups.

[0052] Alternatively, an ionic liquid having a reactive functional group in a cation or anion that reacts with an isocyanate group, or a cyclic multidentate ligand having a reactive functional group that reacts with an isocyanate group may be used. These can result in an embodiment in which the dielectric layer contains a urethane elastomer and one ion selected from the group consisting of anions and cations, and the urethane elastomer molecule contains a cyclic multidentate ligand and an ionic structure with a polarity opposite to that of the ion.

[0053] The content of the cyclic multidentate ligand in the dielectric layer is preferably 1.0 to 8.0 times the molar amount of the ionic liquid, and more preferably 2.0 to 4.0 times. When the content of the cyclic multidentate ligand is 1.0 times or more, a higher level of high dielectric constant can be expected compared to when the content is less. Furthermore, when the content of the cyclic multidentate ligand is 8.0 times or less, the effect of increasing the dielectric constant relative to the content can be efficiently achieved.

[0054] <Dielectric constant> The dielectric layer has a relative permittivity of 8.0 or more. The relative permittivity of the dielectric layer is preferably 10.0 or more, more preferably 20.0 or more. Here, the relative permittivity in the present disclosure is the relative permittivity observed when an AC voltage of 1 kHz frequency is applied at room temperature. There is no particular upper limit to the relative permittivity. When the relative permittivity is within this range, it can be more suitably used as a dielectric layer for a transducer with excellent conversion efficiency between electrical energy and mechanical energy. The higher the relative permittivity, the more preferable, and there is no particular upper limit limit. The relative permittivity of the dielectric layer is preferably 8.0 to 100.0, more preferably 10.0 to 100.0, and even more preferably 20.0 to 100.0.

[0055] The reason for the dielectric constant at a frequency of 1 kHz is that, as mentioned above, the urethane elastomer and cyclic multidentate ligands electrically capture the cations in the ionic liquid, increasing the distance between the ion pairs in the ionic liquid and increasing ionic polarization. The magnitude of this ionic polarization is easily expressed as the dielectric constant at a frequency of 1 kHz.

[0056] The dielectric constant can be calculated from the measured impedance by applying a voltage to a dielectric layer sandwiched between two electrodes with a diameter of 1 mm or more. First, a four-terminal sample holder (SH2-Z type, manufactured by Toyo Corporation), an impedance analyzer (1260A, manufactured by Solartron), and a dielectric interface (1296A, manufactured by Solartron) are connected. Next, the dielectric layer is placed on the 10 mm lower electrode with a guard electrode so that it completely covers the electrode. The 20 mm upper electrode is then lowered until it touches the dielectric layer and then pushed in an additional 5 μm. A sweep is then performed at room temperature with an AC voltage of 0.1 Vpp and frequencies from 0.01 Hz to 1 MHz to calculate the dielectric constant at a frequency of 1 kHz.

[0057] <Method of manufacturing the dielectric layer> The dielectric layer can be synthesized, for example, by the following steps A(i) to A(iii). Step A(i): A step of obtaining a first mixture by mixing a polyol with a curing catalyst Step A(ii): A step of mixing an ionic liquid and a cyclic multidentate ligand with the first mixture to obtain a second mixture. Step A(iii): A mixture for forming a dielectric layer containing the second mixture and polyisocyanate is prepared. and then reacting the polyol (if the ionic liquid contains a reactive functional group that reacts with an isocyanate group, the ionic liquid), (if the cyclic multidentate ligand contains a reactive functional group that reacts with an isocyanate group, the cyclic multidentate ligand), and the polyisocyanate in the dielectric layer-forming mixture to form a dielectric layer.

[0058] One embodiment of a method for manufacturing the dielectric layer described above will be described below, however, the method for manufacturing the dielectric layer is not limited to this embodiment. In step A(i), a curing catalyst is mixed with a polyol to obtain a first mixture. As a mixing method for obtaining the first mixture, any known method such as mechanical stirring can be used.

[0059] In step A(ii), an ionic liquid and a cyclic multidentate ligand are mixed with the first mixture obtained in step A(i) to obtain a second mixture. The order in which the ionic liquid and the cyclic multidentate ligand are mixed is not particularly limited, and they may be mixed simultaneously, or a mixture of the ionic liquid and the cyclic multidentate ligand may be mixed in advance with the first mixture.

[0060] Finally, in step A(iii), a dielectric layer-forming mixture is prepared containing the second mixture prepared in step A(ii) and a polyisocyanate having at least two isocyanate groups. Next, the hydroxyl groups of the polyol in the dielectric layer-forming mixture (or the reactive functional groups of the ionic liquid if the ionic liquid contains a reactive functional group reactive with an isocyanate group) (or the reactive functional groups of the cyclic multidentate ligand if the cyclic multidentate ligand contains a reactive functional group reactive with an isocyanate group) are reacted with the isocyanate groups of the polyisocyanate. This forms a network structure via urethane bonds, resulting in the dielectric layer according to the present disclosure.

[0061] The method for forming the dielectric layer is not particularly limited, and examples thereof include molding, extrusion, injection molding, and coating molding. For example, in the molding method, a dielectric layer-forming mixture is injected through an injection port, heated to a temperature at which the dielectric layer-forming mixture hardens, and then demolded.

[0062] <Urethane elastomer with phase separation structure> The urethane elastomer may be a urethane elastomer having a phase-separated structure. The urethane elastomer has a matrix and domains dispersed in the matrix, and the matrix preferably contains at least one selected from the group consisting of polycarbonate urethane and polyester urethane, and the domains preferably have a structure represented by formula (1).

[0063] [ka] In formula (1), R 1represents an alkylene group having 3 to 5 carbon atoms.

[0064] In general, the polyether structure represented by formula (1) has weak intermolecular forces between ether groups, which allows the hardness to be kept extremely low, making it suitable for imparting flexibility to urethane elastomers.

[0065] In addition, polycarbonate urethane and polyester urethane obtained by reacting polycarbonate polyol or polyester polyol with polyisocyanate have strong intermolecular forces between carbonate groups and ester groups, and therefore have excellent mechanical strength, abrasion resistance, and insulation resistance. In addition to its excellent breakability, it also has the characteristic of being easily highly elastic.

[0066] When the urethane elastomer has a matrix containing at least one selected from the group consisting of polycarbonate urethane and polyester urethane, and domains dispersed in the matrix are polyols having the polyether structure represented by formula (1), it is possible to achieve both excellent flexibility and excellent recovery from deformation.

[0067] Urethane elastomers with a phase-separated structure have a matrix-domain structure (phase-separated structure) that allows the matrix and domains to each have different functions. The matrix provides recovery from deformation due to its high elastic modulus, while the domains primarily provide low hardness.

[0068] Furthermore, as will be described later, in the urethane elastomer according to the present disclosure, it is believed that the domains and the matrix are chemically bonded by urethane bonds at the boundary between them. Therefore, when a load applied to the urethane elastomer is removed, the recovery of the domains from deformation is thought to proceed in tandem with the recovery of the matrix from deformation. This is thought to give the urethane elastomer according to the present disclosure extremely high recovery from deformation. By using a urethane elastomer with such a matrix-domain structure, the dielectric layer exhibits softness and rapid recovery from deformation.

[0069] Furthermore, when urethane molding containing a urethane elastomer with a matrix-domain structure is mixed with an ionic liquid, it exhibits a higher dielectric constant than dielectric layers containing a urethane elastomer without a matrix-domain structure. The polyether structure of the domains captures and stabilizes the cations in the ionic liquid, reducing the interaction between ion pairs. This is thought to increase the average distance between ion pairs, thereby increasing the dipole orientation polarization.

[0070] The urethane elastomer can exhibit the above effect as long as it forms a matrix domain structure, and a part of the outer surface of the dielectric layer may be composed of the matrix, for example, or the entire outer surface of the dielectric layer may be composed of the matrix.

[0071] In cross-sectional observation of the dielectric layer using a scanning probe microscope, the area ratio of the domain area to the sum of the matrix area and the domain area [domain area / (matrix area+domain area)×100(%)] is preferably 8 to 55%, more preferably 10 to 50%, and even more preferably 20 to 40%.

[0072] The polycarbonate urethane and polyester urethane of the matrix in the urethane elastomer may be the same as the polycarbonate urethane and polyester urethane described above.

[0073] The number-average molecular weight of the raw material polycarbonate polyol and polyester polyol is preferably 500 to 10,000, and more preferably 700 to 8,000. When the number-average molecular weight is 500 or more, incompatibility with the domains is ensured, and phase separation between the matrix and the domains can be made clearer. Furthermore, by setting the number-average molecular weight to 10,000 or less, excessive viscosity increase of the polycarbonate polyol and polyester polyol can be prevented.

[0074] The number average molecular weight of polycarbonate polyol and polyester polyol can be calculated using standard polystyrene molecular weight conversion or the hydroxyl value (mgKOH / g) and valence. The number average molecular weight in terms of polystyrene molecular weight can be measured using high performance liquid chromatography. For example, a high-speed GPC apparatus (trade name: HLC-8220GPC, manufactured by Tosoh Corporation) is equipped with a column: Shodex GPCLF-804 (exclusion limit molecular weight: 2 x10 6 , Separation range: 3×10 2 ~2×10 6 ) can be measured using two in series.

[0075] When the hydroxyl value and valence are used, the number average molecular weight can be calculated using the following formula: For example, the number average molecular weight of a polyol with a hydroxyl value of 56.1 mg KOH / g and a valence of 2 can be calculated to be 2,000. Number average molecular weight = 56.1 x 1000 x valence ÷ hydroxyl value

[0076] Next, the polyether structure represented by formula (1) in the domain of the urethane elastomer will be described. In the structure represented by formula (1) in the domain, R 1represents an alkylene group having 3 to 5 carbon atoms. Preferably, R 1 represents an alkylene group having a branched structure and having 3 to 5 carbon atoms.

[0077] The polyether structure in formula (1) also has the effect of capturing and stabilizing the cations in the ionic liquid. 1 By R being an alkylene group having 3 to 5 carbon atoms, flexibility of the polymer chain is ensured. 1 When the alkylene group is a branched alkylene group having 3 to 5 carbon atoms, the intermolecular force between the ether groups is further reduced, and this is more preferable from the viewpoint of realizing low hardness.

[0078] R 1 For example, -(CH2) m -(m=3 to 5), -CH2CH(CH3)-, -CH2C(CH3)2CH2-, -CH2CH(CH3)CH2-, -(CH2)2CH(CH3)CH2-, etc. In the urethane elastomer, R 1 are all the same, but different R 1 It may be a combination of the above.

[0079] The number-average molecular weight (Mn) of the polyether structure represented by formula (1), as a repeating unit in the urethane elastomer, is preferably 1,000 to 50,000, more preferably 1,500 to 20,000. A number-average molecular weight of 1,000 or more is preferred because it ensures incompatibility with polycarbonate polyol and polyester polyol and results in clear phase separation between the matrix and domains of the resulting urethane elastomer. Furthermore, a number-average molecular weight of 50,000 or less is preferred because it facilitates domain formation and stabilizes the phase separation morphology.

[0080] The number average molecular weight of the polyether structure can be calculated in the same manner as the above-mentioned method for calculating the number average molecular weight of the polycarbonate polyol and polyester polyol. The chemical structures of the components contained in the matrix and domains can be analyzed using, for example, spectroscopic analyzers such as an AFM infrared spectroscopic analyzer, a microscopic infrared spectroscopic analyzer, or a microscopic Raman spectroscopic analyzer, or a mass spectrometer.

[0081] <Method of manufacturing a dielectric layer in which a urethane elastomer has a phase-separated structure> The dielectric layer in which the urethane elastomer has a phase-separated structure can be synthesized, for example, by the following steps B(i) to B(iv). The dielectric layer in which the urethane elastomer has a phase-separated structure is preferably a dielectric layer produced by a method including the following steps B(i) to B(iv).

[0082] Step B(i): A first urethane prepolymer having at least one (preferably at least two) isocyanate group is reacted with a first polycarbonate polyol and / or a first polyester polyol having at least two hydroxyl groups to produce at least two a step of obtaining a second urethane prepolymer having a hydroxyl group of Step B(ii): A step of obtaining a first dispersion by dispersing droplets containing at least a portion of the second urethane prepolymer in a second polycarbonate polyol and / or a second polyester polyol (which may be an excess unreacted portion of the first polycarbonate polyol or the first polyester polyol). Step B(iii): A step of obtaining a second dispersion by dispersing an ionic liquid and a cyclic multidentate ligand in the first dispersion. Step B(iv): preparing a mixture for forming a dielectric layer containing the second dispersion and a polyisocyanate having at least two isocyanate groups, and then reacting the second urethane prepolymer, the second polycarbonate polyol and / or the second polyester polyol, (the ionic liquid if the ionic liquid contains a reactive functional group that reacts with an isocyanate group), (the cyclic multidentate ligand if the cyclic multidentate ligand contains a reactive functional group that reacts with an isocyanate group), and the polyisocyanate having at least two isocyanate groups in the mixture for forming a dielectric layer to form a dielectric layer.

[0083] One embodiment of the method for producing the dielectric layer in which the urethane elastomer has a phase-separated structure described above will be described with reference to Fig. 2. However, the method for producing the dielectric layer in which the urethane elastomer has a phase-separated structure is not limited to this embodiment.

[0084] In step B(i), a first urethane prepolymer 11 having at least one (preferably at least two) isocyanate group is mixed with a first polycarbonate polyol 12 and / or a first polyester polyol 12 having at least two hydroxyl groups. Next, in the presence of a curing catalyst, the isocyanate group and the hydroxyl group in the resulting mixture are reacted to link them via a urethane bond, thereby obtaining a second urethane prepolymer 13 having at least two hydroxyl groups.

[0085] The first urethane prepolymer 11 is a polyether having at least one isocyanate group and a structure represented by formula (1). The first urethane prepolymer 11 can be obtained, for example, by the following process.

[0086] A polyether polyol having at least two hydroxyl groups and a structure represented by formula (1) is reacted with a polyisocyanate having at least two isocyanate groups. Examples of the polyether polyol include alkylene structure-containing polyether polyols such as polypropylene glycol, polytetramethylene glycol, a copolymer of tetrahydrofuran and neopentyl glycol, and a copolymer of tetrahydrofuran and 3-methyltetrahydrofuran, as well as random or block copolymers of these polyalkylene glycols. These may be used alone or in combination of two or more.

[0087] Among the polyether polyols, from the viewpoints of high ether group mobility, a high cation stabilizing effect, and the ability to achieve low hardness, it is preferable to contain at least one selected from polypropylene glycol, polytetramethylene glycol, a copolymer of tetrahydrofuran and neopentyl glycol, and a copolymer of tetrahydrofuran and 3-methyltetrahydrofuran.Furthermore, it is preferable to contain at least polypropylene glycol.

[0088] Examples of polyisocyanates that can be reacted with the polyether polyol include pentamethylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, trimer compounds (isocyanurates) or polymer compounds of these polyisocyanates, and allophanate polyisocyanates. Examples of the polyisocyanate include isocyanate, biuret type polyisocyanate, water-dispersible polyisocyanate, etc. These polyisocyanates may be used alone or in combination of two or more.

[0089] Among the polyisocyanates listed above, bifunctional isocyanates (diisocyanates) having two isocyanate groups are preferred due to their high compatibility with polyether polyols and ease of adjusting physical properties such as viscosity. Among the above polyisocyanates, it is more preferred to use at least one selected from hexamethylene diisocyanate, isophorone diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, xylylene diisocyanate, and diphenylmethane diisocyanate. Xylylene diisocyanate is even more preferred.

[0090] In the step of obtaining the first urethane prepolymer 11 by reacting the polyether polyol having the structure represented by formula (1) with the polyisocyanate, the isocyanate index is preferably 0.05 to 8.0, and more preferably 0.1 to 5.0. When the isocyanate index is within this range, the amount of components derived from the first urethane prepolymer that remain without forming a network structure can be reduced, and the exudation of liquid substances from the urethane elastomer can be suppressed.

[0091] The isocyanate index indicates the ratio ([NCO] / [OH]) of the number of moles of isocyanate groups in an isocyanate compound to the number of moles of hydroxyl groups in a polyol compound.

[0092] As the urethane catalyst for the first urethane prepolymer 11, the same catalyst as the curing catalyst for the urethane elastomer described above can be used.

[0093] In step B(ii), a dispersion is obtained in which droplets 14 containing at least a portion of the second urethane prepolymer are dispersed in the second polycarbonate polyol 14 and / or the second polyester polyol 14. Here, the second urethane prepolymer can be mixed with the second polycarbonate polyol and / or the second polyester polyol that are newly added in this step. Furthermore, excess unreacted material from the first polycarbonate polyol and / or the first polyester polyol in step B(i) can also be used as the second polycarbonate polyol and / or the second polyester polyol.

[0094] The first urethane prepolymer 11 contained in the second urethane prepolymer 13 is not compatible with the second polycarbonate polyol 15 and / or the second polyester polyol 15 and forms droplets 14 .

[0095] On the other hand, the first polycarbonate polyol and / or the first polyester polyol 12 contained in the second urethane prepolymer 13 is compatible with the second polycarbonate polyol 15 and / or the second polyester polyol 15 . Therefore, in the second polycarbonate polyol 15 and / or the second polyester polyol 15, droplets 14 containing first urethane prepolymer 11 constituting part of second urethane prepolymer 13 are uniformly and stably dispersed via the first polycarbonate polyol and / or the first polyester polyol 12. As a result, a first dispersion is obtained in which droplets 14 containing first urethane prepolymer 11 are dispersed in the second polycarbonate polyol 15 and / or the second polyester polyol 15.

[0096] In step B(ii), the second polycarbonate polyol 15 and / or the second polyester polyol 15 in which the droplets 14 are dispersed is the same as the first polycarbonate polyol used in step B(i). The second urethane prepolymer 13 may be an unreacted product of the carbonate polyol and / or the first polyester polyol with the first urethane prepolymer. That is, by using an excess amount of the first polycarbonate polyol and / or the first polyester polyol relative to the first urethane prepolymer in step B(i), a dispersion of the second urethane prepolymer 13 dispersed in the excess first polycarbonate polyol and / or the first polyester polyol (i.e., the second polycarbonate polyol 15 and / or the second polyester polyol 15) as described in step B(ii) can be obtained.

[0097] Even when an excess amount of the first polycarbonate polyol and / or first polyester polyol is used, it is possible to add additional polycarbonate polyol and / or polyester polyol (second polycarbonate polyol and / or second polyester polyol) as a dispersion medium for the second urethane prepolymer. In this case, the added polycarbonate polyol and / or polyester polyol may have the same chemical composition as or a different from the first polycarbonate polyol and / or first polyester polyol used in step B(i).

[0098] On the other hand, if the first polycarbonate polyol and / or first polyester polyol is reacted with the first urethane prepolymer in equivalent amounts in step B(i) and the first polycarbonate polyol and / or first polyester polyol is completely consumed, a dispersion is prepared in step B(ii) using a new polycarbonate polyol and / or polyester polyol as the second polycarbonate polyol and / or second polyester polyol. In this case, the polycarbonate polyol and / or polyester polyol used as the second polycarbonate polyol and / or second polyester polyol may have the same chemical composition as the first polycarbonate polyol and / or first polyester polyol, or may have a different chemical composition.

[0099] When excess unreacted material of the first polycarbonate polyol and / or the first polyester polyol is used as the second polycarbonate polyol and / or the second polyester polyol, step B(i) and step B(ii) can be carried out simultaneously.

[0100] In step B(iii), an ionic liquid and a cyclic multidentate ligand are dispersed in the first dispersion obtained in step B(ii) to obtain a second dispersion. The ionic liquid and the cyclic multidentate ligand may be mixed in any order, and may be mixed simultaneously, or a mixture of the ionic liquid and the cyclic multidentate ligand may be mixed in advance with the first mixture.

[0101] Finally, in step B(iv), a dielectric layer-forming mixture is prepared containing the second dispersion prepared in step B(iii) and a polyisocyanate having at least two isocyanate groups. Then, the terminal hydroxyl groups of the second urethane prepolymer 13 in the dielectric layer-forming mixture, the hydroxyl groups of the second polycarbonate polyol 15 and / or the second polyester polyol 15 (if the ionic liquid contains a reactive functional group reactive with an isocyanate group, the reactive functional group of the ionic liquid), (if the cyclic multidentate ligand contains a reactive functional group reactive with an isocyanate group, the reactive functional group of the cyclic multidentate ligand), and the isocyanate groups of the polyisocyanate 16 are reacted.

[0102] In this way, the dielectric layer-forming mixture is cured to form a network structure via urethane bonds, and a dielectric layer having a phase-separated structure of the urethane elastomer according to the present disclosure is obtained. The obtained dielectric layer has a domain containing a polyether structure derived from the first urethane prepolymer and a domain containing a first polycarbonate polyol and / or a first polyester polyol, and The polymer has a matrix-domain structure in which the first polycarbonate polyol and / or the second polyester polyol are dispersed in a matrix containing a urethane elastomer having a polycarbonate and / or polyester structure derived from the second polycarbonate polyol and / or the second polyester polyol.

[0103] Furthermore, the domains may be mainly composed of a polyether structure, and the interior of the domains may be substantially free of cross-linked structures. In other words, the domains may be present in a substantially liquid state in the matrix. This allows the domains in the dielectric layer according to the present disclosure to have a low elastic modulus.

[0104] Furthermore, the domains are not simply liquid portions confined within the matrix, but are chemically bonded to the matrix via urethane bonds at their boundaries, so that the recovery of the domains from deformation when the load applied to the dielectric layer is removed can be linked to the recovery of the matrix from deformation.

[0105] That is, a substantially liquid domain that does not substantially have a cross-linked structure therein has difficulty recovering autonomously from deformation even when a load is applied to the dielectric layer and the domain is deformed. However, in the dielectric layer according to the present disclosure, the domain is chemically bonded (urethane bonded) to the matrix at the boundary between the domain and the matrix, and therefore the domain can recover from deformation together with the recovery of the matrix. This makes it easier to achieve stable deformation (deformation amount) and excellent recovery from the deformation even when the dielectric layer is repeatedly subjected to loading and unloading.

[0106] From the viewpoint of achieving a high dielectric constant, it is preferable that the ionic liquid and the cyclic multidentate ligand are unevenly distributed in a matrix having urethane bonds. Therefore, it is preferable to disperse the ionic liquid and the cyclic multidentate ligand after step B(ii) as described above. In step B(ii), the interface between the matrix and the domain is firmly formed via a chemical bond (urethane bond). This prevents the ionic liquid and the cyclic multidentate ligand from penetrating the domain, thereby realizing a state in which the ionic liquid and the cyclic multidentate ligand are unevenly distributed in the matrix. Alternatively, the ionic liquid and the cyclic multidentate ligand can be dispersed well in the matrix by using a second polycarbonate polyol and / or a second polyester polyol in which the ionic liquid and the cyclic multidentate ligand have been dispersed in advance in step B(ii) and omitting step B(iii).

[0107] The above steps B(i) to B(iv) are steps for stably and uniformly dispersing the polyether polyol in the polycarbonate polyol and / or polyester polyol when the compatibility between the polycarbonate polyol and / or polyester polyol used as the matrix and the polyether polyol used as the domain is low. That is, the first urethane prepolymer is reacted with the first polycarbonate polyol and / or the first polyester polyol to form the second urethane prepolymer.

[0108] This makes it possible to obtain a dispersion in which the polyether structural segments derived from the first urethane prepolymer 11 are stably and uniformly dispersed in the second polycarbonate polyol and / or the second polyester polyol, which facilitates the production of a dielectric layer 19 in which domains 18 with high circularity and small, micrometer-order sizes with a relatively uniform size distribution are dispersed in a matrix 17.

[0109] Another method for mixing materials with low compatibility is to mix and disperse them with high shear force. However, this method applies high shear force to the domains, which can distort the domain shape and reduce the circularity, and the sizes of the domains can also become non-uniform. In addition, the dispersion state is unstable, and the domains tend to aggregate in a relatively short time. Furthermore, the incompatibility of the polycarbonate polyol and / or polyester polyol with the polyether polyol is not ensured, and the phase separation between the matrix and domains of the resulting urethane elastomer becomes unclear. This unclear phase separation also affects the mechanical properties, making it difficult to obtain the dielectric layer according to the present disclosure that is flexible and has excellent recovery from deformation.

[0110] The ratio of the polyether polyol and polycarbonate polyol and / or polyester polyol used is not particularly limited, as long as the droplets 14 can be dispersed in the second polycarbonate polyol and / or second polyester polyol 15 to form distinct domains. For example, the ratio of polyether polyol to the total of polycarbonate polyol and polyester polyol is preferably 15:85 to 50:50, more preferably 20:80 to 45:55, by mass. Note that oxygen derived from the ether bond in the polyether polyol can also electrically interact with the cation of the ionic liquid with its lone electron pair, thereby reducing the molecular mobility of the ionic liquid. Therefore, the greater the ratio of polyether polyol, the greater the relative permittivity.

[0111] The polyisocyanate 16 having at least two isocyanate groups used in step B(iv) can be the same as the polyisocyanates exemplified above as the raw material for the first urethane prepolymer. These polyisocyanates may be used alone or in combination of two or more. Among the polyisocyanates exemplified above, the polyisocyanate used in step B(iv) preferably includes polyisocyanates having at least three isocyanate groups, such as polyisocyanate trimer compounds (isocyanurates) or polymer compounds, allophanate polyisocyanates, and biuret polyisocyanates, from the viewpoint of increasing the elastic modulus of the matrix.

[0112] More preferably, at least one selected from the group consisting of a trimer compound (isocyanurate) of pentamethylene diisocyanate, a trimer compound (isocyanurate) of hexamethylene diisocyanate, and a polymeric compound (polymeric MDI) of diphenylmethane diisocyanate can be used. These compounds may be used alone or in combination.

[0113] Among the above, polymeric MDI is preferred. Polymeric MDI is a mixture of monomeric MDI and high molecular weight polyisocyanate, and is represented by the following formula (A): n in formula (A) is preferably 0 or more and 4 or less.

[0114] Commercially available polymeric MDI may be used, and examples thereof include Millionate MR series (manufactured by Tosoh Corporation) such as Millionate MR200 (trade name).

[0115] [ka]

[0116] As the polyisocyanate 16 having at least two isocyanate groups, it is preferable to use a polyisocyanate having at least three isocyanate groups, such as polymeric MDI, in combination with a bifunctional isocyanate having two isocyanate groups. That is, the polyisocyanate preferably contains a bifunctional isocyanate and a polyisocyanate having at least three isocyanate groups. This combination allows for control of the crosslink density, which is preferable from the viewpoint of achieving both low hardness and low compression set.

[0117] The amounts of the polyisocyanate having at least three isocyanate groups and the bifunctional isocyanate having two isocyanate groups are not particularly limited. The ratio of the bifunctional isocyanate to the polyisocyanate having at least three isocyanate groups when mixed into the dispersion in step B(iv) is preferably 3:1 to 1:10, more preferably 1:1 to 1:6. The amount of polyisocyanate per 100 parts by mass of the dispersion in step B(iv) is also not particularly limited, and may be, for example, 1 to 12 parts by mass or 3 to 10 parts by mass.

[0118] In the method for producing a dielectric layer in which the urethane elastomer has a phase-separated structure, a chain extender (a polyfunctional low-molecular-weight polyol) may be used as needed. As the chain extender, the same chain extenders as those described above can be used.

[0119] If necessary, additives such as conductive agents, pigments, plasticizers, waterproofing agents, antioxidants, ultraviolet absorbers, and light stabilizers may also be used in combination.

[0120] <Average circularity of domain> Furthermore, when observing three 50 μm square observation areas on the cross section of the dielectric layer, the average circularity of the domains is preferably 0.60 to 1.00, more preferably 0.80 to 1.00, and even more preferably 0.90 to 1.00. When the average circularity of the domain is within the above range, when the domain recovers from deformation, anisotropy in the direction in which the shape of the domain recovers is unlikely to occur. As a result, after recovery from deformation, wrinkles, distortions, etc. caused by the anisotropy of deformation recovery are unlikely to occur, and the dielectric layer can be made more isotropic in recovery from deformation.

[0121] The average circularity of the domain can be adjusted, for example, by the speed at which the material is injected into the mold. When the injection speed is reduced, the shear force applied to the material also decreases, and it can be heat-cured while maintaining a high circularity.

[0122] <Parameter indicating the viscoelastic term> Furthermore, in the dielectric layer, it is preferable that the elastic modulus of the domain is designed to be lower than the elastic modulus of the matrix. Specifically, in the viscoelastic image obtained by a scanning probe microscope of a cross-section where the matrix and the domain are exposed, the parameter indicating the viscoelastic term of the domain is defined as parameter A, and the parameter indicating the viscoelastic term of the matrix is defined as parameter B. At this time, it is preferable that parameters A and B satisfy A < B.

[0123] The difference in the relative elastic modulus between the matrix and the domain in the dielectric layer can be measured by observing the thinned dielectric layer with a scanning probe microscope (SPM / AFM). As the scanning probe microscope, "S-Image" (trade name) manufactured by Hitachi High-Technologies Corporation can be used. Examples of the apparatus for thinning include a sharp razor, a microtome, a focused ion beam method (FIB), etc. Among the above-mentioned apparatuses, an ultramicrotome capable of preparing an ultrathin section can be particularly preferably used. A total of 3 sections are prepared, a 50 μm square observation region is selected, and the viscoelastic image is observed in a total of 3 observation regions.

[0124] The measurement mode of the viscoelastic image by SPM is the micro viscoelastic dynamic force mode (Viscoelastic Dynamic Force Mode (VE-DFM)) and The cantilever used is a silicon microcantilever for DFM ("SI-DF3" (product name), manufactured by Hitachi High-Tech Science Corporation, spring constant = 1.9 N / m). The scanning frequency is set to 0.5 Hz.

[0125] VE-DFM (microviscoelastic DFM) is a mode that simultaneously obtains surface topography images and measures the viscoelastic distribution by controlling the distance between the probe and the sample to maintain a constant cantilever vibration amplitude while the cantilever is resonating. In VE-DFM, the sample is subjected to minute vibrations in the Z direction, and a periodic force is applied to image the viscoelastic distribution from the cantilever deflection amplitude. If the sample is hard, the cantilever amplitude increases due to the small sample deformation. If the sample is soft, the cantilever amplitude decreases due to the induced sample deformation vibration. The obtained amplitude, converted into mV displacement, is a parameter that indicates the viscoelasticity term. Therefore, parameters A and B are indicators of the relationship between the domain hardness and the matrix hardness present in a single observation sample. In VF-DFM, the cantilever amplitude is output in voltage, so parameters A and B are expressed in mV. The larger the value, the higher the elasticity.

[0126] After obtaining a viscoelastic image, parameters indicating the viscoelastic term are determined for 10 points each for the matrix and domain in each observation region, and their arithmetic mean values ​​are taken as parameter A indicating the viscoelastic term for the domain and parameter B indicating the viscoelastic term for the matrix. The measurement procedure is described below.

[0127] The ratio (A / B) of parameter A (mV) to parameter B (mV) is preferably 0.65 or less, more preferably 0.60 or less, more preferably 0.50 or less, even more preferably 0.45 or less, and particularly preferably 0.40 or less. The smaller A / B, the greater the difference in viscoelasticity between the matrix and the domain, making it easier to achieve both hardness and recovery from deformation. There is no particular restriction on the lower limit of A / B, but the smaller the ratio, the more preferable. Specifically, it is, for example, 0.10. Preferred ranges for A / B are, for example, 0.10 to 0.65, 0.10 to 0.60, 0.10 to 0.50, particularly 0.10 to 0.45, and further 0.10 to 0.40.

[0128] The parameters A and B can be adjusted, for example, by the elastic modulus of the domain and the matrix. The elastic modulus of the matrix can be adjusted, for example, by using polystyrene as a raw material for forming the matrix. It can be increased by increasing the crosslink density of the matrix using a reisocyanate trimer or polymer compound. Regarding the domain elastic modulus, for example, increasing the molecular weight of the polyether polyol used as the raw material for domain formation decreases the crosslink density of the domain, and therefore the elastic modulus.

[0129] <Micro-rubber hardness of the dielectric layer> The micro rubber hardness of the dielectric layer at a temperature of 23° C. is, for example, 15 to 60 degrees, preferably 20 to 50 degrees, and more preferably 20 to 35 degrees. When the micro rubber hardness is in this range, the dielectric layer can flexibly deform in response to external forces such as compression and tension. The micro rubber hardness can be adjusted by the elastic modulus of the matrix, the ratio of the matrix to the domain, etc. Specifically, for example, increasing the elastic modulus of the matrix and decreasing the ratio (volume) of the domain to the matrix act to increase the micro rubber hardness.

[0130] The micro rubber hardness is measured at a temperature of 23°C by using a micro rubber hardness meter (product name: MD-1capa; manufactured by Kobunshi Keiki Co., Ltd.; indenter: Type A (indenter shape: cylindrical, diameter 0.16 mm, height 0.5 mm, pressure leg dimensions: outer diameter 4 mm, inner diameter 1.5 mm); measurement mode: peak hold mode) on the surface of the dielectric layer.

[0131] <Recovery from deformation> In an indentation test using a nanoindenter at a temperature of 23°C for the dielectric layer, a Vickers indenter is placed in contact with the outer surface of the dielectric layer, and the Vickers indenter is pressed into the elastic layer at a loading rate of 10 mN / 30 seconds. The 10 mN load is maintained for 60 seconds, and then the load is released. The strain 5 seconds after unloading is preferably 1.00 μm or less. The strain 5 seconds after unloading is more preferably 0.55 μm or less, more preferably 0.50 μm or less, and even more preferably 0.40 μm or less. The lower limit of the strain 5 seconds after unloading is not particularly limited, but is typically 0.00 μm or more, may be 0.05 μm or more, or may be 0.10 μm or more. For example, preferred values ​​include 0.00 to 1.00 μm, 0.00 to 0.55 μm, 0.00 to 0.50 μm, and 0.00 to 0.40 μm.

[0132] By keeping the strain 5 seconds after unloading when measured under the above conditions within the above range, when the dielectric layer is used as a sensor, for example, the speed at which the compressed and deformed dielectric layer recovers from the deformation when the load is unloaded is increased, improving the responsiveness of the sensor.

[0133] As mentioned above, in urethane elastomers, the matrix and domains are thought to be chemically bonded by urethane bonds at the boundaries between them. Therefore, when the load applied to the dielectric layer is removed, the recovery of the domains from deformation is thought to be linked to the recovery of the matrix from deformation. This is thought to result in extremely high recovery from deformation, allowing the strain 5 seconds after removal to be within the above range.

[0134] The strain after 5 seconds of unloading can be adjusted, for example, by adjusting the elastic modulus of the matrix, assuming that the matrix and domains are chemically bonded. Specifically, the elastic modulus of the matrix can be increased by using a polyisocyanate trimer or polymer compound as at least one of the raw materials for the urethane elastomer to increase the crosslink density of the urethane elastomer matrix.

[0135] The strain value 5 seconds after unloading is the value obtained by an indentation test using a microhardness tester (nanoindenter). The measurement temperature is 23°C. A square pyramidal Vickers indenter with a facing angle of 136° is used. The measurement method involves contacting the Vickers indenter with the outer surface of the dielectric layer, pressing the Vickers indenter at a rate of 10 mN / 30 seconds, and maintaining a load of 10 mN for 60 seconds. The load is then removed (unloaded) at a rate of 10 mN / 1 second, and the strain of the dielectric layer is measured 5 seconds after unloading.

[0136] <Transducer> At least one aspect of the present disclosure provides a transducer that includes the above-described dielectric layer and is capable of converting mechanical energy into electrical energy and / or electrical energy into mechanical energy. That is, the present disclosure relates to, for example, a transducer that can convert mechanical energy into electrical energy, a transducer that can convert electrical energy into mechanical energy, and a transducer that can convert electrical energy into mechanical energy and vice versa. The transducer comprises at least two electrodes and the dielectric layer sandwiched between the electrodes. The electrodes may be connected to wiring for conducting electricity to a power source or a control element. The transducer may also have a layered structure in which the dielectric layers and the electrodes are alternately stacked.

[0137] 3 shows an example of a transducer according to the present disclosure. The transducer 2 has a dielectric layer 21 according to the present disclosure and a pair of electrodes 22 that sandwich the dielectric layer 21. The use of the transducer is not particularly limited, but it can be used as, for example, a sensor, an actuator, or a power generation element.

[0138] When the transducer is used as a sensor, the amount of deformation can be obtained by measuring the change in capacitance due to compression or expansion of the transducer 2 using the electric circuit device 3. When the transducer is used as an actuator, a driving force can be induced in the dielectric layer 21 by applying a potential difference between a pair of electrodes 22 using the electric circuit device 3. When the transducer is used as a power generating element, it is possible to obtain electrical energy accompanying the deformation of the transducer using a known method, for example, as described in Non-Patent Document 1.

[0139] The thickness of the dielectric layer 21 may be determined appropriately depending on the application of the dielectric layer 21. For example, when the dielectric layer 21 is used as a sensor, a thinner thickness is preferable from the viewpoints of high capacity and high resolution. However, since the dielectric layer according to the present disclosure has a high relative dielectric constant and can maintain high capacity and high resolution even when the dielectric layer is thick, the thickness of the dielectric layer is preferably 100 μm or more and 3 mm or less. Furthermore, when the dielectric layer 21 is used as an actuator, a thinner thickness is also preferable from the viewpoints of miniaturization, low-voltage driving, and large displacement. In consideration of resistance to dielectric breakdown, the thickness of the dielectric layer is preferably 1 μm or more and 1000 μm or less.

[0140] Electrode materials can be any conventional conductive material, including conductive carbon powders such as carbon black, carbon nanotubes, graphite, and graphene; metal powders such as silver, gold, copper, nickel, rhodium, palladium, chromium, titanium, platinum, iron, and alloys thereof; metal colloids such as colloidal silver; charge-transfer complexes such as tetrathiafulvalene / tetracyanoquinodimethane; and conductive polymers such as polypyrrole and polythiophene. Materials with flexibility that can accommodate the expansion and contraction of the dielectric layer are preferred. Examples of such electrode materials include composites composed of the aforementioned conductive materials and binders. Examples include composites in which conductive fillers are dispersed in acrylic, silicone, urethane, or styrene-based elastomer materials, silicone grease, etc., and aqueous dispersions of poly(3,4-ethylenedioxythiophene) / poly(4-styrenesulfonic acid) (PEDOT / PSS) appropriately containing organic solvents, resins, crosslinkers, etc.

[0141] The method for manufacturing the transducer according to the present disclosure is not particularly limited. Examples of methods include spraying the electrode material onto the layer, laminating the electrode material and the dielectric layer, impregnating the dielectric layer with the electrode material, and applying or printing the electrode material onto the dielectric layer.

[0142] By using the dielectric layer of the present disclosure, which has both high dielectric properties and flexibility, as the dielectric layer of the transducer, in sensor applications, a sensor with excellent capacity, high resolution, and miniaturization can be provided. Furthermore, in actuator applications, an actuator with excellent features such as increased deformation, increased output, high efficiency, drive stability, and low-voltage drive can be realized. Similarly, when the transducer is used as a power generation element, an element with excellent features such as high efficiency, high output, miniaturization, and improved power generation can be provided. [Example]

[0143] Examples of the present disclosure will be described below, but the present disclosure is not limited to these examples.

[0144] Example 1 (Preparation of mixture for forming dielectric layer) Polycarbonate diol (product name: Kuraray Polyol C-2090, Kuraray Co., Ltd.) 86.8 parts by mass of 1,4-diazabicyclo[2.2.2]octane-2-methanol (trade name: RZETA, manufactured by Tosoh Corporation) as a curing catalyst and 500 ppm of 1,4-diazabicyclo[2.2.2]octane-2-methanol (trade name: RZETA, manufactured by Tosoh Corporation) were added, and the mixture was preheated to a temperature of 100°C, and then stirred for 2 minutes in a planetary vacuum degassing mixer at a speed of 800 rpm and a revolution speed of 1600 rpm (Step A(i)). In the following examples and comparative examples, the amount of the curing catalyst is expressed in ppm by mass based on the mass of the mixture for forming the dielectric layer excluding the curing catalyst.

[0145] This is 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl 2.0 parts by mass of 18-crown-6-ether (trade name: CIL-612, manufactured by Nippon Carlit Co., Ltd.) and 1.3 parts by mass of 18-crown-6-ether (manufactured by Tokyo Chemical Industry Co., Ltd.) were added, and the mixture was preheated to a temperature of 100°C, and then stirred for 2 minutes in a rotary-revolving vacuum degassing mixer at a speed of 800 rpm and a revolution speed of 1600 rpm (Step A(ii)).

[0146] To this mixture, 4.3 parts by mass of xylylene diisocyanate (manufactured by Tokyo Chemical Industry Co., Ltd., hereinafter sometimes referred to as "XDI") and polyisocyanate (trade name: Millionate MR-200, manufactured by Tosoh Corporation, hereinafter sometimes referred to as "MR-200") were added. 6.9 parts by mass of the mixture was added and stirred for 2 minutes in a rotary-revolving vacuum degassing mixer at a rotation speed of 800 rpm and a revolution speed of 1600 rpm to obtain a mixture for forming a dielectric layer (Step A(iii)).

[0147] (Creation of dielectric layer) The dielectric layer-forming mixture was poured into a mold spaced 1 mm apart over 10 seconds, and then heated at 130°C for 2 hours to cure. The cured product was then demolded from the mold and aged at 80°C for 3 days to obtain a sheet-shaped dielectric layer measuring 5 cm square and 1 mm thick (step A(iii)). The obtained dielectric layer was evaluated as follows.

[0148] <Evaluation> [Evaluation 1: Review and analysis of the matrix and domain] A cryo-cutting system (product name: EM FC6, manufactured by Leica Microsystems) and The induced fragments were extracted using a microtome (product name: EM UC6, manufactured by Leica Microsystems). Ultrathin sections (500 μm × 500 μm × 5 μm) were prepared from the dielectric layer at three locations: the center of the dielectric layer and two locations far away from it.

[0149] Mapping measurements were performed on the prepared sections using an infrared microscope and imaging system (product names: Spectrum400 (analysis device) and Spotlight400 (scanning device), manufactured by PerkinElmer) to create mapping images. Measurements were performed using an ATR imaging accessory with a pixel size of 1.56 μm and a resolution of 16 cm. -1 The mapping measurement was performed under the conditions of a field of view of 300 μm × 300 μm and a scan speed of 1.0 cm / s. The mapping image is an image of the magnitude of the integrated value of the infrared absorption spectrum for each pixel.

[0150] From the obtained mapping image, the presence of a matrix mapped as a continuous phase and domains mapped as a discontinuous phase is confirmed. Furthermore, from the infrared absorption spectrum of the matrix in the mapping image, the structure contained in the matrix is ​​confirmed. In Example 1, it was confirmed that the matrix contained a structure corresponding to polycarbonate urethane.

[0151] [Evaluation 2: Evaluation of relative permittivity] A sample of the dielectric layer was cut to a size of 1.5 cm x 1.5 cm and clamped between a four-terminal sample holder (SH2-Z type, manufactured by Toyo Corporation) with a 10 mm diameter lower electrode and a 20 mm diameter upper electrode, both fitted with a guard electrode. The upper electrode was lowered until it contacted the dielectric layer and then pressed in 5 μm further from the contact point. Using an impedance analyzer (1260A, manufactured by Solartron) and a dielectric interface (1296A, manufactured by Solartron), an AC voltage of 0.1 Vpp was applied at room temperature, sweeping frequencies from 0.01 Hz to 1 MHz, to measure the relative permittivity ε' at a frequency of 1 kHz. The arithmetic average of three samples was used.

[0152] [Evaluation 3: Measurement of micro rubber hardness] The microhardness of the dielectric layer was measured using a microhardness tester (product name: MD-1capa, manufactured by Kobunshi Keiki Co., Ltd.). The dielectric layer was left in an environment at 23°C for at least 24 hours, and measurements were taken using a measuring device placed in the same environment. A Type A indenter (indenter shape: height 0.50 mm, diameter 0.16 mm, cylindrical; pressure leg dimensions: outer diameter 4 mm, inner diameter 1.5 mm) was used, and the measurement mode was peak hold mode. The microhardness was measured at three locations: the center of the dielectric layer and two locations sufficiently distant from it. The microhardness was measured once at each measurement location at 23°C, and the arithmetic average of the three measurement locations was used.

[0153] [Evaluation 4: Measurement of deformation recovery] The deformation recovery of the dielectric layer was evaluated by an indentation test using a nanoindenter (product name: HM2000, manufactured by Fisher Instruments Inc.) at a temperature of 23°C. For the measurement, the dielectric layer was left in an environment at a temperature of 23°C for 24 hours or more, and the measurement was performed using a measuring device placed in the same environment. Measurements were taken at three locations: the center of the dielectric layer and two locations far enough away from it. In the indentation test, a Vickers indenter was placed in contact with the outer surface of the dielectric layer, and the Vickers indenter (square pyramidal shape, facing angle 136°) was pressed in at a loading rate of 10 mN / 30 seconds, and the 10 mN load was maintained for 60 seconds. The load was then removed at a rate of 10 mN / second, and the strain was measured once at each measurement location 5 seconds after unloading was completed, and the arithmetic average of the three measurement locations was used.

[0154] <Examples 2 to 14> A dielectric layer was produced in the same manner as in Example 1, except that a mixture for forming a dielectric layer was prepared using the materials shown in Table 5 in the amounts shown in Table 5. The obtained dielectric layer was evaluated in the same manner as in Example 1. The details of the materials in Table 5 are shown in Tables 1 to 4. The same applies to the following examples.

[0155] Example 15 (Preparation of mixture for forming dielectric layer) Polypropylene glycol (trade name: Uniol D-4000, manufactured by NOF Corporation) 2 6.1 parts by mass of the resulting mixture, 2.4 parts by mass of xylylene diisocyanate (manufactured by Tokyo Chemical Industry Co., Ltd.), and 500 ppm of 1,4-diazabicyclo[2.2.2]octane-2-methanol (trade name: RZETA, manufactured by Tosoh Corporation) as a curing catalyst were added to an internal mixer, and the mixture was stirred for 4 hours in an internal mixer adjusted to 100°C, thereby synthesizing a first urethane prepolymer (step B(i)).

[0156] To this, polycarbonate diol (product name: Kuraray Polyol C-2090, manufactured by Kuraray Co., Ltd.) was added. 61.0 parts by mass of a polycarbonate diol (manufactured by Kuraray Co., Ltd.) was mixed in. The mixture was then stirred for an additional 2 hours in a sealed mixer adjusted to 100°C to synthesize a second urethane prepolymer (Step B(i)), and a dispersion in which droplets containing at least a portion of the second urethane prepolymer were dispersed in the polycarbonate diol was obtained (Step B(ii)).

[0157] This dispersion was treated with 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl) 2.0 parts by mass of 18-crown-6-ether (trade name: CIL-612, manufactured by Nippon Carlit Co., Ltd.) and 1.4 parts by mass of 18-crown-6-ether (manufactured by Tokyo Chemical Industry Co., Ltd.) were added, and the mixture was preheated to a temperature of 100°C. After that, the mixture was stirred for 2 minutes in a rotary vacuum degassing mixer at a speed of 800 rpm and a revolution speed of 1600 rpm to obtain a second dispersion (step B(iii)).

[0158] Further, 1.2 parts by mass of xylylene diisocyanate (manufactured by Tokyo Chemical Industry Co., Ltd.) and polyisocyanate (trade name: Millionate MR-200, Tosoh The mixture was stirred for 2 minutes in a rotary and revolutionary vacuum degassing mixer at a rotation speed of 800 rpm and a revolution speed of 1600 rpm to obtain a mixture for forming a dielectric layer (step B(iv)).

[0159] (Creation of dielectric layer) The dielectric layer-forming mixture was poured into a mold spaced 1 mm apart over 10 seconds, and then heated at 130°C for 2 hours to cure. The cured product was then demolded from the mold and aged at 80°C for 3 days to obtain a sheet-shaped dielectric layer measuring 5 cm square and 1 mm thick (step B(iv)). The obtained dielectric layer was evaluated according to the above-mentioned evaluations 1 to 4, as well as the following evaluations.

[0160] [Evaluation 5: Evaluation of parameters representing viscoelastic terms] Ultrathin sections were prepared in the same manner as in Evaluation 1. A total of three sections were prepared, and a 50 μm square observation area was placed in the center of each section. Viscoelastic images were observed in a total of three observation areas. Viscoelastic images were measured in a total of three observation areas using a scanning probe microscope (product name: S-Image, manufactured by SII Nano Technology Inc.). The viscoelastic image was measured in VE-DFM mode. The cantilever used was "SI-DF3" (product name, manufactured by Hitachi High-Tech Science Corporation, spring constant = 1.9 N / m). The scanning frequency was 0.5 Hz. From the obtained viscoelastic images, parameters indicating the viscoelastic term in each observation region were calculated for 10 points each for the matrix and domain, and parameter A (mV) indicating the viscoelastic term of the domain and parameter B (mV) indicating the viscoelastic term of the matrix were obtained from the arithmetic mean values. The exposure of the domains and the matrix in the cross section was confirmed by SPM viscoelasticity imaging.

[0161] [Evaluation 6: Evaluation of domain area ratio] Each of the three viscoelastic images obtained in Evaluation 5 was converted into a 256-level grayscale image using image processing software (product name: ImageProPlus, manufactured by MediaCybernetics), and then binarized to obtain a binary image for analysis. The threshold value for binarization was determined from the luminance distribution of the monochrome image based on Otsu's algorithm described in Non-Patent Document 2.

[0162] The area of ​​the domains was calculated from the obtained binarized images using the counting function of the image processing software. However, among the domains determined to be domains by the counting function, domains with a cross-sectional area of ​​less than 0.05% of the 50 μm square observation area were considered noise and removed from the data. The area corresponding to the matrix was calculated by subtracting the obtained area from the total area of ​​the observation area. From these areas, the area ratio [domain area / (matrix area + domain area) × 100 (%)] was calculated.

[0163] [Rating 7: Average circularity of domains] From the noise-removed binary image obtained in Evaluation 6, the average circularity of the domains was calculated using the counting function of the image software.

[0164] <Examples 16 to 31> A dielectric layer was produced in the same manner as in Example 15, except that a mixture for forming a dielectric layer was prepared using the materials shown in Table 5 in the amounts shown in Table 5. The obtained dielectric layer was evaluated in the same manner as in Example 1. The details of the materials in Table 5 are shown in Tables 1 to 4. The same applies to the following examples.

[0165] Example 32 A dielectric layer was produced in the same manner as in Example 15, except that the materials shown in Table 5 were used in the amounts shown in Table 5 to prepare a mixture for forming a dielectric layer, and that the mixture for forming a dielectric layer was injected into the mold for 5 seconds. The obtained dielectric layer was evaluated in the same manner as in Example 1.

[0166] [Table 1] Mn indicates the number average molecular weight.

[0167] [Table 2]

[0168] [Table 3]

[0169] [Table 4]

[0170] [Table 5]

[0171] <Comparative Example 1> Polycarbonate diol (product name: Kuraray Polyol C-2090, Kuraray Co., Ltd.) 86.8 parts by mass of 1,4-diazabicyclo[2.2.2]octane-2-methanol (trade name: RZETA, manufactured by Tosoh Corporation) as a curing catalyst and 500 ppm of 1,4-diazabicyclo[2.2.2]octane-2-methanol (trade name: RZETA, manufactured by Tosoh Corporation) were added as a curing catalyst, and the mixture was preheated to a temperature of 100°C, and then stirred for 2 minutes in a planetary vacuum degassing mixer at a speed of 800 rpm and a revolution speed of 1600 rpm. This is 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl 2.0 parts by mass of )imide (trade name: CIL-612, manufactured by Nippon Carlit Co., Ltd.) was added, and the mixture was preheated to a temperature of 100°C, followed by stirring for 2 minutes in a rotary vacuum degassing mixer at a speed of 800 rpm and a revolution speed of 1600 rpm.

[0172] To this mixture, 4.3 parts by mass of xylylene diisocyanate (manufactured by Tokyo Chemical Industry Co., Ltd.) and 6 parts by mass of polyisocyanate (trade name: Millionate MR-200, manufactured by Tosoh Corporation) were added. 0.9 parts by mass was added and stirred for 2 minutes in a rotary vacuum degassing mixer at a rotation speed of 800 rpm and a revolution speed of 1600 rpm. The resulting mixture was injected into a mold spaced 1 mm apart over 10 seconds, and then heated at 130°C for 2 hours to cure. The cured product was then removed from the mold and aged at 80°C for 3 days to obtain a sheet-shaped dielectric layer measuring 5 cm square and 1 mm thick. The resulting dielectric layer was evaluated in the same manner as in Example 1.

[0173] <Comparative Example 2> Polycarbonate diol (product name: Kuraray Polyol C-2090, Kuraray Co., Ltd.) 86.8 parts by mass of 1,4-diazabicyclo[2.2.2]octane-2-methanol (trade name: RZETA, manufactured by Tosoh Corporation) as a curing catalyst and 500 ppm of 1,4-diazabicyclo[2.2.2]octane-2-methanol (trade name: RZETA, manufactured by Tosoh Corporation) were added as a curing catalyst, and the mixture was preheated to a temperature of 100°C, and then stirred for 2 minutes in a planetary vacuum degassing mixer at a speed of 800 rpm and a revolution speed of 1600 rpm. To this was added 1.3 parts by mass of 18-crown 6-ether (Tokyo Chemical Industry Co., Ltd.). After preheating to a temperature of 100°C, the mixture was stirred for 2 minutes using a rotary-revolving vacuum degassing mixer at a speed of 800 rpm and a revolution speed of 1600 rpm.

[0174] To this mixture, 4.3 parts by mass of xylylene diisocyanate (manufactured by Tokyo Chemical Industry Co., Ltd.) and 6 parts by mass of polyisocyanate (trade name: Millionate MR-200, manufactured by Tosoh Corporation) were added. 0.9 parts by mass was added and stirred for 2 minutes in a rotary vacuum degassing mixer at a rotation speed of 800 rpm and a revolution speed of 1600 rpm. The resulting mixture was injected into a mold spaced 1 mm apart over 10 seconds, and then heated at 130°C for 2 hours to cure. The cured product was then removed from the mold and aged at 80°C for 3 days to obtain a sheet-shaped dielectric layer measuring 5 cm square and 1 mm thick. The resulting dielectric layer was evaluated in the same manner as in Example 1.

[0175] <Comparative Example 3> 89.2 parts by mass of a vinyl-terminated polydimethylsiloxane (trade name: DMS-V31, manufactured by Azmax Corporation) and 0.50 parts by mass of a 2-propanol solution of 1 (mMol / L) chloroplatinic acid (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a curing catalyst were added, and the mixture was stirred for 2 minutes using a planetary vacuum degassing mixer at a speed of 800 rpm and a revolution speed of 1600 rpm. This is 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl 2.0 parts by mass of 18-crown 6-ether (trade name: CIL-612, manufactured by Nippon Carlit Co., Ltd.) and 1.3 parts by mass of 18-crown 6-ether (manufactured by Tokyo Chemical Industry Co., Ltd.) were added and the mixture was heated to a temperature of 10 After preheating to 0°C, the mixture was stirred for 2 minutes using a rotary-revolving vacuum degassing mixer at a speed of 800 rpm and a revolution speed of 1600 rpm.

[0176] To this mixture, 8.83 parts by mass of polyhydrogenmethylsiloxane (trade name: HMS-151, manufactured by Azmax Corporation) was added, and the mixture was stirred for 2 minutes using a rotary-revolving vacuum degassing mixer at a speed of 800 rpm and a revolution speed of 1600 rpm. The resulting mixture was poured into a mold spaced 1 mm apart over 10 seconds, and then heated at 130°C for 2 hours to cure. The cured product was then removed from the mold and aged at 200°C for another 2 hours to produce a sheet 5 cm square and 1 mm thick. The dielectric layer of the silicone molded article was evaluated in the same manner as in Example 1.

[0177] The evaluation results of Examples 1 to 32 and Comparative Examples 1 to 3 are shown in Tables 6-1 to 6-3.

[0178] [Table 6-1]

[0179] [Table 6-2]

[0180] [Table 6-3] In Tables 6-1 to 6-3, M represents the matrix and D represents the domain.

[0181] The dielectric layers according to Examples 1 to 14 had a high relative dielectric constant at a frequency of 1 kHz, and also maintained the flexibility of an elastomer because they did not contain a hard filler such as barium titanate.

[0182] The dielectric layers of Examples 15 to 32 had multiple domains dispersed in a matrix containing a urethane elastomer, and parameter B, which indicates the viscoelasticity of the matrix, was greater than parameter A, which indicates the viscoelasticity of the domains. As a result, they were more flexible than the dielectric layers of Examples 1 to 14 and had excellent recovery properties against deformation. The dielectric constant at a frequency of 1 kHz was also higher than that of the dielectric layers of Examples 1 to 14 due to the polyether-derived structure of the domains.

[0183] On the other hand, it is believed that the molecular mobility of the ionic liquid in the dielectric layer of Comparative Example 1 was reduced due to interaction with the urethane bond. However, because the dielectric layer of Comparative Example 1 did not contain a cyclic multidentate ligand, the distance between the ion pairs in the ionic liquid was not large enough, which is thought to have resulted in a low relative permittivity at a frequency of 1 kHz. Furthermore, since the dielectric layer according to Comparative Example 2 did not contain an ionic liquid, polarization between ion pairs of the ionic liquid did not occur in the first place, and the relative dielectric constant at a frequency of 1 kHz was also low.

[0184] The dielectric layer of the silicone molded article in Comparative Example 3 contains both an ionic liquid and a cyclic multidentate ligand, but it is believed that the absence of a urethane bond prevents the molecular mobility of the ionic liquid from being reduced. As a result, the cyclic multidentate ligand cannot coordinate with the cation of the ionic liquid, and the dielectric constant at a frequency of 1 kHz is also low. The above evaluation results demonstrate that the dielectric layer according to the present disclosure has both high dielectric properties and flexibility, and is suitable as a dielectric layer for transducers and the like.

[0185] The present disclosure relates to the following configurations. (Configuration 1) A transducer capable of converting mechanical energy into electrical energy and / or electrical energy into mechanical energy, the transducer having a dielectric layer; The dielectric layer has a relative dielectric constant of 8.0 or more at a frequency of 1 kHz, The dielectric layer satisfies any one of the following (i) to (vi): A transducer characterized by: (i) the dielectric layer comprises a urethane elastomer, an ionic liquid, and a cyclic multidentate ligand; (ii) the dielectric layer comprises a urethane elastomer, a cyclic multidentate ligand, and an anion, and the urethane elastomer has a cation structure in its molecule; (iii) the dielectric layer contains a urethane elastomer, a cyclic multidentate ligand, and a cation, and the urethane elastomer has an anionic structure in its molecule; (iv) the dielectric layer comprises a urethane elastomer and an ionic liquid, and the urethane elastomer has a cyclic multidentate ligand structure in its molecule; (v) the dielectric layer comprises a urethane elastomer and an anion, and the urethane elastomer has a cyclic multidentate ligand structure and a cation structure in its molecule; (vi) The dielectric layer contains a urethane elastomer and a cation, and the urethane elastomer has a cyclic multidentate ligand structure and an anion structure in the molecule. (Configuration 2) 2. The transducer of claim 1, wherein the dielectric layer satisfies (i). (Configuration 3) 2. The transducer of claim 1, wherein the dielectric layer satisfies (ii). (Configuration 4) 2. The transducer of claim 1, wherein the dielectric layer satisfies (iii). (Configuration 5) 2. The transducer of claim 1, wherein the dielectric layer satisfies (iv). (Configuration 6) 2. The transducer of claim 1, wherein the dielectric layer satisfies (v). (Configuration 7) 2. The transducer of claim 1, wherein the dielectric layer satisfies (vi). (Configuration 8) 8. The transducer according to any one of configurations 1 to 7, wherein the relative dielectric constant is 10.0 or more. (Configuration 9) 9. The transducer according to any one of configurations 1 to 8, wherein the relative dielectric constant is 20.0 or more. (Configuration 10) 10. The transducer according to any one of configurations 1 to 9, wherein the urethane elastomer includes at least one selected from the group consisting of polycarbonate urethane and polyester urethane. (Configuration 11) the urethane elastomer has a matrix and domains dispersed in the matrix; the matrix comprises at least one selected from the group consisting of polycarbonate urethane and polyester urethane; The domain has a structure represented by the following formula (1): The transducer according to any one of configurations 1 to 10. TIFF2025165857000015.tif9112 (In formula (1), R 1 represents an alkylene group having 3 to 5 carbon atoms. (Configuration 12) the urethane elastomer has a matrix and domains dispersed in the matrix; The relationship between a parameter A indicating the viscoelasticity term of the domain and a parameter B indicating the viscoelasticity term of the matrix, which are measured in a viscoelastic image of a cross section in which the domain and the matrix are exposed, by a scanning probe microscope, is <Bである、 12. The transducer according to any one of configurations 1 to 11. (Configuration 13) The dielectric layer has a micro rubber hardness of 20 to 50 degrees at a temperature of 23°C, In an indentation test using a nanoindenter at a temperature of 23°C of the dielectric layer, a Vickers indenter is brought into contact with the outer surface of the dielectric layer, the Vickers indenter is pressed at a loading rate of 10 mN / 30 seconds, the load of 10 mN is maintained for 60 seconds, and then the load is released. When this is done, the strain 5 seconds after the load is released is 1.00 μm or less. 13. The transducer according to any one of configurations 1 to 12. (Configuration 14) 14. The transducer according to any one of aspects 1 to 13, wherein the cyclic multidentate ligand has a structure represented by the following formula (2): TIFF2025165857000016.tif26153 (In formula (2), n is an integer of 4 to 8, and R 2 represents a substituted or unsubstituted ethylene group or a substituted or unsubstituted phenylene group. (Configuration 15) 14. The transducer according to any one of aspects 1 to 13, wherein the cyclic multidentate ligand has a structure represented by the following formula (3): TIFF2025165857000017.tif55153 (In formula (3), n is an integer of 4 to 6, and R3 represents a hydrogen atom or an organic group. (Configuration 16) 14. The transducer according to any one of aspects 1 to 13, wherein the cyclic multidentate ligand has a structure represented by the following formula (4): TIFF2025165857000018.tif85153 (In formula (4), R 4 and R 5 each independently represents a hydrogen atom or an organic group. (Configuration 17) 17. The transducer according to any one of configurations 1 to 16, wherein the transducer is a sensor, an actuator, or a power generating element.

Claims

1. A transducer capable of converting mechanical energy into electrical energy and / or electrical energy into mechanical energy, the transducer having a dielectric layer; the dielectric layer has a relative dielectric constant of 8.0 or more at a frequency of 1 kHz; The dielectric layer satisfies any one of the following (i) to (vi): A transducer characterized by: (i) the dielectric layer comprises a urethane elastomer, an ionic liquid, and a cyclic multidentate ligand; (ii) the dielectric layer comprises a urethane elastomer, a cyclic multidentate ligand, and an anion, and the urethane elastomer has a cation structure in its molecule; (iii) the dielectric layer contains a urethane elastomer, a cyclic multidentate ligand, and a cation, and the urethane elastomer has an anionic structure in its molecule; (iv) the dielectric layer comprises a urethane elastomer and an ionic liquid, and the urethane elastomer has a cyclic multidentate ligand structure in its molecule; (v) the dielectric layer comprises a urethane elastomer and an anion, and the urethane elastomer has a cyclic multidentate ligand structure and a cation structure in its molecule; (vi) The dielectric layer comprises a urethane elastomer and a cation, and the urethane elastomer has a cyclic multidentate ligand structure and an anion structure in the molecule.

2. The transducer of claim 1 , wherein the dielectric layer satisfies (i).

3. The transducer of claim 1 , wherein the dielectric layer satisfies (ii).

4. The transducer of claim 1 , wherein the dielectric layer satisfies (iii).

5. The transducer of claim 1 , wherein the dielectric layer satisfies (iv).

6. The transducer of claim 1 , wherein the dielectric layer satisfies (v).

7. The transducer of claim 1 , wherein the dielectric layer satisfies (vi).

8. The transducer of claim 1 , wherein the dielectric constant is 10.0 or greater.

9. The transducer of claim 1 , wherein the dielectric constant is 20.0 or greater.

10. The transducer of claim 1 , wherein the urethane elastomer comprises at least one selected from the group consisting of polycarbonate urethane and polyester urethane.

11. the urethane elastomer has a matrix and domains dispersed in the matrix; the matrix comprises at least one selected from the group consisting of polycarbonate urethane and polyester urethane; The domain has a structure represented by the following formula (1): The transducer of claim 1 . (In formula (1), R １ represents an alkylene group having 3 to 5 carbon atoms.

12. the urethane elastomer has a matrix and domains dispersed in the matrix; a parameter A indicating a viscoelastic term of the domain and a parameter B indicating a viscoelastic term of the matrix, the parameter A being measured in a viscoelastic image of a cross section in which the domain and the matrix are exposed by a scanning probe microscope, has a relationship of A<B; 12. A transducer according to claim 1 or 11.

13. The dielectric layer has a micro rubber hardness of 20 to 50 degrees at a temperature of 23°C, In an indentation test using a nanoindenter at a temperature of 23°C of the dielectric layer, a Vickers indenter is brought into contact with the outer surface of the dielectric layer, the Vickers indenter is pressed at a loading rate of 10 mN / 30 seconds, the load of 10 mN is maintained for 60 seconds, and then the load is released. After that, the strain after 5 seconds of release is 1.00 μm or less.

12. A transducer according to claim 1 or 11.

14. The transducer according to claim 1 or 11, wherein the cyclic multidentate ligand has a structure represented by the following formula (2): (In formula (2), n is an integer of 4 to 8, and R ２ represents a substituted or unsubstituted ethylene group or a substituted or unsubstituted phenylene group.

15. The transducer according to claim 1 or 11, wherein the cyclic multidentate ligand has a structure represented by the following formula (3): (In formula (3), n is an integer of 4 to 6, and R ３ represents a hydrogen atom or an organic group.

16. The transducer according to claim 1 or 11, wherein the cyclic multidentate ligand has a structure represented by the following formula (4): (In formula (4), R ４ and R ５ each independently represents a hydrogen atom or an organic group.

17. The transducer of claim 1 or 11, wherein the transducer is a sensor, an actuator, or a power generating element.

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