JP5206367B2 - Organic piezoelectric materials containing urea compounds - Google Patents

Description

  The present invention relates to a cyclic urea or cyclic thiourea compound, and more particularly to an organic piezoelectric material containing the compound.

  Conventionally, acoustic devices such as microphones and speaker diaphragms, various thermal sensors, pressure sensors, measuring devices such as infrared detectors, ultrasonic probe, vibration sensors that detect mutations such as genes and proteins with high sensitivity, etc. Organic piezoelectric materials having piezoelectricity and pyroelectricity that can be used to convert heat and mechanical stimulation into electrical energy are known.

As the pyroelectric material, a so-called inorganic material in which a single crystal such as quartz, LiNbO ₃ , LiTaO ₃ , KNbO ₃ , a thin film such as ZnO or AlN, or a sintered body such as Pb (Zr, Ti) O ₃ is subjected to polarization treatment. Piezoelectric materials are widely used. These inorganic piezoelectric materials have characteristics such as high elastic stiffness, high mechanical loss coefficient, high density and high dielectric constant.

  On the other hand, organic piezoelectric materials such as polyvinylidene fluoride (hereinafter abbreviated as “PVDF”) and polycyanovinylidene (hereinafter abbreviated as “PVDCN”) have also been developed (for example, see Patent Document 1). This organic piezoelectric material is excellent in workability such as thin film and large area, can be made in any shape and form, and has features such as low elastic modulus and low dielectric constant. It has the feature that enables high-sensitivity detection when the use of is considered. On the other hand, organic piezoelectric materials have low heat resistance and lose their pyroelectric properties at high temperatures, and the physical properties such as elastic stiffness are greatly reduced.

  In contrast to these limitations, polyurea resin compositions composed of urea bonds have a large dipole moment of urea bonds and are excellent in temperature characteristics as resins. Therefore, various studies have been made as organic piezoelectric materials. . For example, there is a so-called vapor deposition polymerization method in which a polyurea film is formed by simultaneously evaporating a diisocyanate compound such as 4,4'-diphenylmethane diisocyanate (MDI) and a diamine compound such as 4,4'-diaminodiphenylmethane (MDA). It is disclosed (for example, see Patent Documents 2 and 3). However, since the polyurea resin composition prepared by the vapor deposition polymerization method described in these documents has a non-uniform molecular weight of the oligomer or high molecular weight product to be produced, when the molecular weight is increased while performing polarization treatment, In this state, the polyurea resin composition is formed. For this reason, the dipole moment of the urea bond cannot be fully utilized, and further improvement has been demanded as an organic piezoelectric material.

As one of the means for increasing the orientation of the urea group-containing compound, a method of aligning the urea group in a certain direction by orienting the molecule with a ring structure of the urea group can be considered. Reports have been limited (for example, Patent Document 4), and no example of attention paid to piezoelectricity has been reported so far.
JP-A-6-216422 JP-A-2-284485 Japanese Patent Laid-Open No. 5-31399 JP-A-9-31060

  The present invention has been made in view of the above problems and circumstances, and an object of the present invention is to provide a ferroelectric cyclic urea or cyclic thiourea compound, and further, a novel that can be effectively used as an organic piezoelectric material. To provide materials.

  The above object of the present invention is achieved by the following means.

  1. An organic piezoelectric material comprising a compound represented by the following general formula (1):

[In formula, Q represents an oxygen atom or a sulfur atom. R ₁ and R ₂ represent a hydrogen atom or a substituent. Z represents a nonmetallic atom group necessary for forming a 5-membered or 6-membered ring. ]
2. 2. The organic piezoelectric material as described in 1 above, wherein Q in the general formula (1) is a sulfur atom.

  3. 3. The organic piezoelectric material as described in 1 or 2 above, wherein the nonmetallic atom group Z necessary for forming a 5-membered or 6-membered ring in the general formula (1) consists only of a carbon atom or a nitrogen atom .

  4). 3. The organic piezoelectric material according to 1 or 2, wherein the general formula (1) is represented by the following general formula (2) or (3).

[In General Formula (2), R ₂₁ , R ₂₂ , A ₂₁ , A ₂₂ represent a hydrogen atom or a substituent, and at least two adjacent groups of R ₂₁ , A ₂₁ , A ₂₂ form a condensed ring structure. To do. Q ₂₁ and Q ₂₂ represent an oxygen atom or a sulfur atom. ]

[In General Formula (3), R ₃₁ , A ₃₁ , A ₃₂ , A ₃₃ and A ₃₄ represent a hydrogen atom or a substituent, and at least two groups adjacent to each other form a condensed ring structure. X ₁ and X ₂ represent a carbon atom or a nitrogen atom, and X ₁ and X ₂ are bonded by a single bond or a double bond. Q ₃₁ and Q ₃₂ represent an oxygen atom or a sulfur atom. ]
5. 1. The film comprising a film containing the compound represented by the general formula (1), the general formula (2) or the general formula (3) and a thermoplastic resin, a thermosetting resin or a photocurable resin. The organic piezoelectric material of any one of -4.

  6). Any one of the items 1 to 4 above, comprising a film containing a compound represented by the general formula (1), the general formula (2) or the general formula (3) and a ferroelectric polymer. The organic piezoelectric material described.

  The present invention has been made in view of the above-described problems and circumstances, and the purpose thereof is to use a cyclic urea compound or a cyclic thiourea compound, which is excellent in piezoelectric characteristics for converting heat and mechanical stimulation into electrical energy, in particular, An object of the present invention is to provide an organic piezoelectric material having high orientation and being thermally stable.

  Next, the best mode for carrying out the present invention will be described, but the present invention is not limited thereto.

  First, the compound represented by the general formula (1) will be described.

<Compound represented by formula (1)>
In the general formula (1), Q represents an oxygen atom or a sulfur atom. Q is preferably a sulfur atom.

R ₁ and R ₂ represent a hydrogen atom or a substituent.

Specific examples of the substituent represented by R ₁ and R ₂ include alkyl groups having 1 to 25 carbon atoms (methyl group, ethyl group, propyl group, isopropyl group, tert-butyl group, pentyl group, hexyl group, cyclohexyl group). Group), halogenated alkyl group (trifluoromethyl group, perfluorooctyl group, etc.), cycloalkyl group (cyclohexyl group, cyclopentyl group etc.), alkynyl group (propargyl group etc.), glycidyl group, acrylate group, methacrylate group, Aromatic groups (such as phenyl groups), heterocyclic groups (pyridyl group, thiazolyl group, oxazolyl group, imidazolyl group, furyl group, pyrrolyl group, pyrazinyl group, pyrimidinyl group, pyridazinyl group, selenazolyl group, sriphoranyl group, piperidinyl group, pyrazolyl group Group, tetrazolyl group, etc.), halogen atom (chlorine source) , Bromine atom, iodine atom, fluorine atom, etc.), alkoxy group (methoxy group, ethoxy group, propyloxy group, pentyloxy group, cyclopentyloxy group, hexyloxy group, cyclohexyloxy group, etc.), aryloxy group (phenoxy group, etc.) ), Alkoxycarbonyl group (methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, etc.), aryloxycarbonyl group (phenyloxycarbonyl group, etc.), sulfonamide group (methanesulfonamide group, ethanesulfonamide group, butane) Sulfonamide group, hexanesulfonamide group, cyclohexanesulfonamide group, benzenesulfonamide group, etc.), sulfamoyl group (aminosulfonyl group, methylaminosulfonyl group, dimethylaminosulfonyl group, butylamino) Nosulfonyl group, hexylaminosulfonyl group, cyclohexylaminosulfonyl group, phenylaminosulfonyl group, 2-pyridylaminosulfonyl group, etc.), urethane group (methylureido group, ethylureido group, pentylureido group, cyclohexylureido group, phenylureido group, 2-pyridylureido group, etc.), acyl group (acetyl group, propionyl group, butanoyl group, hexanoyl group, cyclohexanoyl group, benzoyl group, pyridinoyl group, etc.), carbamoyl group (aminocarbonyl group, methylaminocarbonyl group, dimethylamino) Carbonyl group, propylaminocarbonyl group, pentylaminocarbonyl group, cyclohexylaminocarbonyl group, phenylaminocarbonyl group, 2-pyridylaminocarbonyl group, etc.), amide group (acetate) Amide group, propionamide group, butanamide group, hexaneamide group, benzamide group, etc.), sulfonyl group (methylsulfonyl group, ethylsulfonyl group, butylsulfonyl group, cyclohexylsulfonyl group, phenylsulfonyl group, 2-pyridylsulfonyl group, etc.), Amino group (amino group, ethylamino group, dimethylamino group, butylamino group, cyclopentylamino group, anilino group, 2-pyridylamino group, etc.), cyano group, nitro group, sulfo group, carboxyl group, hydroxyl group, oxamoyl group, etc. Can be mentioned. Further, these groups may be further substituted with these groups.

The substituent represented by R ₁ and R ₂ is preferably a hydrogen atom or an alkyl group having 1 to 10 carbon atoms.

  Z represents a nonmetallic atom group necessary for forming a 5-membered or 6-membered ring. Specific examples of the 5-membered or 6-membered ring represented by Z include the following (Z-1) to (Z-12).

(Z-1) from the (Z-12), Q, R 1 and _{R 2} are the same Q, _{R 1} and _{R 2} in the general formula (1). B ₁ , B ₂ and B ₃ represent a hydrogen atom or a substituent, and specific examples of the substituent include the examples given as specific examples of the substituent represented by R ₁ and R ₂ in the general formula (1). Can be mentioned. B ₁ and B ₂ , and B ₂ and B ₃ may form a condensed ring structure. The substituent represented by B ₁ , B ₂ and B ₃ is preferably an alkyl group having 1 to 20 carbon atoms or an alkoxy group. In (Z-1), (Z-2), and (Z-5) to (Z-11), a combination of a broken line and a solid line indicates a single bond or a double bond.

In addition, B ₁ , B ₂ or B ₃ is the monovalent substituent, and at least one of B ₁ , B ₂ or B ₃ is a ring element and carbonyl bonded thereto, carbonyl, thiocarbonyl, etc. It may be an oxygen or sulfur atom forming the structure.

L ₁ and L ₂ represent a substituent, and specific examples of the substituent represented by L ₁ and L ₂ are the same as the specific examples of the substituent represented by R ₁ and R ₂ . Moreover, when there are a plurality of L ₁ and L ₂ , adjacent L ₁ and L ₂ may form a condensed ring structure. The substituents represented by L ₁ and L ₂ are preferably an alkoxy group, an alkyl group, and an aromatic group.

n1 and n2 represents an integer of 0 to 4, when n1 and n2 is 2 or more, _{L 1} and _{L 2} may be the same or different.

  Z is preferably (Z-3), (Z-4), (Z-6), (Z-8), (Z-9), or (Z-10), more preferably (Z -3), (Z-4), (Z-8), and (Z-10).

In the general formula (2), R ₂₁ and R ₂₂ represent a hydrogen atom or a substituent. Specific examples of the substituent represented by R ₂₁ and R ₂₂ include the examples given as examples of R ₁ and R _{2 in} the general formula (1). The substituent represented by R ₂₁ and R ₂₂ is preferably an alkyl group having 1 to 20 carbon atoms.

A ₂₁ and A ₂₂ represent a hydrogen atom or a substituent, and at least two groups adjacent to each other among R ₂₁ , A ₂₁ and A ₂₂ form a condensed ring structure. The substituents represented by R ₂₁ , A ₂₁ , and A ₂₂ are preferably an alkyl group, an alkoxy group, and an aromatic group, and more preferably an alkoxy group and an aromatic group.

Q ₂₁ and Q ₂₂ represent an oxygen atom or a sulfur atom.

In the general formula (3), R ₃₁ represents a hydrogen atom or a substituent. The substituent represented by R ₃₁ is preferably an alkyl group having 1 to 20 carbon atoms.

A ₃₁ , A ₃₂ , A ₃₃ and A ₃₄ represent substituents, and at least two groups adjacent to each other form a condensed ring structure. The substituents represented by A ₃₁ , A ₃₂ , A ₃₃ and A ₃₄ are preferably an alkyl group, an alkoxy group and an aromatic group, and more preferably an alkoxy group and an aromatic group.

Q ₃₁ and Q ₃₂ represent an oxygen atom or a sulfur atom. Preferably it is a sulfur atom.

X ₁ and X ₂ represent a carbon atom or a nitrogen atom.

  Specific examples of the compounds represented by the general formula (1), the general formula (2), and the general formula (3) are shown below, but the present invention is not limited thereto.

  The compound represented by the general formula (1) can be synthesized by a known method. For example, it can be synthesized with reference to the methods described in JP-B-6-067910, JP-B-7-103109, JP-A-9-31060, JP-A-2004-115402, and the like.

  Synthesis examples of typical compounds are shown below.

  Synthesis Example 1 Synthesis of Compound 5

  10.0 g of benzoin was dissolved in 50 ml of acetic acid, and 4.0 g of thiourea was added dropwise over 15 minutes. After stirring at room temperature for 3 hours, 200 ml of water was injected, and ethyl acetate was further added for extraction. The obtained organic layer was further washed with 100 ml of water three times, and then the organic layer was dried over sodium sulfate. The solvent was distilled off under reduced pressure, and the remaining assembled product was purified by silica gel column chromatography (heptane: ethyl acetate = 10: 1) to obtain 10.2 g of Intermediate A (yield 86%).

  Subsequently, 80 ml of acetone was added and dissolved in 10.2 g of the intermediate A. A solution of 8.2 g of potassium carbonate and 10 ml of water was added, 10.8 g of iododecane was further added, and the mixture was stirred at 50 ° C. for 8 hours.

150 ml of water was added to the reaction solution, and extracted with 200 ml of methyl ethyl ketone. The organic layer was dried over sodium sulfate, and the solvent was distilled off under reduced pressure. The obtained solid was purified by silica gel column chromatography (heptane: ethyl acetate = 20: 1) to obtain 21.3 g (yield 80%) of compound 5.
¹ H-NMR spectrum (CDCl ₃ , ppm): 0.86 (t, 6H), 1.26-1.30 (m, 28H), 1.62-1.65 (m, 4H), 4.36 (T, 4H), 7.29 (m, 2H), 7.45-7.47 (m, 4H), 7.82 (d, 4H)
IR spectrum (ATR method, cm ⁻¹ ): 1642, 1425, 1250, 780, 752, 695
Mass spectrum (API method, m / e (relative intensity)): 533 ((45) MH ⁺ ), 391 ((20) MH ⁺ -141)
Synthesis Example 2 Synthesis of Compound 13

  9.7 g of 8,11-bis (hexyloxy) perylene was dissolved in 120 ml of THF (tetrahydrofuran) and cooled to 0 ° C. A solution of 2.4 g of O-methylchloroformate thioester in 20 ml of THF was added dropwise over 30 minutes. The mixture was stirred at room temperature for 1 hour and then heated at 40 ° C. for 2 hours. The precipitated solid was collected by filtration and washed with methylene chloride to obtain 7.3 g of Intermediate B (yield 70%).

To 7.3 g of the intermediate B, 100 ml of acetone and 4.6 g of potassium carbonate were added and dissolved. 7.1 g of 1-iodohexane was added and stirred at room temperature for 5 hours. Ethyl acetate was added to the solution for extraction, and the resulting organic layer was dried over sodium sulfate. After the solvent was distilled off under reduced pressure, the residue was purified by silica gel column chromatography (heptane: ethyl acetate = 5: 1). 5.0g of compound 13 was obtained (yield 52%).
¹ H-NMR spectrum (CDCl ₃ , ppm): 0.86-0.87 (m, 9H), 1.29-1.49 (m, 28H), 1.75 (m, 4H), 4.16 (T, 4H), 4.47 (t, 4H), 6.68 (m, 2H), 6.89 (s, 2H), 7.43 (s, 2H), 7.75 (s, 2H)
IR spectrum (ATR method, cm ⁻¹ ): 1640, 1425, 785, 705
Mass spectrum (API method, m / e (relative intensity)): 695 ((65) MH ⁺ )
Synthesis Example 3 Synthesis of Compound 39

  10.77 g of 2-octylurazole, 23.5 g of benzyltriphenylphosphine peroxysulfate, and 6.5 g of aluminum chloride were stirred at room temperature for 10 minutes. Extraction was performed by adding 100 ml of methylene chloride, and the resulting organic layer was dried over sodium sulfate. The solvent was distilled off under reduced pressure and then purified by distillation to obtain 8.9 g of Intermediate C (yield 85%).

8.9 g of Intermediate C was dissolved in 80 ml of methylene chloride, 27.5 g of 1,2-bis (dodecyloxy) -7,8-dihydrobenzoperylene and 3.36 g of pyridine were added and cooled to 10 ° C. Bromine 8.2g was dripped here, and it stirred at 10 degreeC for 3 hours. The mixture was extracted with 50 ml of methylene chloride, and the organic layer was washed 3 times with 100 ml of water, and then the obtained organic layer was dried over sodium sulfate. The solvent was distilled off under reduced pressure to obtain 14.2 g of the assembled product. Purification was performed by silica gel chromatography (heptane: ethyl acetate = 10: 1) to obtain 10.9 g of Compound 39 (yield 30%).
¹ H-NMR spectrum (CDCl ₃ , ppm): 0.85-0.87 (m, 9H), 1.24-1.31 (m, 46H), 1.63 (m, 2H), 1.76 (M, 4H), 4.17 (t, 4H), 4.41 (t, 2H), 7.39-7.42 (m, 8H)
IR spectrum (ATR method, cm ⁻¹ ): 1645, 1423, 782, 754, 700
Mass spectrum (API method, m / e (relative intensity)): 855 ((70) MH ⁺ )
<Organic piezoelectric material>
The organic piezoelectric material of the present invention forms an organic piezoelectric film by forming a film containing the compound represented by the general formula (1) or by subjecting the film to further polarization treatment. can do.

  In the organic piezoelectric film, when stress is applied to the piezoelectric film, charges of opposite signs appear in proportion to both ends of the piezoelectric film, that is, an electric polarization phenomenon occurs. It has the property (piezoelectric performance) that a distortion proportional to that occurs when it is put into (applying an electric field). In particular, in an organic piezoelectric film made of the organic piezoelectric material of the present invention, a large piezoelectric effect is generated by polarization due to orientation freezing of molecular dipole moments.

  On the other hand, when energy (heat) is applied to the piezoelectric film, the magnitude of spontaneous polarization in the piezoelectric film changes accordingly. At this time, the surface charge existing on the surface of the piezoelectric film so as to neutralize the spontaneous polarization cannot respond to the energy change as quickly as the spontaneous polarization. There is a charge corresponding to the change in spontaneous polarization. The generation of electricity accompanying this energy change is referred to as pyroelectricity. In particular, in the case of an organic piezoelectric film made of the organic piezoelectric material of the present invention, a large pyroelectric performance is generated by polarization due to the orientation freezing of the dipole moment.

(Method of forming organic piezoelectric film)
The organic piezoelectric film is preferably formed by coating. Examples of the coating method include spin coating, solvent casting, melt casting, melt press, roll coating, flow coating, printing, dip coating, and bar coating.

  In the present invention, preferably, the compound represented by the general formula (1) is preferably applied or formed in a temperature range in which a liquid crystal phase is exhibited, and the formed film is further subjected to polarization treatment described later. Also good.

  When the compound represented by the general formula (1) is formed on the organic piezoelectric film, an arbitrary polymer compound may be further mixed to improve the film formability. As the polymer compound to be mixed, specifically, a thermoplastic resin, a thermosetting resin, or a photocurable resin having a number average molecular weight of 1500 or more is used.

  As the thermoplastic resin, any resin having a number average molecular weight of 1500 or more, preferably 1500 to 100,000 can be used without particular limitation. If the number average molecular weight of the thermoplastic resin is less than 1500, the glass transition temperature is too low, and the mechanical stability of the organic piezoelectric film may be lowered.

  Specific examples of the thermoplastic resin suitably used in the present invention include polyvinyl chloride, polyvinyl bromide, polyvinyl fluoride, vinyl chloride-vinyl acetate copolymer, vinyl chloride-ethylene copolymer, vinyl chloride-propylene. Copolymer, vinyl chloride-vinylidene chloride copolymer, vinyl chloride-butadiene copolymer, vinyl chloride-acrylic acid ester copolymer, vinyl chloride-acrylonitrile copolymer, vinyl chloride-styrene-acrylonitrile terpolymer , Vinyl chloride-vinylidene chloride-vinyl acetate copolymer, polyvinylidene chloride, polytetrafluoroethylene, polytetrafluorochloroethylene, polyvinylidene fluoride, and other halogenated vinyl polymers or copolymers; polyvinyl alcohol, polyallyl alcohol, Polyvinyl ether, polyallyl A Polymers or copolymers of unsaturated alcohols or ethers such as ruthenium; Polymers or copolymers of unsaturated carboxylic acids such as acrylic acid or methacrylic acid; Polyvinyl esters such as polyvinyl acetate, Polyallyl such as polyphthalic acid Polymers or copolymers of unsaturated residues in alcohol residues such as esters; acid residues or acid residues such as polyacrylic acid ester, polymethacrylic acid ester, maleic acid ester or fumaric acid ester polymer Or copolymers having unsaturated bonds in the alcohol residue; polymers or copolymers of acrylonitrile or methacrylonitrile; unsaturated nitriles such as polymers or copolymers of polycyanide vinylidene, malononitrile or fumaronitrile Polymer or copolymer; polystyrene Polymers of aromatic vinyl compounds such as poly-α-methylstyrene, poly-p-methylstyrene, styrene-α-methylstyrene copolymer, styrene-p-methylstyrene copolymer, polyvinylbenzene, and polyhalogenated styrene Or copolymer; polymer or copolymer of a heterocyclic compound such as polyvinyl pyridine, poly-N-vinyl pyrrolidine, poly-N-vinyl pyrrolidone; polyester condensate such as polycarbonate, nylon 6, nylon 6, 6, etc. Polyamide condensates; polymers or copolymers containing maleic anhydride, fumaric anhydride and imidized products thereof; polyamideimide, polyetherimide, polyimide, polyphenylene oxide, polyphenylene sulfide, polysulfone, polyethersulfone, polyarylate, etc. Heat resistant organic Etc. The. Of these, polycarbonate, polystyrene, polyacrylate, polymethacrylate, nylon and the like are preferably used.

  As a thermosetting resin, various things including what is marketed, such as an epoxy adhesive and an acrylic adhesive, can be used. As the photo-curable resin, various kinds of resins including those that are commercially available such as an adhesive that is cured by visible light, UV light, electron beam, or the like can be used. These non-liquid crystalline polymer substances may be appropriately selected from the manufacturing method of the organic piezoelectric film and the required durability.

  Specific examples of the heat or photocurable resin suitably used in the present invention include, for example, an epoxy adhesive, an acrylic adhesive, an unsaturated polyester adhesive, a polyurethane adhesive, a hot melt adhesive, and an elastomer type. Mention may be made of adhesives.

  As an example of the epoxy adhesive, a bisphenol A type is preferable as the main agent. A main agent in which the bisphenol A portion is a bisphenol compound as shown below can also be used.

  Examples of polyurethane adhesives include methylene bis (p-phenylene diisocyanate), tolylene diisocyanate, hexamethylene diisocyanate, 1-chlorophenyl diisocyanate, 1,5-naphthylene diisocyanate, thiodipropyl diisocyanate, ethylbenzene-α- as an isocyanate component. Examples include 2-di-isocyanate, 4,4,4-triphenylmethane triisocyanate, and the components that react with them include ethylene glycol, propylene glycol, triethylene glycol, tetraethylene glycol, glycerol, hexanetriol, and xylylene diene. All, lauric acid monoglyceride, stearic acid monoglyceride, oleic acid monoglyceride, polyethylene glycol, polypro Glycol, polyesters, polyamides, and the like.

  The mixing amount of the resin compound is 10 to 80% by mass, preferably 20 to 80% by mass with respect to the compound represented by the general formula (1). If the amount of the resin compound is less than 10% by mass, the film-forming property may be deteriorated and the mechanical strength may be insufficient. On the other hand, when it exceeds 80 mass%, unnecessary light scattering may occur, and the performance of the organic piezoelectric film may be deteriorated.

  Further, the compound represented by the general formula (1) may be used by mixing with other ferroelectric polymers. Specifically, polyvinylidene fluoride (PVDF), vinylidene fluoride / ethylene trifluoride copolymer P (VDF / TrFE), vinylidene fluoride / tetrafluoroethylene copolymer P (VDF / TeFE), cyanide To vinylidene / vinyl acetate copolymer P (VDCN / VA), vinyl fluoride / ethylene trifluoride copolymer P (VF / TrFE), and vinyl fluoride / ethylene trifluoride copolymer P (VF / TrFE) Copolymer added with vinylidene fluoride, tetrafluoroethylene, hexafluoroacetone and hexafluoropropylene as the third component, amide polymer such as nylon 7 or nylon 11, aliphatic polyurea, aliphatic polyurethane, etc. Can be used.

(Polarization treatment)
In the formed film, the bond of urea or the like may be in an arbitrary direction. In this case, it is preferable to perform polarization treatment. As a polarization processing method in the polarization processing according to the present invention, various conventionally known methods can be applied.

  For example, in the case of the corona discharge treatment method, the corona discharge treatment can be performed by using a commercially available device comprising a high voltage power source and electrodes.

  Since the discharge conditions vary depending on the equipment and processing environment, it is preferable to select the conditions as appropriate. However, the voltage of the high voltage power source is −1 to −20 kV, the current is 1 to 80 mA, and the distance between the electrodes is 1 to 10 cm. The applied voltage is preferably 0.5 to 2.0 MV / m.

  As the electrodes, needle-like electrodes, linear electrodes (wire electrodes), and mesh-like electrodes that have been conventionally used are preferable, but the invention is not limited thereto.

  In addition, since heating is performed during corona discharge, it is necessary to install a heater via an insulator under the electrode in contact with the substrate manufactured according to the present invention.

  In the present invention, when the corona discharge treatment is performed as the polarization treatment in the state where the solvent of the coating solution remains, it is sufficient to remove the volatile components of the solvent in order to avoid the danger of flammable explosion. It is necessary for safety to carry out with ventilation.

(substrate)
As the substrate, the selection of the substrate differs depending on the application and use method of the organic piezoelectric film of the present invention. It may be a plastic plate or film such as polyimide, polyamide, polyimide amide, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polymethyl methacrylate (PMMA), polycarbonate resin, cycloolefin polymer. The surface may be covered with aluminum, gold, copper, magnesium, silicon or the like. A single crystal plate or film of aluminum, gold, copper, magnesium, silicon simple substance, or rare earth halide may also be used.

  Further, a multilayer piezoelectric element may be formed on the piezoelectric element. As a method of using a multilayer for stacking piezoelectric elements, there is a method in which the organic piezoelectric film of the present invention is superposed on a ceramic piezoelectric element via an electrode. PZT is used as the ceramic piezoelectric element, but in recent years, one containing no lead has been recommended.

PZT is preferably within the range of the formula Pb (Zr _1-X Ti _X ) O ₃ (0.47 ≦ X ≦ 1). As deleading, natural or artificial quartz, lithium niobate (LiNbO ₃ ), potassium niobium tantalate [K (Ta, Nb) O ₃ ], barium titanate (BaTiO ₃ ), lithium tantalate (LiTaO ₃ ), or strontium titanate (SrTiO ₃ ). The composition of various ceramic materials can be selected as appropriate in terms of performance.

  EXAMPLES Hereinafter, although a synthesis example and an Example are given and this invention is demonstrated, this invention is not limited to these.

Example 1
<Measurement of spontaneous polarization>
The spontaneous polarization was measured for the compound represented by the general formula (1). In this measurement, a glass substrate on which 1 cm × 1 cm of ITO (Indium-Tin-Oxide) is formed is arranged so as to oppose an interval of 5 μm, and a compound represented by the general formula (1) is injected between the glass substrates. A cell was prepared, and a triangular wave voltage (amplitude ± 20 V / μm, 6 Hz cycle) was applied to the liquid crystal cell. As a result, when all the liquid crystal compounds were in the hexagonal columnar phase, the inversion peak of the liquid crystal molecules was observed, confirming that it was a ferroelectric liquid crystal. The results of this measurement are shown in Table 1 (the temperature when this spontaneous polarization was measured was 120 ° C.).

Example 2
<Evaluation of piezoelectric e characteristics and thermal stability of organic piezoelectric film>
A compound represented by the general formula (1) shown in Table 2 and a resin compound or a ferroelectric polymer are dissolved in tetrahydrofuran or dimethylformamide, and then cast on a glass plate to a thickness of about 100 μm. And dried at 100 ° C. under reduced pressure for 12 hours. After peeling this film from the glass plate, it was pressed to a thickness of about 40 μm to produce organic piezoelectric films 1 to 18. The organic piezoelectric films 1 to 18 are fixed on a hot plate, a tungsten needle is placed 1.5 cm away from the top of the organic piezoelectric film, and a voltage of 4.0 kV is applied thereto to perform polarization treatment by corona discharge. went. The temperature of the organic piezoelectric film was kept at 120 ° C. during the corona discharge treatment.

  Similarly, Comparative Organic Piezoelectric Films A to C were produced using Comparative-A, Comparative-B and Comparative-C shown in Table 3 instead of the compound represented by the general formula (1).

  With respect to the organic piezoelectric films 1 to 18 and the comparative piezoelectric films A to C created as described above, a measuring device: impedance analyzer (manufactured by Agilent, 4194A) was used to measure the room temperature (25 ° C.) and 100 using a resonance-antiresonance method. The piezoelectric e constant was evaluated in the state heated to ° C. The results are shown in Table 2. The piezoelectric e constant is shown as a relative value with respect to 100% of the value measured for the comparative organic piezoelectric film C at room temperature.

  As is clear from the results shown in Table 2, it can be seen that the piezoelectric properties of the organic piezoelectric film formed by the compound of the present invention are superior to those of the comparative example and the orientation of the polarization group is high.

Claims (6)

An organic piezoelectric material comprising a compound represented by the following general formula (1):

[In formula, Q represents an oxygen atom or a sulfur atom. R ₁ and R ₂ represent a hydrogen atom or a substituent. Z represents a nonmetallic atom group necessary for forming a 5-membered or 6-membered ring. ] The organic piezoelectric material according to claim 1, wherein Q in the general formula (1) is a sulfur atom. 3. The organic piezoelectric element according to claim 1, wherein the nonmetallic atom group Z necessary for forming a 5-membered or 6-membered ring in the general formula (1) comprises only a carbon atom or a nitrogen atom. material. The organic piezoelectric material according to claim 1 or 2, wherein the general formula (1) is represented by the following general formula (2) or (3).

[In General Formula (2), R ₂₁ , R ₂₂ , A ₂₁ , A ₂₂ represent a hydrogen atom or a substituent, and at least two adjacent groups of R ₂₁ , A ₂₁ , A ₂₂ form a condensed ring structure. To do. Q ₂₁ and Q ₂₂ represent an oxygen atom or a sulfur atom. ]

[In General Formula (3), R ₃₁ , A ₃₁ , A ₃₂ , A ₃₃ and A ₃₄ represent a hydrogen atom or a substituent, and at least two groups adjacent to each other form a condensed ring structure. X ₁ and X ₂ represent a carbon atom or a nitrogen atom, and X ₁ and X ₂ are bonded by a single bond or a double bond. Q ₃₁ and Q ₃₂ represent an oxygen atom or a sulfur atom. ] It consists of a film | membrane containing the compound represented with the said General formula (1), General formula (2), or General formula (3), and a thermoplastic resin, a thermosetting resin, or a photocurable resin. The organic piezoelectric material according to any one of 1 to 4. 5. The film according to claim 1, comprising a film containing a compound represented by the general formula (1), the general formula (2), or the general formula (3) and a ferroelectric polymer. The organic piezoelectric material described in 1.