JP2010018726A - Organic piezoelectric material, organic piezoelectric film, ultrasonic oscillator, ultrasonic probe and ultrasonic medical image diagnostic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic piezoelectric material and an organic piezoelectric film each of which is excellent in piezoelectric properties and handleability, and to provide an ultrasonic oscillator, an ultrasonic probe and an ultrasonic medical image diagnostic apparatus in each of which the organic piezoelectric material and the organic piezoelectric film are used. <P>SOLUTION: The organic piezoelectric material contains an organic polymer material having the structure shown by general formula (UP1) (wherein R<SB>1</SB>and R<SB>2</SB>are each an alkylene group, an arylene group or a heteroarylene group independently; X is an oxygen atom or a sulfur atom; R<SB>3</SB>and R<SB>4</SB>are each a hydrogen atom, an alkyl group, an aryl group or a heteroaryl group but are not hydrogen atoms simultaneously) and has ≥0.2 electromechanical coupling factor. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an organic piezoelectric material and an organic piezoelectric film excellent in piezoelectric characteristics and handleability, an ultrasonic transducer using them, an ultrasonic probe, and an ultrasonic medical diagnostic imaging apparatus.

  Ultrasonic probes are rapidly being used as non-destructive inspection devices and medical ultrasonic diagnostic devices. For example, a probe such as an ultrasonic endoscope radiates a high-frequency acoustic vibration from an ultrasonic transducer into a subject, receives the reflected ultrasonic wave by the ultrasonic transducer, and has a slight interface characteristic. A cross-sectional image inside the living body is obtained by processing different information depending on the difference.

  In recent years, harmonic imaging (Harmonic) that forms an image of the internal state of a subject by its harmonic frequency component, not by the frequency (fundamental frequency) component of the ultrasound transmitted from the ultrasound probe into the subject. Imaging technology is being researched and developed. In this harmonic imaging technique, (1) the side lobe level is smaller than the fundamental frequency component level, the S / N ratio (signal to noise ratio) is improved, and the contrast resolution is improved. Increasing the beam width narrows and the lateral resolution improves. (3) Multiple reflections are suppressed because the sound pressure is small and the fluctuation of the sound pressure is small at a short distance, and (4) It has various advantages such as a greater depth than the case where the attenuation beyond the focal point is the same as that of the fundamental wave and a high frequency is the fundamental wave, and enables highly accurate diagnosis (for example, Patent Document 1). reference).

Such an ultrasonic probe uses a piezoelectric body that generates ultrasonic waves. Conventionally, as a piezoelectric body, a so-called inorganic material in which a single crystal such as quartz, LiNbO ₃ , LiTaO ₃ , or 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 ceramics are widely used.

On the other hand, organic piezoelectric materials (also referred to as “piezoelectric polymer materials” or “polymer piezoelectric materials”) using organic polymer materials such as polyvinylidene fluoride (PVDF) and polyurea have been developed. (For example, refer to Patent Document 2). This organic piezoelectric body has greater flexibility than ceramics piezoelectric bodies, and can be easily made into any shape and form with a thin film, large area, and long length. small, hydrostatic voltage output coefficient (g _h constant) excellent sensitivity characteristics because very becomes larger, it is possible to further lower density, due to low elasticity, efficient energy propagation, having the properties and the like.

However, in the case of polyurea, the hydrogen bond of the urea group is strong, so the solubility is very poor, and the rigidity is high, so that the handleability is extremely bad. However, there was a fault limited to the vapor deposition polymerization method.
Japanese Patent Laid-Open No. 11-276478 JP-A-6-216422

  The present invention has been made in view of the above-described problems and situations, and a problem to be solved is to provide an organic piezoelectric material and an organic piezoelectric film excellent in piezoelectric characteristics and handleability. Furthermore, it is to provide an ultrasonic transducer, an ultrasonic probe, and an ultrasonic medical image diagnostic apparatus using them.

  The above-mentioned problem according to the present invention is solved by the following means.

  1. An organic piezoelectric material comprising an organic polymer material having a structure represented by the following general formula (UP1), wherein an electromechanical coupling constant is 0.2 or more.

(In the formula, R ₁ and R ₂ each independently represent an alkylene group, an arylene group or a heteroarylene group. X represents an oxygen atom or a sulfur atom. R ₃ and R ₄ each independently represent hydrogen. Represents an atom, an alkyl group, an aryl group or a heteroaryl group, except when R ₃ and R ₄ are simultaneously hydrogen atoms.)
2. 2. The organic piezoelectric material as described in 1 above, wherein the general formula (UP1) is represented by the following general formula (UP2).

(Wherein, R ₁ and R ₂ are each independently, .R ₇ representing an alkylene group, an arylene group or a heteroarylene group is a methyl group, an ethyl group, or propyl group.)
3. 3. The organic piezoelectric material as described in 1 or 2 above, wherein the organic piezoelectric material contains an organic polymer material formed using a macromonomer having a molecular weight of 400 to 10,000 as a raw material.

  4). An organic piezoelectric film formed using the organic piezoelectric material according to any one of 1 to 3 above.

  5. An ultrasonic vibrator comprising an organic piezoelectric film formed using the organic piezoelectric material according to any one of 1 to 3, wherein the organic piezoelectric film has electrodes on both sides thereof, and It is an organic piezoelectric film manufactured by polarization treatment before formation of electrodes placed on both sides of the organic piezoelectric film, after formation of electrodes only on one side, or after formation of electrodes on both sides. Sonic transducer.

  6). 6. The ultrasonic transducer according to 5, wherein the polarization process is a voltage application process or a corona discharge process.

  7). An ultrasonic probe comprising an ultrasonic transmission transducer and an ultrasonic reception transducer, comprising the organic piezoelectric film formed of the organic piezoelectric material according to any one of 1 to 3 above. An ultrasonic probe using an ultrasonic transducer as an ultrasonic receiving transducer.

  8). Ultrasound in which a means for generating an electrical signal and a plurality of transducers for receiving the electrical signal and transmitting an ultrasonic wave toward the subject and generating a reception signal corresponding to the reflected wave received from the subject are arranged In the ultrasonic medical image diagnostic apparatus, comprising: an ultrasonic probe; and an image processing unit that generates an image of the subject according to the reception signal generated by the ultrasonic probe. The ultrasonic medical diagnostic imaging apparatus according to claim 7, wherein the ultrasonic diagnostic probe is the ultrasonic probe according to 7.

  By the above means of the present invention, it is possible to provide an organic piezoelectric material and an organic piezoelectric film excellent in piezoelectric characteristics and handleability. Furthermore, an ultrasonic transducer, an ultrasonic probe, and an ultrasonic medical image diagnostic apparatus using them can be provided.

  That is, from the viewpoint of the mechanism of action, when manufacturing an organic piezoelectric film from an organic piezoelectric material, it is necessary to dissolve the organic piezoelectric material in a solvent, and then dry after casting. Because of its high hydrogen bonding properties, its solubility is very poor, and because of its high molecular rigidity, it becomes brittle after drying, poor handling, and difficult to transport in the process. There is a problem that the film is damaged and the yield is lowered, and the advantage of the organic piezoelectric material cannot be utilized.

  However, in the present invention, the molecular structure that moderately relaxes the hydrogen bonds formed in the organic polymer material can improve the solubility of the material and improve the handleability and productivity of the organic piezoelectric film. Presumed to be possible. Further, since the flexibility of the material is improved, the dipole alignment treatment essential for the piezoelectric material, that is, the polarization treatment can be effectively performed.

  Accordingly, it is possible to provide an organic piezoelectric material, an organic piezoelectric film, an ultrasonic transducer, an ultrasonic probe, and an ultrasonic medical image diagnostic apparatus that take advantage of the original characteristics.

  The organic piezoelectric material of the present invention is an organic piezoelectric material containing an organic polymer material having a structure represented by the general formula (UP1), and has an electromechanical coupling constant of 0.2 or more. . This feature is a technical feature common to the inventions according to claims 1 to 8.

  As an embodiment of the present invention, the general formula (UP1) is preferably an embodiment represented by the general formula (UP2). Moreover, it is preferable that the said organic piezoelectric material is an aspect containing the organic polymer material formed using the macromonomer whose molecular weight is 400-10,000 as a raw material.

  The organic piezoelectric material of the present invention is suitable as a material for forming an organic piezoelectric film because it has the characteristics of excellent piezoelectric characteristics and flexibility. The organic piezoelectric film can be suitably used for an ultrasonic vibrator. In the case of an ultrasonic vibrator, it is preferable to perform polarization treatment either before forming the electrodes to be installed on both sides of the organic piezoelectric film, after forming electrodes only on one side, or after forming electrodes on both sides. Moreover, it is preferable that the said polarization process is a voltage application process or a corona discharge process.

  The ultrasonic transducer according to the present invention can be suitably used as an ultrasonic receiving transducer, particularly in an ultrasonic probe including an ultrasonic transmitting transducer and an ultrasonic receiving transducer. Furthermore, this ultrasonic probe can be used for an ultrasonic medical image diagnostic apparatus. For example, means for generating an electrical signal and a plurality of transducers that receive the electrical signal and transmit an ultrasonic wave toward the subject and generate a reception signal corresponding to the reflected wave received from the subject are arranged. In the ultrasonic medical image diagnostic apparatus, comprising: an ultrasonic probe; and an image processing unit that generates an image of the subject according to the reception signal generated by the ultrasonic probe. It can be suitably used as a touch element.

  Hereinafter, the present invention, its components, and the best mode and mode for carrying out the invention will be described in detail.

(Organic polymer material constituting organic piezoelectric material)
In the organic piezoelectric material of the present invention, various organic polymer materials can be used as a constituent material. However, the organic piezoelectric material contains an organic polymer material having a structure represented by the general formula (UP1). The organic piezoelectric material has an electromechanical coupling constant of 0.2 or more. Hereinafter, an organic polymer material constituting the organic piezoelectric material will be described.

<Organic polymer material having a structure represented by the general formula (UP1)>
In the general formula (UP1), R ₁ and R ₂ each independently represents an alkylene group, an arylene group, or a heteroarylene group. X represents an oxygen atom or a sulfur atom. R ₃ and R ₄ are each independently a hydrogen atom, an alkyl group, an aryl group or a heteroaryl group, if R ₃ and R ₄ do not simultaneously hydrogen atoms is excluded.

  Examples of the alkylene group include methylene group, ethylene group, trimethylene group, tetramethylene group, propylene group, ethylethylene group, pentamethylene group, hexamethylene group, 2,2,4-trimethylhexamethylene group, heptamethylene group, Octamethylene group, nonamethylene group, decamethylene group, undecamethylene group, dodecamethylene group, cyclohexylene group (for example, 1,6-cyclohexanediyl group, etc.), cyclopentylene group (for example, 1,5-cyclopentanediyl group) Etc.).

  Examples of the arylene group include an o-phenylene group, m-phenylene group, p-phenylene group, naphthalenediyl group, anthracenediyl group, naphthacenediyl group, pyrenediyl group, naphthylnaphthalenediyl group, and biphenyldiyl group (for example, 3,3′- Biphenyldiyl group, 3,6-biphenyldiyl group, etc.), terphenyldiyl group, quaterphenyldiyl group, kinkphenyldiyl group, sexiphenyldiyl group, septiphenyldiyl group, octiphenyldiyl group, nobiphenyldiyl group Group, deciphenyldiyl group, methylenebisphenyl group, fluorenyl group, and the like.

  Examples of the heteroarylene group include a carbazole ring, a triazine ring, a triazole ring, a pyrrole ring, a pyridine ring, a pyrazine ring, a quinoxaline ring, a thiophene ring, an oxadiazole ring, a dibenzofuran ring, a dibenzothiophene ring, and an indole ring. Derived divalent groups and the like can be mentioned.

  Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a tert-butyl group, a pentyl group, a hexyl group, an octyl group, a dodecyl group, a tridecyl group, a tetradecyl group, a pentadecyl group, a cyclopentyl group, and a cyclohexyl group. Etc.

  As the aryl group, for example, phenyl group, p-chlorophenyl group, mesityl group, tolyl group, xylyl group, naphthyl group, anthryl group, azulenyl group, acenaphthenyl group, fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, biphenylyl group Etc.

  Examples of the heteroaryl group include furyl group, thienyl group, pyridyl group, pyridazyl group, pyrimidyl group, pyrazyl group, triazyl group, imidazolyl group, pyrazolyl group, thiazolyl group, benzoimidazolyl group, benzoxazolyl group, quinazolyl group, Examples thereof include a phthalazyl group.

  n is preferably 10-30.

In the present invention, the general formula (UP1) is preferably an embodiment represented by the general formula (UP2). In the general formula (UP2), R ₁ and R ₂ each independently represents an alkylene group, an arylene group, or a heteroarylene group. R ₇ is a methyl group, an ethyl group, or a propyl group. Incidentally, _{R 1} and _{R 2} have the same meanings as _{R 1} and _{R 2} in the general formula (UP1).

<< Synthesis of organic polymer materials >>
An organic polymer material having a structure represented by the general formula (UP1) includes a disubstituted amine compound having R ₁ and R ₃ and a disubstituted amine compound having R ₂ and R ₄ to a carbonyl group or thiocarbonyl. method, the 2-substituted amine compounds with R ₁ and R _3, reacting the isothiocyanate compound having an isocyanate compound or R ₂ having R ₂ is reacted with a coupling agent to introduce the group, R ₂ and R ₄ 2-substituted amine compounds with, can be synthesized by a method of reacting an isothiocyanate compound having an isocyanate compound or R ₁ having R _1.

  The starting materials are the amine compounds, isocyanate compounds, and isothiocyanate compounds substituted by the alkylene group, arylene group, heteroarylene group, alkyl group, aryl group, and heteroaryl group mentioned above.

In the case of synthesizing by a method in which a divalent amine compound having R ₁ and R ₃ and a disubstituted amine compound having R ₂ and R ₄ are reacted with a coupling agent for introducing a carbonyl group or a thiocarbonyl group, R _{1 is used.} Coupling of a compound having two disubstituted amino groups with R ₃ and R ₃ and a compound having two disubstituted amino groups with R ₂ and R ₄ , or disubstitution with R ₁ and R ₃ it may be a coupling of compounds having di-substituted amino group having an amino group and R ₂ and R ₄ one by one.

  Coupling agents that can be used are compounds capable of introducing a carbonyl group or a thiocarbonyl group, specifically phosgene, thiophosgene, 1,1'-carbonyldiimidazole, 1,1'-thiocarbonyldiimidazole, dimethyl carbonate. , Diphenyl carbonate, dimethylcarbonothioate, diphenylcarbonothioate, bis (trichloromethyl) carbonate, bis (trichloromethyl) carbonate, and the like.

  The amount of coupling agent used is preferably 1.1 to 1.5 equivalents per 1 equivalent of amine compound. More preferably, it is 1.1-1.2 equivalent.

  The reaction temperature for coupling depends on the coupling agent used, but is preferably as low as possible, -40 to 60 ° C, preferably -20 to 30 ° C, and more preferably -10 to 10 ° C. The reaction temperature may be a constant temperature from the start to the end of the reaction, or may be initially low and then increased.

On the other hand, the 2-substituted amine compounds with R ₁ and R _3, a method of reacting an isothiocyanate compound having an isocyanate compound or R ₂ having the R _2, the 2-substituted amine compounds with R ₂ and R _4, R _When reacting an isocyanate compound having ₁ or an isothiocyanate compound having R ₁ , the amine compound comprises a compound having two disubstituted amino groups having R ₁ and R ₃ , R ₂ and R ₄ A compound having two disubstituted amino groups, a compound having one disubstituted amino group having R ₁ and R ₃ and _one disubstituted amino group having R ₂ and R ₄ can be used. The isocyanate compound, diisothiocyanate compound having a diisocyanate compound or R ₂ having the R _2, diisocyanate compound having an R ₄ or diisothiocyanate compound having R ₄ can be used.

  The reaction temperature for polyaddition depends on the compound used, but is preferably as low as possible, -40 to 60 ° C, preferably -20 to 30 ° C, more preferably -10 to 10 ° C. The reaction temperature may be a constant temperature from the start to the end of the reaction, or may be initially low and then increased.

  As the solvent used for the reaction, it is necessary to use a highly polar solvent in order that the target resin composition is highly polar and the polymerization proceeds efficiently. For example, it is preferable to select a highly polar aprotic solvent such as DMF (N, N-dimethylformamide), DMAc (N, N-dimethylacetamide), DMSO (dimethylsulfoxide), NMP (N-methylpyrrolidone), As long as the reaction substrate and target compound dissolve well, aliphatic hydrocarbons such as cyclohexane, pentane and hexane, aromatic hydrocarbons such as benzene, toluene and chlorobenzene, THF (tetrahydrofuran), diethyl ether, ethylene glycol diethyl It may be a solvent such as ethers such as ether, ketones such as acetone, methyl ethyl ketone, 4-methyl-2-pentanone, esters such as methyl propionate, ethyl acetate, butyl acetate, etc. May be.

  The organic polymer material may be purified by any means, but purification by reprecipitation is preferred. The reprecipitation method is not particularly limited, but a method in which the organic polymer material is dissolved in a good solvent and then dropped into the poor solvent to be deposited is preferable.

  The “good solvent” as used herein may be any solvent as long as it dissolves the macromonomer, but is preferably a polar solvent, specifically, DMF (N, N-dimethylformamide), DMAc. Examples thereof include highly polar aprotic solvents such as (N, N-dimethylacetamide), DMSO (dimethyl sulfoxide), and NMP (N-methylpyrrolidone).

  The “poor solvent” may be any solvent as long as it does not dissolve the macromonomer, but is an aliphatic hydrocarbon such as cyclohexane, pentane or hexane, or an aromatic hydrocarbon such as benzene, toluene or chlorobenzene. And ethers such as diethyl ether and ethylene glycol diethyl ether, esters such as methyl propionate, ethyl acetate and butyl acetate, and alcohols such as methanol, ethanol and propanol.

  Specific examples of the organic polymer material are given below, but the present invention is not limited thereto.

  The content of the polymer material in the organic piezoelectric material containing the organic polymer material having the structure represented by the general formula (UP1) is 50 to 100% by mass ratio, more preferably 70 to 100%. is there.

  The use conditions are such that the polymer material that does not cause phase separation with the material to be mixed within the aforementioned mass ratio range is selected.

  An adjustment method for using an electromechanical coupling constant of 0.2 or more is that a film is produced from an organic piezoelectric material containing the polymer material, and the film is stretched, annealed, polarized, etc. It is obtained by applying. Annealing treatment and polarization treatment may be used in combination.

  In the case of a stretching process, it is desirable to stretch 2 to 5 times. Although the temperature at the time of stretching depends on the physical properties of the organic piezoelectric material, stretching at 20 to 150 ° C is preferable, and 40 to 120 ° C is more preferable.

  In the case of the annealing treatment, if the organic piezoelectric material is a material exhibiting ferroelectricity, it is necessary to carry out at a temperature equal to or lower than the Curie temperature. On the other hand, if the material does not exhibit ferroelectricity, it is necessary to carry out at a melting point or lower.

  In the case of the polarization treatment, various known methods such as direct current corona discharge treatment and alternating current application treatment can be used.

<Other organic polymer materials that can be used in combination>
In the present invention, various organic polymer materials can be used. Organic polymer materials formed from a polymerizable compound having an electron-withdrawing group having an action of increasing the amount of dipole moment of the organic polymer material. It is preferable that Since such an organic polymer material has an action of increasing the amount of dipole moment, excellent piezoelectric characteristics can be obtained when used as an organic piezoelectric material (film).

  In the present application, the “electron withdrawing group” refers to a substituent having a Hammett substituent constant (σp) of 0.10 or more as an index indicating the degree of electron withdrawing. As the value of Hammett's substituent constant σp here, Hansch, C .; It is preferable to use the values described in the report of Leo et al. (For example, J. Med. Chem. 16, 1207 (1973); ibid. 20, 304 (1977)).

  For example, the substituent or atom having a value of σp of 0.10 or more includes a halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom), carboxyl group, cyano group, nitro group, halogen-substituted alkyl group (for example, trichloro Methyl, trifluoromethyl, chloromethyl, trifluoromethylthiomethyl, trifluoromethanesulfonylmethyl, perfluorobutyl), aliphatic, aromatic or aromatic heterocyclic acyl groups (eg formyl, acetyl, benzoyl), aliphatic / aromatic Or aromatic heterocyclic sulfonyl group (for example, trifluoromethanesulfonyl, methanesulfonyl, benzenesulfonyl), carbamoyl group (for example, carbamoyl, methylcarbamoyl, phenylcarbamoyl, 2-chloro-phenylcarbamoyl), alkoxycarbonyl (For example, methoxycarbonyl, ethoxycarbonyl, diphenylmethylcarbonyl), substituted aryl groups (for example, pentachlorophenyl, pentafluorophenyl, 2,4-dimethanesulfonylphenyl, 2-trifluoromethylphenyl), aromatic heterocyclic groups (for example, 2 -Benzoxazolyl, 2-benzthiazolyl, 1-phenyl-2-benzimidazolyl, 1-tetrazolyl), azo group (eg phenylazo), ditrifluoromethylamino group, trifluoromethoxy group, alkylsulfonyloxy group (eg methanesulfonyl) Oxy), acyloxy groups (eg acetyloxy, benzoyloxy), arylsulfonyloxy groups (eg benzenesulfonyloxy), phosphoryl groups (eg dimethoxyphosphonyl, diphenylphosphoryl) ), Sulfamoyl groups (for example, N-ethylsulfamoyl, N, N-dipropylsulfamoyl, N- (2-dodecyloxyethyl) sulfamoyl, N-ethyl-N-dodecylsulfamoyl, N, N-diethyl) Sulfamoyl) and the like.

  Specific examples of the compound that can be used in the present invention include the following compounds or derivatives thereof, but are not limited thereto.

  4,4'-diaminodiphenylmethane (MDA), 4,4'-methylenebis (2-methylaniline), 4,4'-methylenebis (2,6-dimethylaniline), 4,4'-methylenebis (2-ethyl- 6-methylaniline), 4,4'-methylenebis (2,6-diethylaniline), 4,4'-methylenebis (2,6-di-t-butylaniline), 4,4'-methylenebis (2,6 -Dicyclohexylaniline), 4,4'-methylenebis (2-ethylaniline), 4,4'-methylenebis (2-tert-butylaniline), 4,4'-methylenebis (2-cyclohexylaniline), 4,4 ' -Methylenebis (3,5-dimethylaniline), 4,4'-methylenebis (2,3-dimethylaniline), 4,4'-methylenebis (2,5-dimethyl) Nilin), 2,2-bis (4-aminophenyl) hexafluoropropane, 2,2-bis (4-aminophenyl) propane, 1,1-bis (4-aminophenyl) cyclohexane, α, α-bis ( 4-aminophenyl) toluene, 4,4'-methylenebis (2-chloroaniline), 4,4'-methylenebis (2,6-dichloroaniline), 4,4'-methylenebis (2,3-dibromoaniline), 3,4'-diaminodiphenyl ether, 4,4'-diaminooctafluorodiphenyl ether, 4,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl disulfide, bis (4-aminophenyl) sulfone, bis (3-amino Phenyl) sulfone, bis (3-amino-4-hydroxyphenyl) sulfone, bis (4-amino) Phenyl) sulfoxide, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene, 2,2-bis [4 -(4-aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,5-bis (4-aminophenyl) -1,3,4-oxa Diazole, neopentyl glycol bis (4-aminophenyl) ether, 4,4'-diaminostilbene, α, α'-bis (4-aminophenyl) -1,4-diisopropylbenzene, 1,2-phenylenediamine, 1,3-phenylenediamine, 1,4-phenylenediamine, benzidine, 4,4'-diaminooctafluorobiphenyl, 3 3'-diaminobenzidine, 3,3'-dimethylbenzidine, 2,2'-bis (trifluoromethyl) benzidine, 3,3 ', 5,5'-tetramethylbenzidine, 3,3'-dihydroxybenzidine, 3 , 3'-dimethylbenzidine, 3,3'-dihydroxy-5,5'-dimethylbenzidine, 4,4 "-diamino-p-terphenyl, 1,5-diaminonaphthalene, 1,8-diaminonaphthalene, 2, 3-diaminonaphthalene, 2,6-diaminonaphthalene, 2,7-diaminonaphthalene, 3,3′-dimethylnaphthidine, 2,7-diaminocarbazole, 3,6-diaminocarbazole, 3,4-diaminobenzoic acid, 3,5-diaminobenzoic acid, 1,5-diaminopentane, 1.6-diaminohexane, 1,7-diminoheptane, 1 8-diaminooctane, 1,9-diaminononane, 1,5-dimethylhexylamine, 1,3-bis (aminomethyl) cyclohexane, 1,4-bis (aminomethyl) cyclohexane, 1-1: 4, 4'- Diaminobenzophenone, 4,4'-dimethylamino-3,3'-dichlorobenzophenone, 4,4'-diamino-5,5'-diethyl-3,3'-difluorobenzophenone, 4,4'-diamino-3, 3 ', 5,5'-tetrafluorobenzophenone, 2,2-bis (4-aminophenyl) propane, 2,2-bis (4-amino-3,5-dichlorophenyl) propane, 2,2-bis (4 -Aminophenyl) hexafluoropropane, 2,2-bis (4-amino-3-fluorophenyl) hexafluoropropane, 4,4'-diamy Nodiphenyl ether (ODA), 4,4'-diamino-3,3 ', 5,5'-tetrachlorodiphenyl ether, 4,4'-diaminodiphenyl sulfide, 4,4'-diamino-3,3'-dibromodiphenyl Sulfide, 4,4'-diaminodiphenyl disulfide, 4,4'-diamino-3,3 ', 5,5'-tetrafluorodiphenyl disulfide, bis (4-aminophenyl) sulfone, bis (4-amino-3- Chloro-5-methylphenyl) sulfone, bis (4-aminophenyl) sulfoxide, bis (4-amino-3-bromophenyl) sulfoxide, 1,1-bis (4-aminophenyl) cyclopropane, 1,1-bis (4-aminophenyl) cyclooctane, 1,1-bis (4-aminophenyl) cyclohexane, 1, -Bis (4-amino-3,5-difluorophenyl) cyclohexane, 4,4 '-(cyclohexylmethylene) dianiline, 4,4'-(cyclohexylmethylene) bis (2,6-dichloroaniline), 2,2- Diethyl bis (4-aminophenyl) malonate, diethyl 2,2-bis (4-amino-3-chlorophenyl) malonate, 4- (di-p-aminophenylmethyl) pyridine, 1- (di-p-aminophenylmethyl) ) Diamine compounds such as -1H-pyrrole, 1- (di-p-aminophenylmethyl) -1H-imidazole, 2- (di-p-aminophenylmethyl) oxazole and their derivatives, and 4,4'-diphenylmethane diisocyanate (MDI), 4,4'-methylenebis (2,6-dimethylphenyl isocyanate), 4,4'-me Renbis (2,6-diethylphenyl isocyanate), 4,4'-methylenebis (2,6-di-t-butylphenyl isocyanate), 4,4'-methylenebis (2,6-dicyclohexylphenyl isocyanate), 4,4'-methylenebis (2-methylphenylisocyanate), 4,4'-methylenebis (2-ethylphenylisocyanate), 4,4'-methylenebis (2-t-butylphenylisocyanate), 4,4 '-Methylenebis (2-cyclohexylphenyl isocyanate), 4,4'-methylenebis (3,5-dimethylphenylisocyanate), 4,4'-methylenebis (2,3-dimethylphenylisocyanate), 4,4' -Methylenebis (2,5-dimethylphenyl isocyanate), 2,2-bis (4- Isocyanatophenyl) hexafluoropropane, 2,2-bis (4-isocyanatophenyl) propane, 1,1-bis (4-isocyanatophenyl) cyclohexane, α, α-bis (4-isocyanatophenyl) toluene, 4,4'-methylenebis (2,6-dichlorophenylisocyanate), 4,4'-methylenebis (2-chlorophenylisocyanate), 4,4'-methylenebis (2,3-dibromophenylisocyanate), m-xyl Range isocyanate, 4,4'-diisocyanate-3,3'-dimethylbiphenyl, 1,5-diisocyanatonaphthalene, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 2, 4-toluene diisocyanate (2,4-TDI), 2,6-toluene di Isocyanate (2,6-TDI), 1,3-bis (2-isocyanato-2-propyl) benzene, 1,3-bis (isocyanatomethyl) cyclohexane, dicyclohexylmethane-4,4'-diisocyanate , Isophorone diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, 2,7-full orange isocyanate, benzophenone-4,4'-diisocyanic acid, 3,3'-dichlorobenzophenone-4,4'-diisocyanate Acid, 5,5'-diethyl-3,3'-difluorobenzophenone-4,4'-diisocyanic acid, 2,2-bis (4-isocyanatophenyl) propane, 2,2-bis (3,5-dichloro- 4-isocyanatophenyl) propane, 2,2-bis (4-isocyanate) Phenphenyl) hexafluoropropane, 2,2-bis (3-fluoro-4-isocyanatophenyl) hexafluoropropane, bis (4-isocyanatephenyl) ether, bis (3,5-difluoro-4-isocyanatophenyl) ether, bis (4-isocyanate phenyl) sulfide, bis (3,5-dibromo-4-isocyanate phenyl) sulfide, bis (4-isocyanate phenyl) disulfide, bis (4-isocyanate phenyl) sulfone, bis (4-isocyanate phenyl) sulfoxide, Bis (3,5-difluoro-4-isocyanatophenyl) sulfoxide, 1,1-bis (4-isocyanatophenyl) cyclopropane, 1,1-bis (4-isocyanatophenyl) cyclooctane, 1, -Bis (4-isocyanatophenyl) cyclohexane, 1,1-bis (3,5-dichloro-4-isocyanatophenyl) cyclohexane, 4,4 '-(cyclohexylmethylene) bis (isocyanatebenzene), 4,4'-( Cyclohexylmethylene) bis (1-isocyanate-2-chlorobenzene), diethyl 2,2-bis (4-isocyanatephenyl) malonate, diethyl 2,2-bis (3-chloro-4-isocyanatophenyl) malonate, 4- (Di-p-isocyanatophenylmethyl) pyridine, 1- (di-p-isocyanatophenylmethyl) -1H-pyrrole, 1- (di-p-isocyanatophenylmethyl) -1H-imidazole, 2- (di-p-isocyanatephenylmethyl) Diisocyanate compounds such as oxazole And derivatives thereof, 4,4'-diphenylmethane diisothiocyanate, 4,4'-methylenebis (2,6-diethylphenylisothiocyanate), 4,4'-methylenebis (2,6-di-t- Butylphenyl isothiocyanate), 1,3-bis (isothiocyanatomethyl) cyclohexane, benzophenone-4,4'-diisothiocyanic acid, 3,3'-difluorobenzophenone-4,4'-diisothiocyanic acid, 2, 2-bis (3,5-dichloro-4-isothiocyanatephenyl) propane, bis (4-isothiocyanatephenyl) ether, bis (4-isothiocyanatephenyl) sulfone, bis (4-isothiocyanatephenyl) sulfoxide, bis ( 3,5-difluoro-4-isothiocyanatophenyl) sulfur Xoxide, 1,1-bis (4-isothiocyanatophenyl) cyclopropane, 1,1-bis (4-isothiocyanatophenyl) cyclooctane, 4,4 '-(cyclohexylmethylene) bis (isothiocyanate benzene), 2, Diisothiocyanate compounds such as diethyl 2-bis (4-isothiocyanatephenyl) malonate, 1- (di-p-isothiocyanatophenylmethyl) -1H-pyrrole, 2- (di-p-isothiocyanatephenylmethyl) oxazole and the like Is a derivative.

  Hereinafter, the organic polymer material that can be used in the present invention will be described in more detail.

  In the present invention, the organic polymer material constituting the organic piezoelectric material preferably contains a compound having a urea bond or a thiourea bond as a constituent component, and the compound is represented by the following general formulas (1) to (3). It is also preferable that the compound represented by the formula or derivatives of these compounds be used as a raw material.

(Wherein R ₁₁ and R ₁₂ each independently represent a hydrogen atom, an alkyl group, a 3- to 10-membered non-aromatic cyclic group, an aryl group, or a heteroaryl group, and these groups further have a substituent. R _{21 to} R ₂₆ each independently represents a hydrogen atom, an alkyl group, or an electron-withdrawing group.)

(In the formula, each R ₁₃ independently represents a carboxyl group, a hydroxy group, a mercapto group, or an amino group, and these active hydrogens are further an alkyl group, a 3- to 10-membered non-aromatic ring group, an aryl group, or may be substituted with a heteroaryl group, etc., and, R ₁₃ represents a carbonyl group, a sulfonyl group, a thiocarbonyl group, a sulfone group, these substituents bonded hydrogen atom, an aryl group or a heteroaryl group, R _{21 to} R ₂₆ represent a group having the same meaning as R _{21 to} R _{26 in} the general formula (5).

(Wherein, Y each independently represents a keto group, an oxime group, a substituted vinylidene _group, R 21 _{to R 26} represents _R 21 _{to R 26} as defined substituents in formula (1).)
Preferable examples include compounds represented by the general formulas (1) to (3) or derivatives of these compounds.

<< Compound Represented by Formula (1) >>
Examples of the compound represented by the general formula (1) include 2,7-diaminofluorene, 2,7-diamino-4,5-dinitrofluorene, 2,7-diamino-3,4,5, 6-tetrachlorofluorene. 2,7-diamino-3,6-difluorofluorene, 2,7-diamino-9- (n-hexyl) fluorene, 9,9-dimethyl-2,7-diaminofluorene, 2,7-diamino-9- Benzylfluorene, 9,9-bisphenyl-2,7-diaminofluorene, 2,7-diamino-9-methylfluorene, 9,9-bis (3,4-dichlorophenyl) -2,7-diaminofluorene, 9, 9-bis (3-methyl-4-chlorophenyl) -2,7-diaminofluorene, 9,9-bis (methyloxyethyl) -2,7-diaminofluorene, 2,7-di Mino-3,6-dimethyl-9-aminomethyl fluorene, and the like although not limited thereto.

<< Compound Represented by Formula (2) >>
Examples of the compound represented by the general formula (2) include 2,7-diamino-9-fluorenecarboxylic acid, 2,7-diamino-9-fluorenecarboxaldehyde, 2,7-diamino-9-hydroxyfluorene, 2, 7-diamino-3,6-difluoro-9-hydroxyfluorene, 2,7-diamino-4,5-dibromo-9-mercaptofluorene, 2,7,9-triaminofluorene, 2,7-diamino-9- Hydroxymethylfluorene, 2,7-diamino-9- (methyloxy) fluorene, 2,7-diamino-9-acetoxyfluorene, 2,7-diamino-3,6-diethyl-9- (perfluorophenyloxy) fluorene 2,7-diamino-4,5-difluoro-9- (acetamido) fluorene, 2,7-diamino-N-isopropyl Rufuruoren 9-carboxamide, 2,7-diamino-4,5-dibromo-9-methylsulfinyl fluorene, but like not limited.

<< Compound Represented by Formula (3) >>
As the compound represented by the general formula (3), 9,9-dimethyl-2,7-diaminofluorenone, 2,7-diamino-9-benzylfluorenone, 9,9-bisphenyl-2,7-diaminofluorenone 2,7-diamino-9-methylfluorenone, 9,9-bis (3,4-dichlorophenyl) -2,7-diaminofluorenone, 9,9-bis (3-methyl-4-chlorophenyl) -2,7 -Diaminofluorenone, 9-hexylidene-2,7-diamino-4,5-dichlorofluorene, 1- (2,7-diamino-9-fluorenylidene) -2-phenylhydrazine, 2-((2,7-diamino- 1,8-dimethyl-9-fluorenylidene) methyl) pyridine, and the like.

  In the present invention, for example, the above fluorene exemplified compound is reacted with an aliphatic or aromatic diol, diamine, diisocyanate, diisothiocyanate or the like to form a polyurea or polyurethane structure, and then the following general formulas (4) to ( It can also be mixed with the compound represented by 6) or a high molecular weight product formed from them to form a composite material.

(In the formula, each Ra independently represents a hydrogen atom, an alkyl group, an aryl group, an alkyl group containing an electron-withdrawing group, an aryl group or a heteroaryl group containing an electron-withdrawing group. X is a carbon that can be bonded. Or n may be absent, and n represents an integer of X valence of −1 or less.)
Examples of the compound represented by the compound represented by the general formula (4) include p-acetoxystyrene, p-acetylstyrene, p-benzoylstyrene, p-trifluoroacetylstyrene, p-monochloroacetylstyrene, p- (par Fluorobutyryloxy) styrene, p- (perfluorobenzoyloxy) styrene, S-4-vinylphenylpyridine-2-carbothioate, and N- (4-vinylphenyl) picolinamide, etc. Absent.

(In the formula, each Rb independently represents an alkyl group containing an electron-withdrawing group, an aryl group or a heteroaryl group containing an electron-withdrawing group. X may or may not be an atom other than carbon that can be bonded. n is the valence of X-1 or less.)
Examples of the compound represented by the general formula (5) include p-trifluoromethylstyrene, p-dibromomethylstyrene, p-trifluoromethoxystyrene, p-perfluorophenoxystyrene, and p-bis (trifluoromethyl) aminostyrene. , And p- (1H-imidazolyloxy) styrene, but are not limited thereto.

(In the formula, each Rc independently represents an alkyl group containing an electron-withdrawing group, an aryl group or a heteroaryl group containing an electron-withdrawing group. X may or may not be an atom other than carbon that can be bonded. n represents an integer of X valence of −1 or less.)
Examples of the compound represented by the general formula (6) include p- (methanesulfonyloxy) styrene, p- (trifluoromethanesulfonyloxy) styrene, p-toluenesulfonylstyrene, p- (perfluoropropylsulfonyloxy) styrene, p. Examples include-(perfluorobenzenesulfonyloxy) styrene, (4-vinylphenyl) bis (trifluoromethanesulfonyl) amide, and the like.

  In the present invention, alcohol compounds such as ethylene glycol, glycerin, triethylene glycol, polyethylene glycol, polyvinyl alcohol, and 4,4-methylenebisphenol, ethanolamine having both an amino group and a hydroxyl group, aminobutylphenol, 4- Amino alcohols such as (4-aminobenzyl) phenol (ABP), aminophenols, and the like can also be used.

《Macromonomer》
In the present invention, it is also a preferred embodiment that the compound having a urea bond or thiourea bond is formed using a macromonomer having a molecular weight of 400 to 10,000 as a raw material.

In the present application, the “macromonomer” has a polymerizable functional group such as an isocyanate group, a group having active hydrogen, or a vinyl group at least at one end of the molecular chain, and a urea bond (—NR ₁ CONR ₂ -), thiourea bond _(-NR 3 CSNR ₄ -), urethane bond (-OCONR ₁ -), an amide bond (-CONR ₁ -), ether bond (-O-), an ester bond (-CO ₂ -) and carbonate A compound having two or more bonds selected from a bond (—CO ₂ —).

In the present application, R ₁ in the “urethane bond” is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms (methyl group, ethyl group, propyl group, isopropyl group, tert-butyl group, pentyl group, hexyl group, A cyclohexyl group or the like, preferably a hydrogen atom or an alkyl group having 5 or less carbon atoms, more preferably a hydrogen atom or a methyl group. Further, "amide bond" _{R 1} in the hydrogen atom or an alkyl group having 1 to 10 carbon atoms (a methyl group, an ethyl group, a propyl group, an isopropyl group, tert- butyl group, a pentyl group, a hexyl group, a cyclohexyl group) And preferably a hydrogen atom or an alkyl group having 5 or less carbon atoms, more preferably a hydrogen atom or a methyl group.

  The macromonomer according to the present invention preferably has a urea bond or thiourea bond having a dipole moment. That is, since the macromonomer according to the present invention can introduce a plurality of bonds and linking groups having a dipole moment by sequentially condensing a monomer having a reactive group, a resin composition that has been difficult in the past. It is possible to adjust the solubility and rigidity of the material by selecting the raw material. Moreover, since the influence of the residual monomer can be eliminated by using the macromonomer as a raw material, the heat resistance and piezoelectric characteristics as the piezoelectric material can be remarkably improved.

The “urea bond” is represented by the general formula: —NR ₁ CONR ₂ —. The “thiourea bond” is represented by the general formula: —NR ₃ CSNR ₄ —.

Here, R ₁ and R ₂ are each independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms (methyl group, ethyl group, propyl group, isopropyl group, tert-butyl group, pentyl group, hexyl group, cyclohexyl group). Etc., preferably a hydrogen atom or an alkyl group having 5 or less carbon atoms, more preferably a hydrogen atom or a methyl group.

  The urea bond or thiourea bond may be formed by any means, but can be obtained by a reaction of an isocyanate and an amine or an isothiocyanate and an amine. Also, 1,3-bis (2-aminoethyl) urea, 1,3-bis (2-hydroxyethyl) urea, 1,3-bis (2-hydroxypropyl) urea, 1,3-bis (2-hydroxy) Methyl) thiourea, 1,3-bis (2-hydroxyethyl) thiourea, 1,3-bis (2-hydroxypropyl) thiourea, and the like substituted with an alkyl group having a hydroxyl group or an amino group at the terminal A macromonomer may be synthesized using a compound as a raw material.

  The isocyanate used as a raw material is not particularly limited as long as it is a polyisocyanate having two or more isocyanate groups in the molecule, but is preferably an alkyl polyisocyanate or an aromatic polyisocyanate, and more preferably an alkyl diisocyanate or an aromatic diisocyanate. Moreover, you may use asymmetrical diisocyanate (for example, p-isocyanate benzyl isocyanate etc.) together as a raw material.

  Alkyl polyisocyanate is a compound in which a plurality of isocyanate groups are all present via an alkyl chain. For example, 1,3-bis (isocyanatomethyl) cyclohexane, isophorone diisocyanate, trimethylene diisocyanate, tetramethylene diisocyanate , Pentamethylene diisocyanate, hexamethylene diisocyanate, 1,3-cyclopentane diisocyanate and the like.

  An aromatic polyisocyanate is a compound in which a plurality of isocyanate groups are all directly bonded to an aromatic ring. For example, 9H-fluorene-2,7-diisocyanate, 9H-fluoren-9-one-2,7- Diisocyanate, 4,4'-diphenylmethane diisocyanate, 1,3-phenylene diisocyanate, tolylene-2,4-diisocyanate, tolylene-2,6-diisocyanate, 1,3-bis (isocyanatomethyl) ) Cyclohexane, 2,2-bis (4-isocyanatophenyl) hexafluoropropane, 1,5-diisocyanatonaphthalene and the like.

  The amine used as a raw material is preferably a polyamine having two or more amino groups in the molecule, and most preferably a diamine. Examples of polyamines include 2,7-diamino-9H-fluorene, 3,6-diaminoacridine, acriflavine, acridine yellow, 2,2-bis (4-aminophenyl) hexafluoropropane, and 4,4'-diaminobenzophenone. Bis (4-aminophenyl) sulfone, 4,4′-diaminodiphenyl ether, bis (4-aminophenyl) sulfide, 1,1-bis (4-aminophenyl) cyclohexane, 4,4′-diaminodiphenylmethane, 3, 3'-diaminodiphenylmethane, 3,3'-diaminobenzophenone, 4,4'-diamino-3,3'-dimethyldiphenylmethane, 4- (phenyldiazenyl) benzene-1,3-diamine, 1,5-diaminonaphthalene, 1,3-phenylenediamine, 2,4-diamy Toluene, 2,6-diaminotoluene, 1,8-diaminonaphthalene, 1,3-diaminopropane, 1,3-diaminopentane, 2,2-dimethyl-1,3-propanediamine, 1,5-diaminopentane, 2-methyl-1,5-diaminopentane, 1,7-diaminoheptane, N, N-bis (3-aminopropyl) methylamine, 1,3-diamino-2-propanol, diethylene glycol bis (3-aminopropyl) Ether, m-xylylenediamine, tetraethylenepentamine, 1,3-bis (aminomethyl) cyclohexane, benzoguanamine, 2,4-diamino-1,3,5-triazine, 2,4-diamino-6-methyl- 1,3,5-triazine, 6-chloro-2,4-diaminopyrimidine, 2-chloro-4,6-diamidine 1,3,5-triazine. These polyamines may be reacted with phosgene, triphosgene or thiophosgene to synthesize polyisocyanates or polyisothiocyanates (hereinafter referred to as polyiso (thio) cyanates) and used as macromonomer raw materials. It may be used as an extender.

  When synthesizing a macromonomer, it is possible to synthesize a macromonomer having a high degree of order by utilizing the difference in reactivity between an amino group and a hydroxyl group. For this reason, the macromonomer preferably has at least one urethane bond. The urethane bond can be obtained by a reaction between a hydroxyl group and an isocyanate group, and examples of the compound having a hydroxyl group include polyols, amino alcohols, aminophenols, and alkylaminophenols. A polyol or an amino alcohol is preferable, and an amino alcohol is more preferable.

  The polyol is a compound having at least two hydroxyl groups in the molecule, and preferably a diol. Examples of the polyol include ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, polyethylene glycol, polytetramethylene glycol, 1,4-cyclohexanedi Methanol, pentaerythritol, 3-methyl-1,5-pentanediol, poly (ethylene adipate), poly (diethylene adipate), poly (propylene adipate), poly (tetramethylene adipate), poly (hexamethylene adipate), poly ( Neopentylene adipate) and the like.

  Aminoalcohol is a compound having an amino group and a hydroxyl group in the molecule, such as aminoethanol, 3-amino-1-propanol, 2- (2-aminoethoxy) ethanol, 2-amino-1,3-propane. Examples include diol, 2-amino-2-methyl-1,3-propanediol, and 1,3-diamino-2-propanol. These compounds having a hydroxyl group may be used as a chain extender.

  The macromonomer may have an amide bond, a carbonate bond, etc. in addition to a urea bond, a thiourea bond, a urethane bond, an ester bond, and an ether bond.

  The macromonomer has a molecular weight of 400 to 10,000, but may have a molecular weight distribution because a dimer or a trimer is generated at the stage of sequential synthesis. The molecular weight is a weight average molecular weight obtained by measurement of gel permeation chromatography (hereinafter referred to as “GPC”), preferably 400 to 5000, and more preferably 400 to 3000. The molecular weight distribution is preferably 1.0 to 6.0, more preferably 1.0 to 4.0, and particularly preferably 1.0 to 3.0.

  In addition, the measurement of molecular weight and molecular weight distribution can be performed based on the following method and conditions.

Solvent: 30 mM LiBr in N-methylpyrrolidone Device: HLC-8220GPC (manufactured by Tosoh Corporation)
Column: TSKgel SuperAWM-H x 2 (manufactured by Tosoh Corporation)
Column temperature: 40 ° C
Sample concentration: 1.0 g / L
Injection volume: 40 μl
Flow rate: 0.5 ml / min
Calibration curve: Standard polystyrene: PS-1 (manufactured by Polymer Laboratories) Mw = 580 to 2,560,000 calibration curves with 9 samples were used.

  In the present invention, since a resin composition having piezoelectric characteristics is obtained by polymerizing the macromonomer, at least one of the macromonomer terminals is an isocyanate group, a group having active hydrogen, a vinyl group, an acryloyl group, or a meta group. An acryloyl group is preferred. Examples of the group having active hydrogen include an amino group, a hydroxyl group, a carboxyl group, an imino group, and a thiol group, preferably an amino group, a hydroxyl group, or a carboxyl group, and more preferably an amino group or a hydroxyl group. It is.

  In order to improve the orientation of the macromonomer or polymerized resin composition, it is preferable to polymerize with a compound having a large dipole moment in the molecule as in the general formulas 4-6.

  In order to improve the orientation of the macromonomer or polymerized resin composition, it is preferable to have at least one aromatic condensed ring structure as a partial structure of the macromonomer. Examples of the aromatic condensed ring structure include naphthalene structure, quinoline structure, anthracene structure, phenanthrene structure, pyrene structure, triphenylene structure, perylene structure, fluoranthene structure, indacene structure, acenaphthylene structure, fluorene structure, fluoren-9-one structure, Examples thereof include a carbazole structure, a tetraphenylene structure, and a structure further condensed with these structures (for example, an acridine structure, a benzoanthracene structure, a benzopyrene structure, a pentacene structure, a coronene structure, a chrysene structure, etc.).

  Preferable aromatic condensed ring structures include structures of the following general formulas (ACR1) to (ASR4).

In the general formula (ACR1), R ₁₁ and R ₁₂ each independently represent a hydrogen atom or a substituent. Examples of the substituent include an alkyl group having 1 to 25 carbon atoms (methyl group, ethyl group, propyl group, Isopropyl group, tert-butyl group, pentyl group, hexyl group, cyclohexyl group etc., cycloalkyl group (cyclohexyl group, cyclopentyl group etc.), aryl group (phenyl group etc.), heterocyclic group (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, tetrazolyl group, etc.), alkoxy group (methoxy group, ethoxy group, propyloxy group, Pentyloxy group, cyclopentyloxy group, hexyloxy Group, cyclohexyloxy group, etc.), aryloxy group (phenoxy group, etc.), acyloxy group (acetyloxy group, propionyloxy group, etc.), alkoxycarbonyl group (methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, etc.) , Aryloxycarbonyl group (phenyloxycarbonyl group, etc.), sulfonamide group (methanesulfonamide group, ethanesulfonamide group, butanesulfonamide group, hexanesulfonamide group, cyclohexanesulfonamide group, benzenesulfonamide group, etc.), carbamoyl Groups (aminocarbonyl group, methylaminocarbonyl group, dimethylaminocarbonyl group, propylaminocarbonyl group, pentylaminocarbonyl group, cyclohexylaminocarbonyl group, phenylamino Carbonyl group, 2-pyridylaminocarbonyl group and the like), carboxyl group, hydroxyl group and the like. A hydrogen atom, a hydroxyl group, a carboxyl group, an alkoxy group, an acyloxy group or an alkyl group is preferred, a hydrogen atom, an alkyl group, a hydroxyl group or an acyloxy group is more preferred, and a hydrogen atom or an alkyl group is particularly preferred. is there.

  An asterisk (*) represents a coupling point.

In the general formula (ACR2), X ₂ represents an oxygen atom, N—R ₂₃ , or C—R ₂₄ , and R ₂₃ represents a hydrogen atom, a hydroxyl group, an alkoxy group, an alkyl group, or an amino group, preferably A hydroxyl group or an alkoxy group; R ₂₄ represents an alkyl group, an aryl group or a heterocyclic group, preferably an alkyl group or an aryl group, and particularly preferably an alkyl group.

  An asterisk (*) represents a coupling point.

In General Formula (ACR3), X ₃ represents a nitrogen atom or N + —R ₃₃ , and R ₃₃ represents an alkyl group or an aryl group. If X ₃ is N +, it may have a counter ion for neutralizing a charge, the counter ion, Cl-, Br-, I-, BF 4 - , and the like.

  An asterisk (*) represents a coupling point.

  In the general formula (ACR4), an asterisk (*) represents a bonding point.

  These aromatic condensed ring structures may have a substituent. Examples of the substituent include a halogen atom, an alkyl group having 1 to 25 carbon atoms (methyl group, ethyl group, propyl group, isopropyl group, tert-butyl group). Group, pentyl group, hexyl group, cyclohexyl group, etc.), 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, aryl group (phenyl group, etc.), heterocyclic group (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, Tetrazo Group), halogen atom (chlorine atom, bromine atom, iodine atom, fluorine atom, etc.), alkoxy group (methoxy group, ethoxy group, propyloxy group, pentyloxy group, cyclopentyloxy group, hexyloxy group, cyclohexyloxy group) ), Aryloxy groups (phenoxy group, etc.), alkoxycarbonyl groups (methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, etc.), aryloxycarbonyl groups (phenyloxycarbonyl group, etc.), sulfonamide groups (methane) Sulfonamide group, ethanesulfonamide group, butanesulfonamide group, hexanesulfonamide group, cyclohexanesulfonamide group, benzenesulfonamide group, etc.), sulfamoyl group (aminosulfonyl group, methylaminosulfonyl group, dimethyl group) Ruaminosulfonyl group, butylaminosulfonyl 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, methyl group) Aminocarbonyl group, dimethylaminocarbonyl group, propylaminocarbonyl group, pentylaminocarbonyl group, cyclohexylaminocarbonyl group, phenylaminocarbonyl group, 2-pyridylamino Carbonyl group etc.), amide group (acetamide 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, carboxyl group, hydroxyl group, etc. Can be mentioned. These groups may be further substituted with these groups. When there are a plurality of substituents, they may be the same or different, and may be bonded to each other to form a condensed ring structure. Preferred is a hydrogen atom, halogen atom, amide group, alkyl group or aryl group, more preferred is a hydrogen atom, halogen atom, amide group or alkyl group, and particularly preferred is a hydrogen atom, halogen atom or alkyl group. is there.

  Specific examples of preferred aromatic condensed ring structures are listed below, but the present invention is not limited thereto.

《Synthesis of macromonomer》
The macromonomer is a method in which a compound having active hydrogen is used as a starting material, and a polyiso (thio) cyanate and a compound having active hydrogen are alternately condensed, and a compound having active hydrogen having a polyiso (thio) cyanate as a starting material Polyiso (thio) cyanate can be synthesized by a method of alternately condensing.

  Examples of the compound having active hydrogen include the urea compounds substituted with an alkyl group having a hydroxyl group or an amino group at the terminal, polyamine, polyol, aminoalcohol, aminophenol, alkylaminophenol, and the like. As a starting material, a urea compound or polyamine substituted with an alkyl group having a hydroxyl group or an amino group at a terminal is preferable, and a polyamine having an aromatic condensed ring structure is more preferable. When used in the step of alternately condensing, amino alcohol or polyol is preferable.

  When polyiso (thio) cyanate is used as a starting material, the starting material is preferably a polyiso (thio) cyanate having an aromatic condensed ring structure. A compound having active hydrogen at the terminal may be synthesized by condensing with a compound having active hydrogen, or a diamine may be formed by the method described in JP-A No. 5-115842.

  In addition, by reacting 3-chloro-1-butene, allyl chloride, acryloyl chloride or methacryloyl chloride with a macromonomer having active hydrogen at the terminal, a macro having a vinyl group, acryloyl group or methacryloyl group at the terminal Monomers can be synthesized.

  In the reaction of a compound having active hydrogen with polyiso (thio) cyanate, when at least one terminal is an isocyanate group, the amount of polyiso (thio) cyanate used for the compound having active hydrogen is 1 to 10 moles. Preferably, it is 1 to 5 times mole, more preferably 1 to 3 times mole.

  In the reaction of the compound having active hydrogen with polyiso (thio) cyanate, when at least one of the terminals is active hydrogen, the compound having active hydrogen is used in an amount of 1 to 10 moles relative to polyiso (thio) cyanate. Preferably, it is 1 to 5 times mole, more preferably 1 to 3 times mole.

  The reaction temperature to be condensed is preferably as low as possible, and is −40 to 60 ° C., preferably −20 to 30 ° C., and more preferably −10 to 10 ° C. The reaction temperature may be a constant temperature from the start to the end of the reaction, or may be initially low and then increased.

  As the solvent used for the reaction, it is necessary to use a highly polar solvent in order that the target resin composition is highly polar and the polymerization proceeds efficiently. For example, it is preferable to select a highly polar aprotic solvent such as DMF (N, N-dimethylformamide), DMAc (N, N-dimethylacetamide), DMSO (dimethylsulfoxide), NMP (N-methylpyrrolidone), As long as the reaction substrate and target compound dissolve well, aliphatic hydrocarbons such as cyclohexane, pentane and hexane, aromatic hydrocarbons such as benzene, toluene and chlorobenzene, THF (tetrahydrofuran), diethyl ether, ethylene glycol diethyl It may be a solvent such as ethers such as ether, ketones such as acetone, methyl ethyl ketone, 4-methyl-2-pentanone, esters such as methyl propionate, ethyl acetate, butyl acetate, etc. May be.

  In order to efficiently promote urethane bond formation, tertiary alkylamines such as N, N, N ′, N′-tetramethyl-1,3-butanediamine, triethylamine, tributylamine, 1,4-diazabicyclo [2. 2.2] Known urethane bond formation catalysts such as condensed amines such as octane and 1,8-diazabicyclo [5.4.0] unde-7-ene, and alkyltins such as DBTL, tetrabutyltin and tributyltin acetate Can be used.

  The amount of the catalyst used is preferably 0.1 to 30 mol% based on the monomer substrate in consideration of efficient reaction and reaction operation.

  The macromonomer may be isolated for each condensation step or synthesized in one pot, but it is preferable to perform isolation and purification at the time of forming a compound having a terminal active hydrogen.

  The macromonomer may be purified by any means, but purification by reprecipitation is preferred. The reprecipitation method is not particularly limited, but a method in which the macromonomer is dissolved in a good solvent and then dropped into a poor solvent to cause precipitation is preferable.

  The “good solvent” as used herein may be any solvent as long as it dissolves the macromonomer, but is preferably a polar solvent, specifically, DMF (N, N-dimethylformamide), DMAc. Examples thereof include highly polar aprotic solvents such as (N, N-dimethylacetamide), DMSO (dimethyl sulfoxide), and NMP (N-methylpyrrolidone).

  The “poor solvent” may be any solvent as long as it does not dissolve the macromonomer, but is an aliphatic hydrocarbon such as cyclohexane, pentane or hexane, or an aromatic hydrocarbon such as benzene, toluene or chlorobenzene. And ethers such as diethyl ether and ethylene glycol diethyl ether, esters such as methyl propionate, ethyl acetate and butyl acetate, and alcohols such as methanol, ethanol and propanol.

  Although the specific example of a macromonomer is given to the following, this invention is not limited to this.

<Synthesis example of macromonomer>
[Synthesis Example 1: Synthesis of Macromonomer (M-8)]
Under a nitrogen atmosphere, 85.27 g of 9H-fluorene-2,7-diisocyanate was dissolved in 850 ml of THF, and 5.0 g of 2-chloro-4,6-diamino-1,3,5-triazine was dissolved in 50 ml of THF at 0 ° C. Slowly dropped. After completion of dropping, the mixture was stirred at 0 ° C. for 1 hour, and further stirred at room temperature for 2 hours. After the solvent in the reaction solution was distilled off by 2/3 by vacuum concentration, reprecipitation was performed using a mixed solvent of ethyl acetate-heptane, and the supernatant was removed by decantation, followed by drying under reduced pressure to obtain a macromonomer (M 20.0 g of -8) was obtained. 1H-NMR confirmed the target product.

[Synthesis Example 2: Synthesis of Macromonomer (M-15)]
40 g of diethylamine and 50 ml of THF were mixed, and 20 g of 9H-fluorene-2,7-diisocyanate dissolved in 50 ml of THF was added dropwise at room temperature. After completion of the dropwise addition, the mixture was stirred at room temperature for 1 hour, and then the precipitate was collected by filtration and washed with THF.

  Subsequently, 30 g of the obtained compound and 180 g of 2,2-dimethyl-1,3-propanediamine were mixed and heated at 120 ° C. The distillate was removed, and when the distillate disappeared, distillation under reduced pressure was performed under reduced pressure until the distillate disappeared. The obtained residue was washed with THF and sufficiently dried to obtain 1,1 ′-(9H-fluorene-2,7-diyl) bis (3- (3-amino-2,2-dimethylpropyl) urea. )

  Under a nitrogen atmosphere, 7 g of p-isocyanate benzyl isocyanate was dissolved in 70 ml of dimethyl sulfoxide, and the reaction solution was cooled to 0 ° C. After slowly dropping 3 g of 1,1 ′-(9H-fluorene-2,7-diyl) bis (3- (3-amino-2,2-dimethylpropyl) urea) dissolved in 30 ml of dimethyl sulfoxide The mixture was stirred at 0 ° C. for 1 hour. After gradually raising the temperature and reacting at room temperature for 1 hour, reprecipitation was performed using ethyl acetate. After removing the supernatant with decant, 6.5 g of macromonomer (M-15) was obtained by drying under reduced pressure. The weight average molecular weight by GPC measurement was 810, and molecular weight distribution was 1.6.

[Synthesis Example 3: Synthesis of Macromonomer (M-31)]
Under nitrogen atmosphere, 5.0 g of 9H-fluorene-2,7-diisocyanate was dissolved in 50 ml of THF, and 3.2 g of 3-aminopropanol dissolved in 30 ml of THF was slowly added dropwise at 0 ° C. After completion of dropping, the mixture was stirred at 0 ° C. for 1 hour to obtain a solution (A).

  13.0 g of 1,3-phenylene diisocyanate was dissolved in 65 ml of THF, and the solution (A) was added dropwise while heating the reaction solution to 70 ° C. After completion of the dropwise addition, the mixture was stirred at 70 ° C. for 5 hours, and then the solvent amount of the reaction solution was concentrated to 3/2 under reduced pressure. A mixed solution of ethyl acetate-heptane was added to the residue and stirred, and the supernatant was removed by decantation and dried under reduced pressure to obtain 12.5 g of a macromonomer (M-31). The weight average molecular weight by GPC measurement was 750, and molecular weight distribution was 2.0.

[Synthesis Example 4: Synthesis of Macromonomer (M-35)]
Under nitrogen atmosphere, 5.0 g of 9H-fluorene-2,7-diisocyanate was dissolved in 50 ml of THF, and 10.0 g of 2- (2-aminoethoxy) ethanol dissolved in 30 ml of THF at room temperature was slowly added dropwise. After completion of dropping, the mixture was stirred at room temperature for 3 hours. The residue was concentrated and then recrystallized to obtain 9.2 g of a macromonomer (M-35). 1H-NMR confirmed the target product.

  As the organic polymer material (hereinafter also referred to as “polymer material”) as a constituent material of the organic piezoelectric material of the present invention, various organic polymer materials that have been conventionally used as piezoelectric materials can also be used. . That is, an embodiment in which the organic piezoelectric material of the present invention is formed of a polymer material containing polyvinylidene fluoride as a main component or a composite material containing a polymer material containing polyvinylidene fluoride as a main component is also preferable.

  For example, as a typical material, an organic polymer material containing vinylidene fluoride as a main component can be used from the viewpoints of good piezoelectric characteristics, availability, and the like.

Specifically, it is preferably a homopolymer of polyvinylidene fluoride having a CF ₂ group having a large dipole moment or a copolymer having vinylidene fluoride as a main component.

  In addition, tetrafluoroethylene, trifluoroethylene, hexafluoropropane, chlorofluoroethylene, etc. can be used as the second component in the copolymer.

  For example, in the case of vinylidene fluoride / trifluoride ethylene copolymer, since the electromechanical coupling constant (piezoelectric effect) in the thickness direction varies depending on the copolymerization ratio, the former copolymerization ratio is 60 to 99 mol%. Furthermore, it is preferable that it is 70-95 mol%.

  A polymer containing 70 to 95 mol% of vinylidene fluoride and 5 to 30 mol% of perfluoroalkyl vinyl ether, perfluoroalkoxyethylene, perfluorohexaethylene, etc. is composed of an inorganic piezoelectric element for transmission and an organic piezoelectric element for reception. In combination with the element, it is possible to suppress the transmission fundamental wave and increase the sensitivity of harmonic reception.

  The polymer piezoelectric material is characterized in that it can be formed into a thin film as compared with an inorganic piezoelectric material made of ceramics, so that it can be used as a vibrator corresponding to transmission and reception of higher frequencies.

"solvent"
As the solvent that can be used in the polymerization in the present invention, solvents generally used for polymer material synthesis can be used, and examples include tetrahydrofuran, acetone, methyl ethyl ketone, ethyl acetate, methylene chloride, chloroform, toluene, hexane, and the like. However, this is not the case.

(Method for producing organic piezoelectric material)
The organic piezoelectric material of the present invention can be produced by using various methods known in the art, but it is possible to cast the layer containing fine particles according to the present invention so as to be in direct contact with the casting support. Our study revealed that this is preferable. Hereafter, the method by this casting is demonstrated.

(Manufacturing process)
The manufacturing method of the organic piezoelectric material of the present invention will be described with reference to the process diagram shown in FIG.

  FIG. 1 is a process diagram showing an example of an organic piezoelectric material manufacturing apparatus of the present invention. Organic Piezoelectric Material An organic piezoelectric material liquid tank 1 for preparing an organic piezoelectric material liquid is charged with an organic piezoelectric material liquid 1a, and a fine particle additive liquid tank 2 is charged with a fine particle additive liquid 2a. The organic piezoelectric material liquid 1a is sent to the in-line mixers 5a and 5b by the liquid feed pumps 4b and 4c, and the fine particle additive liquid 2a is sent to the in-line mixer 5a by the pump 4a. The organic piezoelectric material liquid 1 a and the fine particle additive liquid 2 a are sufficiently mixed by the in-line mixer 5 a and sent to the slit of the slit die 6.

  Similarly, the organic piezoelectric material liquid 1 a and the additive liquid 3 a are sufficiently mixed by the in-line mixer 5 b and sent to the slit of the slit die 6. The upper and lower surface layers from the slit die 6 are composed of a mixed liquid of the organic piezoelectric material liquid 1a and the fine particle additive liquid 2a, and the middle layer is cast in a mixed liquid state of the organic piezoelectric material liquid 1a and the additive liquid 3a. It is cast on the casting belt 8 which is cast from the mouth and continuously moves from the drum 7. The three layers of the organic piezoelectric material liquid layer thus cast are dried, and then peeled off from the casting belt by the roller 9 as a laminated film 10 of the organic piezoelectric material.

  Hereinafter, the co-casting method according to the method for producing the organic piezoelectric material of the present invention will be described in more detail.

  “Co-casting” is a sequential multi-layer casting method in which two or three layers are configured through different dies, and simultaneous multi-layer flow in a die having two or three slits to form a two or three layers. Any of a casting method and a multilayer casting method in which sequential multilayer casting and simultaneous multilayer casting are combined may be used.

  In the present invention, the “liquid in which the organic piezoelectric material is dissolved” is a state in which the organic piezoelectric material is dissolved in a solvent (solvent). The organic piezoelectric material liquid includes a hardener, a plasticizer, Additives such as antioxidants may be added and, of course, other additives may be added as necessary. As solid content concentration in an organic piezoelectric material liquid, 5-30 mass% is preferable, More preferably, it is 10-25 mass%.

  The solvent used in the present invention may be used alone or in combination, but it is preferable to use a mixture of a good solvent and a poor solvent from the viewpoint of production efficiency, and more preferably, the mixing ratio of the good solvent and the poor solvent is good. The solvent is 70 to 99% by mass, and the poor solvent is 30 to 1% by mass. The “good solvent” and “poor solvent” used in the present invention are defined as those that dissolve the organic piezoelectric material used alone as good solvents and those that swell or do not dissolve alone as poor solvents.

  Therefore, the good solvent and the poor solvent vary depending on the type and structure of the organic piezoelectric material.

  Examples of the good solvent used in the present invention include a solvent such as methyl ethyl ketone, dimethylformamide, dimethylacetamide, dimethylformamide, N-methylpyrrolidone and the like.

  Moreover, as a poor solvent used for this invention, methanol, ethanol, n-butanol, a cyclohexane, cyclohexanone etc. are used preferably, for example.

  As a method for dissolving the organic piezoelectric material when preparing the organic piezoelectric material liquid, a general method can be used. However, as a preferable method, the organic piezoelectric material is mixed with a poor solvent, wetted or swollen, Further, a method of mixing with a good solvent is preferably used. At this time, in order to prevent the generation of massive undissolved material called gel or mamako, heating and stirring at a temperature above the boiling point of the solvent at room temperature under pressure and dissolving while stirring It may be used. The pressurization may be performed by a method of injecting an inert gas such as nitrogen gas or by increasing the vapor pressure of the solvent by heating. Heating is preferably performed from the outside. For example, a jacket type is preferable because temperature control is easy.

  The heating temperature with the addition of the solvent is preferably a temperature that is not lower than the boiling point of the solvent used and does not boil, and is preferably set in the range of 40 ° C. or higher and 50 to 100 ° C., for example. The pressure is adjusted at a set temperature so that the solvent does not boil.

  After dissolution, it is taken out from the container while cooling, or extracted from the container with a pump or the like and cooled with a heat exchanger or the like, and used for film formation. Although the cooling temperature at this time may be cooled to room temperature, it is more preferable to cool to a temperature 5 to 10 ° C. lower than the boiling point and perform casting at that temperature because the viscosity of the organic piezoelectric material liquid can be reduced.

  For example, in the production of an organic piezoelectric material having two or more layers according to the present invention, an organic piezoelectric material solution in which an organic piezoelectric material is dissolved in a solvent and a solution in which fine particles and a small amount of the organic piezoelectric material are dissolved are mixed with an in-line mixer. Organic piezoelectric material liquid A prepared by mixing and dispersing and organic piezoelectric material liquid B in which the organic piezoelectric material is dissolved (other additives such as a crosslinking agent are added separately in-line as necessary). And using the die slit having a plurality of slits, the organic piezoelectric material liquid A containing fine particles is directly cast on the casting belt so as to be co-cast (casting process), and then , After removing a part of the solvent by heating (drying process on the casting belt), peeling from the casting belt, and drying the peeled film (film drying process), the two or more layers of the present invention Obtained organic piezoelectric material That.

  As the support in the casting step, a support obtained by mirror-finishing belt-shaped or drum-shaped stainless steel is preferably used. The temperature of the support in the casting process can be cast in a general temperature range of 0 ° C. to less than the boiling point of the solvent, but the dope is gelled by casting on a support at 0 to 60 ° C. In order to increase the peeling limit time, it is preferable, and casting on a support at 5 to 40 ° C. is more preferable. The peeling limit time is the time during which the cast organic piezoelectric material liquid is on the support at the limit of the casting speed at which a transparent and flat film can be continuously obtained. A shorter peeling limit time is preferable because of excellent productivity.

  The surface temperature of the support to be cast (cast) is 10 to 80 ° C., the temperature of the solution is 15 to 60 ° C., and the temperature of the solution is preferably higher than the temperature of the support by 0 ° C. or more. More preferably, it is set to 5 ° C. or higher. The higher the solution temperature and the support temperature, the faster the solvent can be dried. However, if the temperature is too high, foaming or flatness may be deteriorated.

  A more preferable range of the temperature of the support is 20 to 40 ° C, and a more preferable range of the solution temperature is 35 to 45 ° C. Moreover, since the adhesive force of an organic piezoelectric material and a support body can be reduced by making the support body temperature at the time of peeling 10-40 degreeC, More preferably, 15-30 degreeC, it is preferable. In order for the organic piezoelectric material at the time of manufacture to exhibit good flatness, the residual solvent amount when peeling from the support is preferably 10 to 80%, more preferably 20 to 40% or 60 to 80%. Yes, and particularly preferably 20 to 30%.

  In the present application, the residual solvent amount is defined by the following formula.

Residual solvent amount = (mass before heat treatment−mass after heat treatment) / (mass after heat treatment) × 100%
The heat treatment when measuring the residual solvent amount represents that the organic piezoelectric material is subjected to heat treatment at a temperature of 100 to 200 ° C. for 1 hour.

  Peeling is usually performed at a peeling tension of 20 to 25 kg / m when peeling the support from the organic piezoelectric material. However, the organic piezoelectric material of the present invention, which is a thin film, is prone to wrinkles during peeling. Peeling is preferably performed at a minimum tension of 17 kg / m, and more preferably, peeling is performed at a minimum tension of 14 kg / m. In the drying process of the organic piezoelectric material, the organic piezoelectric material peeled off from the support is further dried, and the residual solvent amount is preferably 3% by mass or less, more preferably 0.1% by mass or less. .

  In the drying process, generally, a method of drying while conveying the organic piezoelectric material by a roll suspension method or a pin tenter method is adopted. As an organic piezoelectric material, it is preferable to dry while maintaining the width by a pin tenter method in order to improve dimensional stability. In particular, it is particularly preferable to maintain the width in a large amount of residual solvent immediately after peeling from the support because the effect of improving dimensional stability is more exhibited. The means for drying is not particularly limited, and is generally performed with hot air, infrared rays, a heating roll, microwaves, or the like. It is preferable to carry out with hot air in terms of simplicity. The drying temperature is preferably in the range of 30 to 200 ° C. and gradually increased to 3 to 5 stages, and more preferably in the range of 50 to 140 ° C. in order to improve the dimensional stability.

(Organic piezoelectric film)
The organic piezoelectric film according to the present invention can be produced using the above piezoelectric material by various conventionally known methods such as a melting method and a casting method.

  In the present invention, as a method for producing an organic piezoelectric film, basically, a method of applying a solution of the above polymer material or the like on a substrate and drying it, or using a raw material compound of the above polymer material has been conventionally used. A method of forming a polymer film by a known solution polymerization coating method or the like can be employed.

  Specific methods and conditions of the solution polymerization coating method can be carried out according to various conventionally known methods. For example, a method of forming an organic piezoelectric film by applying a mixed solution of raw materials on a substrate, drying to some extent under reduced pressure conditions (after removing the solvent), heating, thermal polymerization, and then or simultaneously performing polarization treatment Is preferred.

  In order to improve the piezoelectric characteristics, it is useful to add a process for aligning the molecular arrangement. Examples of means include stretching film formation and polarization treatment.

  Various known methods can be adopted for the method of stretching film formation. For example, a solution in which the above organic polymer material is dissolved in an organic solvent such as ethyl methyl ketone (MEK) is cast on a substrate such as a glass plate, and the solvent is dried at room temperature to obtain a film having a desired thickness. Then, the film is stretched to a predetermined length at room temperature. The stretching can be performed in a uniaxial / biaxial direction so that the organic piezoelectric film having a predetermined shape is not destroyed. The draw ratio is 2 to 10 times, preferably 2 to 6 times.

(Polarization treatment)
As a polarization treatment method in the polarization treatment according to the present invention, a conventionally known method such as DC voltage application treatment, AC voltage application treatment, or corona discharge treatment 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 the processing environment, it is preferable to select the conditions as appropriate. The voltage of the high voltage power source is preferably -1 to -20 kV, the current is 1 to 80 mA, the distance between the electrodes is preferably 1 to 10 cm, and 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 the case where the organic piezoelectric material of the present invention is subjected to polarization treatment by corona discharge, a planar electrode is disposed so as to be in contact with the first surface of the organic piezoelectric material, and the second electrode is opposed to the first surface. It is preferable that a columnar corona discharge electrode is installed on the surface side of the electrode and the polarization treatment is performed by corona discharge.

  The polarization treatment prevents the oxidation of the surface of the material due to water and oxygen and does not impair the piezoelectricity. For this reason, the absolute mass humidity is 0.004 or less in a nitrogen or rare gas (helium, argon, etc.) stream. The embodiment applied in the environment is preferred. A nitrogen stream is particularly preferable.

  In addition, at least one of an organic piezoelectric material including a planar electrode placed in contact with the first surface or a cylindrical corona discharge electrode provided on the second surface side moves at a constant speed. However, corona discharge is preferably performed.

In the present application, “mass absolute humidity” means that when the mass of water vapor contained in the humid air is m _w [kg] with respect to the mass m _DA [kg] of dry air, The ratio SH (Specific humidity) defined by is expressed in [kg / kg (DA)] (DA is an abbreviation of dry air). However, in the present application, the unit is omitted.

(Formula): SH = m _w / m _DA [kg / kg (DA)]
Here, air containing water vapor is referred to as “wet air”, and air obtained by removing water vapor from the humid air is referred to as “dry air”.

In addition, the definition of mass absolute humidity under nitrogen or rare gas (helium, argon, etc.) airflow is the same as the case of the above-mentioned air, and the moisture vapor contained in the wet gas with respect to the dry gas mass m _DG [kg]. When the mass is m _w [kg], it means the ratio SH defined according to the above formula, and the unit is represented by [kg / kg (DG)] (DG is an abbreviation for dry gas). However, in the present application, the unit is omitted.

  In addition, “installation” means that an existing electrode separately prepared in advance is placed so as to be in contact with the surface of the organic piezoelectric material, or the electrode constituent material is attached to the surface of the organic piezoelectric material by a vapor deposition method or the like. It refers to forming an electrode above.

  In addition, it is preferable that the organic piezoelectric film formed of the organic piezoelectric material of the present invention is formed in an electric field in the formation process, that is, a polarization treatment is performed in the formation process. At this time, a magnetic field may be used in combination.

  In the corona discharge treatment method according to the present invention, the treatment can be performed using a commercially available apparatus 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 supply is 1 to 20 kV for both positive and negative voltages, 1 to 80 mA for the current, and the distance between the electrodes. 0.5-10 cm is preferable, and the applied electric field is preferably 0.5-2.0 MV / m. The organic piezoelectric material or the organic piezoelectric film during the polarization treatment is preferably 50 to 250 ° C, more preferably 70 to 180 ° C.

  As an electrode used for corona discharge, it is necessary to use a columnar electrode as described above in order to perform a polarization treatment uniformly.

  In addition, in this application, it is preferable that the diameter of the circle | round | yen of a cylindrical electrode is 0.1 mm-2 cm. The length of the cylinder is preferably set to an appropriate length according to the size of the organic piezoelectric material to be polarized. For example, in general, the thickness is preferably 5 cm or less from the viewpoint of uniformly performing the polarization treatment.

  These electrodes are preferably stretched at a portion where corona discharge is performed, and can be realized by a method of applying a constant weight to both ends of the electrodes or fixing the electrodes in a state where a constant weight is applied. Moreover, as a constituent material of these electrodes, a general metal material can be used, but gold, silver and copper are particularly preferable.

  In order to perform a uniform polarization process, it is preferable that the planar electrode placed so as to be in contact with the first surface is in close contact with the organic piezoelectric material. That is, it is preferable to perform corona discharge after forming an organic polymer film or an organic piezoelectric film on a substrate provided with a planar electrode.

  In addition, as a manufacturing method of the ultrasonic transducer | vibrator which concerns on this invention, before the formation of the electrode installed in both surfaces of an organic piezoelectric (body) film | membrane, a polarization process is carried out either after an electrode formation on one side or after an electrode formation on both sides It is preferable that it is the manufacturing method of the aspect to do. Moreover, it is preferable that the said polarization process is a voltage application process.

(substrate)
As the substrate, the selection of the substrate varies depending on the use and usage of the organic piezoelectric film according to the present invention. In the present invention, a plastic plate or film such as polyimide, polyamide, polyimide amide, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polymethyl methacrylate (PMMA), polycarbonate resin, or cycloolefin polymer is used. Can do. Further, the surface of these materials may be covered with aluminum, gold, copper, magnesium, silicon or the like. Alternatively, a single crystal plate or film of aluminum, gold, copper, magnesium, silicon alone, or a rare earth halide may be used. The substrate itself may not be used.

(Ultrasonic transducer)
The ultrasonic transducer according to the present invention is characterized by using an organic piezoelectric film formed using the organic piezoelectric material of the present invention. The ultrasonic transducer is preferably an ultrasonic receiving transducer used in an ultrasonic medical diagnostic imaging device probe including an ultrasonic transmitting transducer and an ultrasonic transmitting transducer. .

  In general, an ultrasonic vibrator has a pair of electrodes sandwiched between layers (or films) made of a film-like piezoelectric material (also referred to as “piezoelectric film”, “piezoelectric film”, or “piezoelectric layer”). An ultrasonic probe is configured by arranging a plurality of transducers, for example, one-dimensionally.

  Then, a predetermined number of transducers in the major axis direction in which a plurality of transducers are arranged is set as the aperture, and the plurality of transducers belonging to the aperture are driven to focus the ultrasonic beam on the measurement site in the subject. And has a function of receiving reflected echoes of ultrasonic waves emitted from the subject by a plurality of transducers belonging to the aperture and converting them into electrical signals.

  Hereinafter, each of the ultrasonic wave receiving transducer and the ultrasonic wave transmitting transducer according to the present invention will be described in detail.

<Ultrasound receiving transducer>
An ultrasonic receiving vibrator according to the present invention is a vibrator having an ultrasonic receiving piezoelectric material used for a probe for an ultrasonic medical diagnostic imaging apparatus, and the piezoelectric material constituting the ultrasonic receiving vibrator is an element of the present invention. An embodiment using an organic piezoelectric film formed using an organic piezoelectric material is preferable.

The organic piezoelectric material or the organic piezoelectric film used for the ultrasonic receiving vibrator preferably has a relative dielectric constant of 10 to 50 at the thickness resonance frequency. The relative dielectric constant is adjusted by adjusting the number, composition, degree of polymerization, etc. of the polar functional groups such as the substituent R, CF ₂ group, and CN group of the compound constituting the organic piezoelectric material, and the polarization treatment described above. Can be done by.

  The organic piezoelectric film constituting the receiving vibrator of the present invention can also be configured by laminating a plurality of polymer materials. In this case, as the polymer material to be laminated, the following polymer material having a relatively low relative dielectric constant can be used in addition to the above polymer material.

  In the following examples, the numerical values in parentheses indicate the relative dielectric constant of the polymer material (resin).

  For example, methyl methacrylate resin (3.0), acrylonitrile resin (4.0), acetate resin (3.4), aniline resin (3.5), aniline formaldehyde resin (4.0), aminoalkyl resin ( 4.0), alkyd resin (5.0), nylon-6-6 (3.4), ethylene resin (2.2), epoxy resin (2.5), vinyl chloride resin (3.3), chloride Vinylidene resin (3.0), urea formaldehyde resin (7.0), polyacetal resin (3.6), polyurethane (5.0), polyester resin (2.8), polyethylene (low pressure) (2.3), Polyethylene terephthalate (2.9), polycarbonate resin (2.9), melamine resin (5.1), melamine formaldehyde resin (8.0), cellulose acetate (3.2), acetic acid Sulfonyl resin (2.7), styrene resins (2.3), styrene butadiene rubber (3.0), styrene resin (2.4), it can be used polytetrafluoroethylene (2.0) or the like.

  The polymer material having a low relative dielectric constant is preferably selected in accordance with various purposes such as adjusting the piezoelectric characteristics or imparting the physical strength of the organic piezoelectric film. .

<Transmitter for ultrasonic transmission>
The ultrasonic transmission vibrator according to the present invention is preferably made of a piezoelectric material having an appropriate relative dielectric constant in relation to the vibrator having the receiving piezoelectric material. Moreover, it is preferable to use a piezoelectric material excellent in heat resistance and voltage resistance.

  Various known organic piezoelectric materials and inorganic piezoelectric materials can be used as the ultrasonic transmitting vibrator constituent material.

  As the organic piezoelectric material, a polymer material similar to the above-described organic piezoelectric material for constituting an ultrasonic receiving vibrator can be used.

Inorganic materials include quartz, lithium niobate (LiNbO ₃ ), potassium tantalate niobate [K (Ta, Nb) O ₃ ], barium titanate (BaTiO ₃ ), lithium tantalate (LiTaO ₃ ), or titanate Lead zirconate (PZT), strontium titanate (SrTiO ₃ ), barium strontium titanate (BST), or the like can be used. PZT is preferably Pb (Zr _1-n Ti _n ) O ₃ (0.47 ≦ n ≦ 1).

<electrode>
The piezoelectric (body) vibrator according to the present invention is manufactured by forming electrodes on both surfaces or one surface of a piezoelectric film (layer) and polarizing the piezoelectric film. When producing an ultrasonic wave receiving vibrator using an organic piezoelectric material, the electrode on the first surface used for the polarization treatment may be used as it is. The electrode is formed using an electrode material mainly composed of gold (Au), platinum (Pt), silver (Ag), palladium (Pd), copper (Cu), nickel (Ni), tin (Sn), or the like. .

  In forming the electrodes, first, a base metal such as titanium (Ti) or chromium (Cr) is formed to a thickness of 0.02 to 1.0 μm by sputtering, and then the metal mainly composed of the above metal elements and those A metal material made of the above alloy, and further, if necessary, a part of the insulating material is formed to a thickness of 1 to 10 μm by sputtering, vapor deposition or other suitable methods. In addition to sputtering, these electrodes can be formed by screen printing, dipping, or thermal spraying using a conductive paste in which fine metal powder and low-melting glass are mixed.

  Furthermore, a piezoelectric element is obtained by supplying a predetermined voltage between the electrodes formed on both surfaces of the piezoelectric film to polarize the piezoelectric film.

(Ultrasonic probe)
An ultrasonic probe according to the present invention is a probe for an ultrasonic medical image diagnostic apparatus including an ultrasonic transmission transducer and an ultrasonic reception transducer. The ultrasonic receiving transducer according to the invention is used.

  In the present invention, both transmission and reception of ultrasonic waves may be performed by a single transducer, but more preferably, the transducers are configured separately for transmission and reception in the probe.

  The piezoelectric material constituting the transmitting vibrator may be a conventionally known ceramic inorganic piezoelectric material or an organic piezoelectric material.

  In the ultrasonic probe according to the present invention, the ultrasonic receiving transducer of the present invention can be arranged on or in parallel with the transmitting transducer.

  As a more preferred embodiment, the structure for laminating the ultrasonic receiving transducer of the present invention on the ultrasonic transmitting transducer is good, and in this case, the ultrasonic receiving transducer of the present invention is another high-frequency transducer. You may laminate | stack on the vibrator | oscillator for transmission in the form joined together on the molecular material (The polymer (resin) film, for example, polyester film) whose relative dielectric constant is comparatively low as a support body. In this case, it is preferable that the film thickness of the receiving vibrator and the other polymer material be matched to a preferable receiving frequency band in terms of probe design. Considering a practical ultrasonic medical diagnostic imaging apparatus and biological information collection from a practical frequency band, the film thickness is preferably 40 to 150 μm.

  The probe may be provided with a backing layer, an acoustic matching layer, an acoustic lens, and the like. Also, a probe in which vibrators having a large number of piezoelectric materials are two-dimensionally arranged can be used. A plurality of two-dimensionally arranged probes can be sequentially scanned to form a scanner.

(Ultrasonic medical diagnostic imaging equipment)
The ultrasonic probe according to the present invention can be used for various types of ultrasonic diagnostic apparatuses. For example, it can be suitably used in an ultrasonic medical image diagnostic apparatus as shown in FIGS.

  FIG. 2 is a conceptual diagram showing a configuration of a main part of the ultrasonic medical image diagnostic apparatus according to the embodiment of the present invention. This ultrasonic medical diagnostic imaging apparatus transmits an ultrasonic wave to a subject such as a patient, and an ultrasonic probe in which piezoelectric vibrators that receive ultrasonic waves reflected by the subject as echo signals are arranged. (Probe). In addition, an electric signal is supplied to the ultrasonic probe to generate an ultrasonic wave, and a transmission / reception circuit that receives an echo signal received by each piezoelectric vibrator of the ultrasonic probe, and transmission / reception control of the transmission / reception circuit A transmission / reception control circuit is provided.

  Furthermore, an image data conversion circuit that converts echo signals received by the transmission / reception circuit into ultrasonic image data of the subject is provided. Further, a display control circuit for controlling and displaying the monitor with the ultrasonic image data converted by the image data conversion circuit and a control circuit for controlling the entire ultrasonic medical image diagnostic apparatus are provided.

  A transmission / reception control circuit, an image data conversion circuit, and a display control circuit are connected to the control circuit, and the control circuit controls operations of these units. Then, an electrical signal is applied to each piezoelectric vibrator of the ultrasonic probe to transmit an ultrasonic wave to the subject, and the reflected wave caused by acoustic impedance mismatch inside the subject is detected by the ultrasonic probe. Receive at.

  The transmission / reception circuit corresponds to “means for generating an electrical signal”, and the image data conversion circuit corresponds to “image processing means”.

  According to the ultrasonic diagnostic apparatus as described above, by utilizing the characteristics of the ultrasonic receiving vibrator excellent in piezoelectric characteristics and heat resistance of the present invention and suitable for high frequency and wide band, the image quality and its An ultrasonic image with improved reproduction and stability can be obtained.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated concretely, this invention is not limited to these.

Example 1
(Preparation of organic piezoelectric materials 1-7)
A 0.5 L four-necked separable flask was equipped with a dropping device, a thermometer, a nitrogen gas introduction tube, a stirring device and a reflux condenser, and dehydrated with 25.0 g of 4,4′-diphenylmethane diisocyanate as a monomer at 0 ° C. 100 g of tetrahydrofuran was added and dissolved (ground). Also, 17.2 g of N, N′-dimethylhexamethylenediamine and 100 g of dehydrated tetrahydrofuran at 0 ° C. were mixed and dissolved, dropped into the ground at a rate of 2 g / min in an ice bath, and stirred for 1 hour after the dropping. did. Thereafter, the residue was collected by filtration and washed with acetone adjusted to 0 ° C. The filter cake was dried under reduced pressure to obtain 30.4 g of organic piezoelectric material 1. Other organic piezoelectric materials 2 to 7 were produced in the same manner as the organic piezoelectric material 1 using the materials shown in Table 1.

(Preparation of Comparative Examples 1 to 3)
A 0.5 L four-necked separable flask was equipped with a dropping device, a thermometer, a nitrogen gas introduction tube, a stirring device and a reflux condenser, and dehydrated with 25.0 g of 4,4′-diphenylmethane diisocyanate as a monomer at 0 ° C. 100 g of tetrahydrofuran was added and dissolved (ground). Further, 20.0 g of 4,4′-methylenedianiline and 100 g of dehydrated tetrahydrofuran at 0 ° C. were mixed and dissolved, dropped into the ground at a rate of 2 g / min in an ice bath, and stirred for 1 hour after the dropping. . Thereafter, the residue was collected by filtration and washed with acetone adjusted to 0 ° C. The residue was dried under reduced pressure to obtain 38.7 g of Comparative Example 1. Other Comparative Examples 2 to 3 were produced in the same manner as Comparative Example 1 using the materials shown in Table 1.

(Evaluation of solubility of fabricated organic piezoelectric material)
Using the produced organic piezoelectric materials 1 to 7 and comparative examples 1 to 3, the solubility in 100 g of N-methylpyrrolidone was evaluated. Each organic piezoelectric material 1 to 7 was added by adding 0.5 g of the material to N-methylpyrrolidone that had been temperature-controlled and stirred at 25 ° C., adding 0.5 g if dissolved, and then stopping addition if not dissolved. Each of Comparative Examples 1 to 3 was evaluated.

  The evaluation results are shown in Table 1.

  As is apparent from the results shown in Table 1, in the examples according to the present invention, it can be seen that the solubility is superior to the comparative examples.

Example 2
(Preparation of organic piezoelectric film 1)
A 10% by weight solution of the organic piezoelectric material 1 produced in Example 1 was prepared using NMP as a solvent. After casting, the solution was dried under reduced pressure at 150 ° C. for 2 hours to produce an organic piezoelectric film 1 having a thickness of 40 μm. did. The produced organic piezoelectric film 1 was cut into a length of 50 mm and a width of 5 mm, and measured using a Tensilon RTA-100 type (manufactured by Orientec Co., Ltd.) at a crosshead speed of 50 mm / min at room temperature to obtain an elastic modulus. Other organic piezoelectric materials 2 to 7 and Comparative Examples 1 to 3 were similarly evaluated as organic piezoelectric films.

  The evaluation results are shown in Table 1.

  As is clear from the results shown in Table 1, in the examples according to the present invention, it can be seen that the elastic modulus is smaller than that of the comparative example and the flexibility is excellent.

Example 3
(Preparation of ultrasonic transducer 1)
After the organic piezoelectric film 1 produced in Example 2 was stretched 3 times at room temperature, the temperature was raised to 120 ° C. at a rate of 5 ° C./min while maintaining the stretched length, and after 5 minutes stagnation, It was naturally cooled to 25 ° C. Thereafter, aluminum electrodes are applied to both surfaces of the obtained film by vapor deposition, and corona discharge polarization is performed at an electric field of 2.0 MV / m using a high voltage power supply HARb-20R60 (manufactured by Matsusada Precision Co., Ltd.) and needle electrodes. The ultrasonic transducer using the organic piezoelectric film 1 was manufactured by performing the treatment. Similarly, the ultrasonic vibrators 2 to 7 were produced for the organic piezoelectric films 2 to 7.

(Production of comparative vibrator 1)
The comparative film 1 produced in Example 2 was heated up to 180 ° C. at a rate of 5 ° C./minute, stagnated for 5 minutes, and then naturally cooled to 25 ° C. Thereafter, aluminum electrodes are applied to both surfaces of the obtained film by vapor deposition, and corona discharge polarization is performed at an electric field of 2.0 MV / m using a high voltage power supply HARb-20R60 (manufactured by Matsusada Precision Co., Ltd.) and needle electrodes. Processing was performed to produce a comparative vibrator 1 using the comparative film 1. Similarly, the comparative vibrators 2 and 3 were produced for the comparative films 2 and 3.

(Evaluation of electromechanical coupling constant)
Lead wires made of aluminum foil were bonded to the obtained ultrasonic vibrators 1 to 7 and comparative vibrators 1 to 3, and 4294A PRECISION IMPEDANCE ANALYZER (manufactured by Agilent) was used to obtain electromechanical coupling constants.

  The evaluation results are shown in Table 1.

  As is clear from the results shown in Table 1, it can be seen that in the examples according to the present invention, the electromechanical coupling constant is larger than that of the comparative example, and the electromechanical conversion efficiency is large.

Example 4
<< Evaluation of piezoelectricity of fabricated ultrasonic transducer >>
Evaluation of the obtained ultrasonic transducers 1 to 7 and comparative transducers 1 to 3 is based on a multi-function AFM (manufactured by PACIFIC NANOTECHNOLOGY) equipped with a Nano-R2 / I2 closed-loop linear scanner and FCE-1 type ferroelectric characteristics Piezoelectricity was measured with an evaluation system (manufactured by Toyo Technica).

  The evaluation results are shown in Table 1.

  As is clear from the results shown in Table 1, it can be seen that the piezoelectricity is superior to the comparative example in the examples according to the present invention.

Example 5
(Fabrication and evaluation of the probe)
<Production of piezoelectric material for transmission>
Component raw materials CaCO ₃ , La ₂ O ₃ , Bi ₂ O ₃ and TiO ₂ , and subcomponent raw materials MnO are prepared, and for the component raw materials, the final composition of the components is (Ca _0.97 La _0.03 ) Weighed to be Bi _4.01 Ti ₄ O ₁₅ . Next, pure water was added, mixed in a ball mill containing zirconia media in pure water for 8 hours, and sufficiently dried to obtain a mixed powder. The obtained mixed powder was temporarily molded and calcined in air at 800 ° C. for 2 hours to prepare a calcined product. Next, pure water was added to the obtained calcined material, finely pulverized in a ball mill containing zirconia media in pure water, and dried to prepare a piezoelectric ceramic raw material powder. In pulverization, the piezoelectric ceramic raw material powder having a particle diameter of 100 nm was obtained by changing the pulverization time and pulverization conditions. 6% by mass of pure water as a binder is added to each piezoelectric ceramic raw material powder having a different particle diameter, press-molded to form a plate-shaped temporary molded body having a thickness of 100 μm, and this plate-shaped temporary molded body is vacuum-packed and then 235 MPa. It shape | molded by the press with the pressure of. Next, the molded body was fired. The final sintered body had a thickness of 20 μm. The firing temperature was 1100 ° C. An electric field of 1.5 × Ec (MV / m) or more was applied for 1 minute to perform polarization treatment.

<Production of laminated resonator for reception>
A laminated vibrator was produced in which the organic piezoelectric film 1 produced in Example 1 and a polyester film having a thickness of 50 μm were bonded together with an epoxy adhesive. Thereafter, polarization treatment was performed in the same manner as described above.

  Next, according to a conventional method, an ultrasonic probe was prototyped by laminating a laminated receiver for reception on the above-described piezoelectric material for transmission and installing a backing layer and an acoustic matching layer.

  As a comparative example, in place of the above laminated resonator for reception, a laminated resonator for reception using only a polyvinylidene fluoride copolymer film (organic piezoelectric film) was laminated on the above laminated resonator. A probe similar to the above-described ultrasonic probe was produced.

  Next, the above two types of ultrasonic probes were evaluated by measuring the reception sensitivity and the dielectric breakdown strength.

Incidentally, the reception sensitivity is originating the fundamental frequency _{f 1} of 5 MHz, to determine the received relative sensitivity of 20MHz as 15 MHz, 4 harmonics as received second harmonic wave _{f 2} as 10 MHz, 3 harmonic. For the relative sensitivity of reception, a sound intensity measurement system Model 805 (1 to 50 MHz) manufactured by Sonora Medical System, Inc. (2021 Miller Drive Longmont, Colorado (0501 USA)) was used.

  The dielectric breakdown strength was measured by multiplying the load power P by 5 times, testing for 10 hours, and then returning the load power to the reference to evaluate the relative reception sensitivity. The sensitivity was evaluated as good when the decrease in sensitivity was within 1% before the load test, more than 1% and less than 10%, and 10% or more as bad.

  In the above evaluation, the probe including the receiving piezoelectric (body) laminated vibrator according to the present invention has a relative receiving sensitivity about 1.2 times that of the comparative example, and the dielectric breakdown strength is It was confirmed to be good. That is, it was confirmed that the ultrasonic wave receiving transducer of the present invention can be suitably used for a probe used in an ultrasonic medical image diagnostic apparatus as shown in FIG.

Process drawing which shows an example of the manufacturing apparatus of the organic piezoelectric material of this invention Conceptual diagram showing the configuration of the main part of an ultrasonic medical diagnostic imaging apparatus Appearance block diagram of ultrasonic medical diagnostic imaging equipment

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Organic piezoelectric material liquid tank 1a Organic piezoelectric material liquid 2 Fine particle additive liquid tank 2a Fine particle additive liquid 3 Additive liquid tank 3a Additive liquid 4a, 4b, 4c, 4d Pump 5a, 5b In-line mixer 6 Slit die 7 Drum 8 Casting Belt 9 Roller 10 Organic piezoelectric material P1 Receiving piezoelectric material (film)
P2 Support P3 Transmission piezoelectric material (film)
P4 Backing layer P5 Electrode P6 Acoustic lens S Ultrasound medical image diagnostic device S1 Body of ultrasonic medical image diagnostic device S2 Ultrasonic probe S3 Operation input unit S4 Display unit

Claims (8)

An organic piezoelectric material comprising an organic polymer material having a structure represented by the following general formula (UP1), wherein an electromechanical coupling constant is 0.2 or more.

(In the formula, R ₁ and R ₂ each independently represent an alkylene group, an arylene group or a heteroarylene group. X represents an oxygen atom or a sulfur atom. R ₃ and R ₄ each independently represent hydrogen. Represents an atom, an alkyl group, an aryl group or a heteroaryl group, except when R ₃ and R ₄ are simultaneously hydrogen atoms.) The organic piezoelectric material according to claim 1, wherein the general formula (UP1) is represented by the following general formula (UP2).

(In the formula, R ₁ and R ₂ each independently represent an alkylene group, an arylene group, or a heteroarylene group. R ₇ is a methyl group, an ethyl group, or a propyl group.) 3. The organic piezoelectric material according to claim 1, wherein the organic piezoelectric material contains an organic polymer material formed using a macromonomer having a molecular weight of 400 to 10,000 as a raw material. An organic piezoelectric film formed using the organic piezoelectric material according to claim 1. An ultrasonic transducer comprising an organic piezoelectric film formed using the organic piezoelectric material according to any one of claims 1 to 3, wherein the organic piezoelectric film has electrodes on both sides thereof. And it is an organic piezoelectric film manufactured by polarization treatment either before the formation of the electrodes placed on both sides of the organic piezoelectric film, after the electrode formation on only one side, or after the electrode formation on both sides. Ultrasonic vibrator. 6. The ultrasonic transducer according to claim 5, wherein the polarization process is a voltage application process or a corona discharge process. An ultrasonic probe comprising an ultrasonic transmission transducer and an ultrasonic reception transducer, comprising the organic piezoelectric film formed of the organic piezoelectric material according to claim 1. An ultrasonic probe using the ultrasonic transducer made as an ultrasonic receiving transducer. Ultrasound in which a means for generating an electrical signal and a plurality of transducers for receiving the electrical signal and transmitting an ultrasonic wave toward the subject and generating a reception signal corresponding to the reflected wave received from the subject are arranged In the ultrasonic medical image diagnostic apparatus, comprising: an ultrasonic probe; and an image processing unit that generates an image of the subject according to the reception signal generated by the ultrasonic probe. The ultrasonic medical image diagnostic apparatus according to claim 7, wherein the ultrasonic probe is the ultrasonic probe according to claim 7.

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