JP5493856B2 - Organic piezoelectric film, method for forming the same, ultrasonic transducer using the same, ultrasonic probe, and ultrasonic medical diagnostic imaging apparatus - Google Patents

Description

  The present invention relates to an organic piezoelectric film, a method for forming the same, an ultrasonic transducer using the organic piezoelectric film, an ultrasonic probe, and an ultrasonic medical image diagnostic apparatus.

  For details, for example, acoustic devices such as microphones and speaker diaphragms, various thermal sensors, pressure sensors, ultrasonic probes, vibration sensors that detect mutations in genes and proteins with high sensitivity, etc. The present invention relates to an organic piezoelectric film having high piezoelectricity that can be used to convert energy, a method for forming the same, and the like.

Conventionally, as a piezoelectric body, a so-called inorganic material in which a single crystal such as quartz, LiNbO ₃ , LiTaO ₃ , KNbO ₃ , a thin film such as ZnO or AlN, or a sintered body such as Pb (Zr, Ti) O ₃ is subjected to polarization treatment. Piezoelectric ceramics are widely used.

On the other hand, organic piezoelectric bodies using organic polymer substances such as polyvinylidene fluoride (PVDF) (also referred to as “piezoelectric polymer materials” or “polymer piezoelectric substances”) have been developed (for example, patent documents). 1). 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. The organic piezoelectric material is expected to be applied to a speaker, a microphone, an ultrasonic probe, a hydrophone, a vibration meter, a strain meter and the like because of the above characteristics.

  Examples of a method for forming an organic piezoelectric (piezoelectric resin) film include a diisocyanate compound such as 4,4′-diphenylmethane diisocyanate (MDI) and 4,4′-diaminodiphenylmethane (MDA). A so-called vapor deposition polymerization method in which such a diamine compound is evaporated at the same time to form a polyurea film is known (see, for example, Patent Documents 2 to 4).

  In the case of the method disclosed in Patent Document 2, since polyurea is formed by simultaneously evaporating two types of monomers, a diisocyanate compound and a diamine compound, the evaporation temperature of each monomer is different. There is a problem that the composition ratio of monomers in the formed polyurea film is different from the stoichiometric composition ratio, and it is necessary to set each monomer separately and deposit while controlling the temperature. there were. Depending on the combination of the diisocyanate compound and the diamine compound, the reactivity may not be expected. If the temperature of the substrate to be deposited is not adjusted appropriately, the polymerization does not proceed and the desired organic piezoelectric film cannot be obtained. . Furthermore, in vapor deposition polymerization, it takes time to form a thick film, requires a large vacuum facility, requires an apparatus for adjusting the substrate temperature, and requires a large amount of capital investment and manufacturing time. It becomes a big problem.

  On the other hand, in the vapor deposition polymerization method, the compound produced by vapor deposition is an oligomer of urea of about pentamer, and since the oligomer is subjected to polarization treatment, it is difficult to be oriented in terms of molecular mobility. It is difficult to orient all the urea bonds existing in the film, and it is considered that a proper organic piezoelectric film cannot be obtained.

  In addition, in the case of the method disclosed in Patent Document 3, since the polymerization can be performed while aligning the vapor deposition molecules by performing the vapor deposition polymerization and the polarization treatment separately, but simultaneously, the polymer formed Dipoles are oriented in the film, and a good organic piezoelectric film can be obtained. However, in order to perform the polarization treatment and the vapor deposition polymerization at the same time, a base material necessary for the polarization treatment is installed near the substrate on which the film is formed, so that the inside of the apparatus becomes complicated and the operability is lowered. In addition, the inside of the vapor deposition apparatus is contaminated with a deposit of monomer and needs to be frequently cleaned.

  In order to solve the above problems, a method for obtaining an organic piezoelectric film by thermal polymerization instead of vapor deposition polymerization as disclosed in Patent Document 4 has been found. In this method, a polymer containing a cross-linking agent having a large dipole is applied to a substrate, and thermal polymerization is performed while performing polarization treatment. A film can be made.

  However, in the above method, only the cross-linking agent having a structure having a large dipole in the cross-linking agent contained in the organic piezoelectric film is oriented and induces piezoelectricity, so that the piezoelectricity of the entire organic piezoelectric film is low. Moreover, it is necessary to prepare a cross-linking agent having a large dipole instead of a normal cross-linking agent, which requires a great deal of cost.

  By the way, an ultrasonic wave is generally referred to as a sound wave of 16000 Hz or higher, and can be examined non-destructively and harmlessly, so that it can be applied to various fields such as defect inspection and disease diagnosis. ing. For example, an ultrasonic diagnosis that scans the inside of a subject with ultrasound and images the internal state of the subject based on a reception signal generated from a reflected wave (echo) of the ultrasound from the inside of the subject. There is a device. In this ultrasonic diagnostic apparatus, an ultrasonic probe that transmits and receives ultrasonic waves to and from a subject is used. As this ultrasonic probe, a transducer that generates a received signal by receiving a reflected wave of an ultrasonic wave generated by a difference in acoustic impedance inside a subject is generated by mechanical vibration based on a transmission signal. An ultrasonic transmitting / receiving element configured to be provided is used.

  In recent years, harmonic imaging that forms an image of the internal state in the subject using the harmonic frequency component, not the frequency (fundamental frequency) component of the ultrasound transmitted from the ultrasound probe into the subject ( (Harmonic 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 is improved. (3) Since the sound pressure is small and the fluctuation of the sound pressure is small at a short distance, multiple reflections are suppressed. (4) Focus It has various advantages such as a greater depth speed compared to the case where the further attenuation is the same as the fundamental wave and the high frequency is the fundamental wave. This ultrasonic probe for harmonic imaging requires a wide frequency band from the frequency of the fundamental wave to the frequency of the harmonic, and its lower frequency range is used for transmission to transmit the fundamental wave. Is done. On the other hand, the frequency region on the high frequency side is used for reception for receiving harmonics (see, for example, Patent Document 5).

  The ultrasonic probe disclosed in Patent Document 5 receives an ultrasonic wave that is applied to a subject, transmits an ultrasonic wave into the subject, and reflects and returns within the subject. It is an acoustic probe. The ultrasonic probe transmits a fundamental wave composed of ultrasonic waves having a predetermined center frequency, which is composed of a plurality of arranged first piezoelectric elements having a predetermined first acoustic impedance, into the subject. , And a first piezoelectric layer responsible for receiving the fundamental wave of the ultrasonic waves reflected back within the subject. Further, a higher harmonic wave of ultrasonic waves reflected and returned from the subject, which includes a plurality of second piezoelectric elements arranged with a predetermined second acoustic impedance smaller than the first acoustic impedance. A second piezoelectric layer responsible for receiving waves is provided. The second piezoelectric layer is overlaid on the entire surface of the first piezoelectric layer on the side where the ultrasonic probe is applied to the subject. Therefore, the ultrasonic probe can transmit and receive ultrasonic waves in a wide frequency band with such a configuration.

The fundamental wave in harmonic imaging is preferably a sound wave having the narrowest possible bandwidth. An inorganic piezoelectric material is widely used as the piezoelectric material that bears this. On the other hand, a piezoelectric element that detects a received wave on the high frequency side requires a wider bandwidth sensitivity, and these inorganic materials are not suitable. As a piezoelectric element suitable for a high frequency and a wide band, an organic piezoelectric body using an organic polymer substance is known. However, the sensitivity is not sufficient, and a high frequency cannot be received with high sensitivity.
JP-A-6-216422 JP 7-258370 A Japanese Patent Laid-Open No. 5-31399 JP 2006-49418 A Japanese Patent Laid-Open No. 11-276478

  The present invention has been made in view of the above-described problems and situations, and the solution to the problem is formed using at least one diamine compound and at least one compound having two or more carbonyl groups or thiocarbonyl groups as raw materials. An organic piezoelectric film that is excellent in piezoelectricity and can be easily formed (manufactured) at low cost, and a method for forming the organic piezoelectric film.

  It is another object of the present invention to provide an ultrasonic transducer, an ultrasonic probe, and an ultrasonic medical image diagnostic apparatus that can receive high frequency with high sensitivity and are suitable for harmonic imaging technology.

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

  1. An organic piezoelectric film formed by thermal polymerization and polarization treatment using at least one diamine compound and at least one compound having two or more carbonyl groups or thiocarbonyl groups as raw materials, and an equivalent mixed solution of the raw materials An organic piezoelectric film formed on a substrate by applying thermal polymerization and polarization treatment simultaneously.

  2. 2. The at least one compound having two or more carbonyl groups is a dicarboxylic acid dihalide, a tetracarboxylic dianhydride, an anhydride of a carboxylic acid halide, or a diisocyanate compound. Organic piezoelectric film.

  3. 2. The organic piezoelectric film as described in 1 above, wherein the at least one compound having two or more thiocarbonyl groups is a diisothiocyanate compound.

  4). 4. The organic piezoelectric film according to any one of 1 to 3, wherein a compound constituting the organic piezoelectric film has an aromatic condensed ring structure.

  5. 5. The method for forming an organic piezoelectric film according to any one of 1 to 4, wherein a temperature in thermal polymerization is −50 to 250 ° C.

  6). 5. The method for forming an organic piezoelectric film according to any one of 1 to 4, wherein the polarization treatment method in the polarization treatment is by corona discharge, and the applied voltage is 0.5 to 2.0 MV / m. 6. The method of forming an organic piezoelectric film as described in 5 above.

  7). An ultrasonic vibrator using the organic piezoelectric film according to any one of 1 to 4 above.

  8). An ultrasonic probe comprising an ultrasonic transmission transducer and an ultrasonic reception transducer, wherein the ultrasonic transducer using the organic piezoelectric film according to any one of 1 to 4 is used as an ultrasonic probe. An ultrasonic probe comprising a transducer for receiving a sound wave.

  9. 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 8, wherein the ultrasonic probe is described above.

  An organic piezoelectric film formed by the above means of the present invention using at least one diamine compound and at least one compound having two or more carbonyl groups or thiocarbonyl groups as a raw material, having excellent piezoelectricity, and It is possible to provide an organic piezoelectric film that can be easily formed (manufactured) at low cost and a method for forming the same.

  Furthermore, it is possible to provide an ultrasonic transducer, an ultrasonic probe, and an ultrasonic medical image diagnostic apparatus that can receive high frequency with high sensitivity and are suitable for the harmonic imaging technique.

Conceptual diagram showing the configuration of the main part of an ultrasonic medical diagnostic imaging apparatus

Explanation of symbols

1 Receiving piezoelectric material (film)
2 Support 3 Piezoelectric material for transmission (film)
4 Backing layer 5 Electrode 6 Acoustic lens

  The organic piezoelectric film of the present invention is an organic piezoelectric film (polyamide) formed by thermal polymerization and polarization treatment using at least one diamine compound and at least one compound having two or more carbonyl groups or thiocarbonyl groups as raw materials. , Polyamideimide, polyimide, polyurea, etc. as a main component), which is formed by applying an equivalent mixed solution of the raw materials on a substrate and simultaneously performing thermal polymerization and polarization treatment. And This feature is a technical feature common to the inventions according to claims 1 to 9.

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

(Diamine compound)
As the diamine compound according to the present invention, various conventionally known diamine compounds as raw materials for functional polymers and organic piezoelectric materials, or positional isomers in which amino groups of these compounds are bonded to different places are used. A compound having a sterically hindered substituent at the α-position, β-position, or γ-position of the amino group, or a diamine compound has an electron-withdrawing substituent, and the nucleophilicity of the amino group is Reduced compounds are preferred. Of course, it is needless to say that a compound having an electron-withdrawing substituent having a large steric hindrance at the α-position, β-position and γ-position of the amino group is also preferable.

  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 include, but are not limited to, the following compounds.

  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-t-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), 4,4′-diaminodiphenyl ether, 3,4′-diaminodiphenyl ether, 4,4′-diaminooctafluorodiphenyl ether, 4,4′-diaminodiphenyl sulfide, 4,4′-diaminodiphenyl disulfide, bis (4-aminophenyl) ) Sulfone, bis (3-aminophenyl) sulfone, bis (3-amino-4-hydro) Ciphenyl) sulfone, bis (4-aminophenyl) 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-oxadiazole, neopentyl glycol bis (4-aminophenyl) ether, 4,4′-diaminostilbene, α, α′-bis (4-aminophenyl) -1,4-diisopropyl Benzene, 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-diaminofluorene, 3,6-diaminofluorene, 9 , 9-bis (4-aminophenyl) fluorene, 9,9-bis (4-amino-3-methylphenyl) fluor Len, 9,9-bis (3-amino-4-hydroxyphenyl) fluorene, 9,9-bis (4-amino-3-fluorophenyl) fluorene, 9,9-bis (4-amino-3-chlorophenyl) Fluorene, 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, and the like.

(Compound having two or more carbonyl groups or thiocarbonyl groups)
As the “compound having two or more carbonyl groups or thiocarbonyl groups” according to the present invention, compounds having two or more conventionally known various carbonyl groups or thiocarbonyl groups as raw materials for functional polymers and organic piezoelectric materials, Alternatively, regioisomers in which the carbonyl group or thiocarbonyl group of these compounds are bonded to different positions can be used, but dicarboxylic acid dihalide, tetracarboxylic dianhydride, carboxylic acid halide anhydride, diisocyanate A narate compound, a diisothiocyanate compound and the like are preferable. Hereinafter, each compound will be described in detail.

<Tetracarboxylic dianhydride>
Tetracarboxylic dianhydride includes a compound having a highly sterically hindered substituent at the α-position, β-position, and γ-position of the carboxyl group, or an electron-donating substituent in the tetracarboxylic dianhydride. A compound in which the electrophilicity of the carbonyl group is reduced is preferred. Of course, it is needless to say that compounds having electron-donating substituents having a large steric hindrance at the α-position, β-position and γ-position of the carboxyl group are also preferred.

  Specific examples include, but are not limited to, the following compounds.

  Pyromellitic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 3,3 ′, 4,4′-biphenyl Tetracarboxylic dianhydride, 1,2,5,6-naphthalene tetracarboxylic dianhydride, 2,2 ′, 3,3′-biphenyltetracarboxylic dianhydride, 3,3 ′, 4,4 ′ -Benzophenonetetracarboxylic dianhydride, 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, bis (3,4- Dicarboxyphenyl) propane dianhydride, 1,1-bis (2,3-dicarboxyphenyl) ethane dianhydride, 1,1-bis (3,4-dicarboxyphenyl) ethane dianhydride, bis (2 , 3-Dicarboxy Enyl) methane dianhydride, bis (3,4-dicarboxyphenyl) ethane dianhydride, oxydiphthalic dianhydride, bis (3,4-dicarboxyphenyl) sulfone dianhydride, p-phenylenebis (trimerit Acid monoester acid anhydride), 4,4′-oxydiphthalic acid anhydride, 3,3 ′, 4,4′-diphenylsulfonetetracarboxylic dianhydride, ethylenebis (trimellitic acid monoester acid anhydride), 1,2,3,4-cyclopentanetetracarboxylic dianhydride, bisphenol A bis (trimellitic acid monoester acid anhydride) and the like.

<Dicarboxylic acid dihalide>
The dicarboxylic acid dihalide is a compound having a substituent having a large steric hindrance at the α-position, β-position or γ-position of the carbonyl group, or the dicarboxylic acid dihalide has an electron-donating substituent, and the carbonyl group Compounds with reduced electrophilicity are preferred. A compound having an electron-donating substituent having a large steric hindrance at the α-position, β-position, and γ-position of the carbonyl group is also preferable.

  Specific examples include, but are not limited to, the following compounds.

  Phthalic acid dichloride, phthalic acid dibromide, methylphthalic acid dichlorides, ethylphthalic acid dichlorides, methoxyphthalic acid dichlorides, ethoxyphthalic acid dichlorides, chlorophthalic acid dichlorides, bromophthalic acid Dichlorides, isophthalic acid dichlorides, methylisophthalic acid dichlorides, ethylisophthalic acid dichlorides, methoxyisophthalic acid dichlorides, ethoxyisophthalic acid dichlorides, chloroisophthalic acid dichloride , Bromoisophthalic acid dichloride, terephthalic acid dichloride, methyl terephthalic acid dichloride, ethyl terephthalic acid dichloride, methoxyterephthalic acid dichloride, ethoxyterephthalic acid dichloride, chloroterephthalate Acid dichlorides, bromoterephthalic acid dichlorides, 2,2'-biphenyldicarboxylic acid dichloride, 4,4'-bifu Nyldicarboxylic acid dichloride, 4,4'-diphenyl ether dicarboxylic acid dichloride, 4,4'-diphenyl sulfide dicarboxylic acid dichloride, 4,4'-benzophenone dicarboxylic acid dichloride, 4,4'-diphenyl Sulfone dicarboxylic acid dichloride, 4,4′-diphenylmethane dicarboxylic acid dichloride, 2,2-bis (4-chloroformylphenyl) propane, 2,2-bis (4-chloroformylphenyl) -1, 1,1,3,3,3-hexafluoropropane, 1,4-naphthalenedicarboxylic acid dichloride, 2,3-naphthalenedicarboxylic acid dichloride, 2,6-naphthalenedicarboxylic acid dichloride, 2,6 Naphthalene dicarboxylic acid dibromide, etc.

<Acid anhydride of carboxylic acid halide>
As the carboxylic acid halide acid anhydride (carboxylic acid anhydride having a carboxylic acid halide structure) according to the present invention, a compound having a sterically hindered substituent at the α-position, β-position and γ-position of the carbonyl group Alternatively, a compound having an electron-donating substituent in a carboxylic acid anhydride having a structure of a carboxylic acid halide and having reduced electrophilicity of a carbonyl group is preferable. A compound having an electron-donating substituent having a large steric hindrance at the α-position, β-position, and γ-position of the carbonyl group is also preferable.

  Specific examples include, but are not limited to, the following compounds.

  4- (chloroformyl) phthalic anhydride, 4- (chloroformyl) -3-methylphthalic anhydride, 4- (chloroformyl) -5-methylphthalic anhydride, 4- (chloroformyl)- 3,5-dimethylphthalic anhydride, and the like.

<Diisocyanate compound>
As the diisocyanate compound according to the present invention, a compound having a substituent having a large steric hindrance at the α-position, β-position, and γ-position of the isocyanate group, or a diisocyanate compound has an electron-donating substituent. A compound having a reduced electrophilicity of an isocyanate group is preferred. A compound having an electron-donating substituent having a large steric hindrance at the α-position, β-position, and γ-position of the isocyanate group is also preferable.

  Specific examples include, but are not limited to, the following compounds.

  4,4′-diphenylmethane diisocyanate (MDI), 4,4′-methylenebis (2,6-dimethylphenylisocyanate), 4,4′-methylenebis (2,6-diethylphenylisocyanate), 4,4 '-Methylenebis (2,6-di-t-butylphenylisocyanate), 4,4'-methylenebis (2,6-dicyclohexylphenylisocyanate), 4,4'-methylenebis (2-methylphenylisocyanate), 4,4'-methylenebis (2-ethylphenyl isocyanate), 4,4'-methylenebis (2-tert-butylphenyl isocyanate), 4,4'-methylenebis (2-cyclohexylphenyl isocyanate), 4,4 '-Methylenebis (3,5-dimethylphenyl isocyanate), 4,4'-methyle Bis (2,3-dimethylphenyl isocyanate), 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) Nato), 4,4′-methylenebis (2-chlorophenyl isocyanate), 4,4′-methylenebis (2,3-dibromophenyl isocyanate), m-xylylene diisocyanate, 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 diisocyanate (2,6-TDI), 1,3- Bis (2-isocyanato-2-propyl) benzene, 1,3-bis (isocyanatomethyl) cyclohexane, dicyclohexylmethane-4,4′-diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, trimethylhexa Methylene diisocyanate, and the like.

<Diisothiocyanate compound>
Examples of the diisothiocyanate compound according to the present invention include compounds having a highly sterically hindered substituent at the α-position, β-position and γ-position of the isothiocyanate group, or an electron-donating substituent in the diisothiocyanate compound. A compound in which the electrophilicity of the isothiocyanate group is reduced is preferable. A compound having an electron-donating substituent having a large steric hindrance at the α-position, β-position, and γ-position of the isothiocyanate group is also preferable.

  Specific examples include, but are not limited to, the following compounds.

  4,4′-diphenylmethane diisothiocyanate, 4,4′-methylenebis (2,6-diethylphenylisothiocyanate), 4,4′-methylenebis (2,6-di-t-butylphenylisothiocyanate) 1,3-bis (isothiocyanatomethyl) cyclohexane, 1,3-propanediisothiocyanate, 1,5-pentanediisothiocyanate, 1,7-heptanediisothiocyanate, 1,9-nonane Isothiocyanate, 1,11-undecanediisothiocyanate, and the like.

<Aromatic condensed ring structure>
In the present invention, in order to improve the orientation of the organic piezoelectric film, the compound constituting the organic piezoelectric film preferably has an aromatic condensed ring structure as a partial structure.

  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 (ACR4).

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, Chlorooxy group), 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 group (Aminocarbonyl group, methylaminocarbonyl group, dimethylaminocarbonyl group, propylaminocarbonyl group, pentylaminocarbonyl group, cyclohexylaminocarbonyl group, phenylaminocarbonyl Group, 2-pyridylaminocarbonyl group), a carboxyl group, and a hydroxyl group. Preferred is a hydrogen atom, hydroxyl group, carboxyl group, alkoxy group, acyloxy group or alkyl group, more preferred is a hydrogen atom, alkyl group, hydroxyl group or acyloxy group, and particularly preferred is a hydrogen atom or alkyl group. 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 formula (ACR3), X ₃ represents a nitrogen atom or N ⁺ -R _33, R ₃₃ represents an alkyl group or an aryl group. When X ₃ is N +, it may have a counter ion for neutralizing the charge, and examples of the counter ion include Cl ⁻ , Br ⁻ , I ⁻ and BF ₄ ⁻ .

  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.

  As a means for introducing the aromatic condensed ring structure, a substituted or unsubstituted diamine or diisocyanate having a condensed ring structure may be added as a third component during polymerization, or the condensed ring structure may be Means (method) such as polymerization of the compound of the present invention possessed can be mentioned.

  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 It may be substituted with a heteroaryl group or the like, and R ₁₃ represents a carbonyl group, a sulfonyl group, a thiocarbonyl group, or a sulfone group, and these substituents bind a 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.)

(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.)

(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.)
Preferable examples include compounds represented by the general formulas (4) to (6) or derivatives of these compounds.

<< Compound Represented by Formula (4) >>
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.

<< Compound Represented by Formula (5) >>
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.

<< Compound Represented by Formula (6) >>
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.

(solvent)
Examples of the solvent that can be used in the present invention include amide solvents such as dimethyl sulfoxide, dimethylformamide, dimethylacetamide, and N-methylpyrrolidone, which are aprotic solvents, tetrahydrofuran, acetone, methyl ethyl ketone, ethyl acetate, methylene chloride, and chloroform. , Toluene, hexane and the like. There is no particular limitation as long as the solvent can dissolve both the diamine compound and the compound having two or more carbonyl groups or thiocarbonyl groups.

(Organic piezoelectric film)
In the present invention, as a preferable organic piezoelectric film, an organic piezoelectric film containing a urea resin formed by the following combination of the raw materials can be exemplified.

  4,4′-diaminodiphenylmethane / 3,3′-dimethyldiphenyl-4,4′-diisocyanate, 4,4′-diaminodiphenylmethane / o-dianisidine diisocyanate, 4,4′-diaminodiphenylmethane / methylenebis (4-isocyanato-2-methylbenzene), 4,4′-diaminodiphenylmethane / 4,4′-diphenylmethane diisocyanate (MDI), 4,4′-diaminodiphenylmethane / 2,4-toluene diisocyanate ( 2,4-TDI), 4,4′-diaminodiphenylmethane / 2,6-toluene diisocyanate (2,6-TDI), 4,4′-diaminodiphenylmethane / bis (4-isocyanatophenyl) ether, 4,4'-Diaminodiphenylmethane / p-phenylene diisocyanate 4,4′-diaminodiphenylmethane / 1,5-naphthalene diisocyanate, 4,4′-diaminodiphenyl ether / 3,3′-dimethyldiphenyl-4,4′-diisocyanate, 4,4′-diaminodiphenyl ether / O-dianisidine diisocyanate, 4,4′-diaminodiphenyl ether / methylenebis (4-isocyanate-2-methylbenzene), 4,4′-diaminodiphenyl ether / 4,4′-diphenylmethane diisocyanate (MDI) 4,4′-diaminodiphenyl ether / 2,4-toluene diisocyanate (2,4-TDI), 4,4′-diaminodiphenyl ether / 2,6-toluene diisocyanate (2,6-TDI), 4 , 4'-Diaminodiphenyl ether / bis (4-isocyanate Tophenyl) ether, 4,4′-diaminodiphenyl ether / p-phenylene diisocyanate, 4,4′-diaminodiphenyl ether / 1,5-naphthalenediisocyanate, 4,4′-diaminodiphenyl ether / 1,3-bis ( Isocyanatomethyl) benzene, 4,4′-diamino-3,3′-dimethyldiphenylmethane / 3,3′-dimethyldiphenyl-4,4′-diisocyanate 4,4′-diamino-3,3′-dimethyl Diphenylmethane / o-dianisidine diisocyanate, 4,4′-diamino-3,3′-dimethyldiphenylmethane / methylenebis (4-isocyanato-2-methylbenzene), 4,4′-diamino-3,3′- Dimethyldiphenylmethane / 4,4'-diphenylmethane diisocyanate ( MDI), 4,4′-diamino-3,3′-dimethyldiphenylmethane / 2,4-toluene diisocyanate (2,4-TDI), 4,4′-diamino-3,3′-dimethyldiphenylmethane / 2 , 6-Toluene diisocyanate (2,6-TDI), 4,4′-diamino-3,3′-dimethyldiphenylmethane / bis (4-isocyanatophenyl) ether, 4,4′-diamino-3, 3′-dimethyldiphenylmethane / p-phenylenediisocyanate, 4,4′-diamino-3,3′-dimethyldiphenylmethane / 1,5-naphthalenediisocyanate, 3,3′-dimethoxy-4,4′-diamino Biphenyl / 3,3′-dimethyldiphenyl-4,4′-diisocyanate, 3,3′-dimethoxy-4,4′-diaminobiphenyl o-dianisidine diisocyanate, 3,3′-dimethoxy-4,4′-diaminobiphenyl / methylenebis (4-isocyanato-2-methylbenzene), 3,3′-dimethoxy-4,4′-diaminobiphenyl / 4,4′-diphenylmethane diisocyanate (MDI), 3,3′-dimethoxy-4,4′-diaminobiphenyl / 2,4-toluene diisocyanate (2,4-TDI), 3,3′- Dimethoxy-4,4′-diaminobiphenyl / 2,6-toluene diisocyanate (2,6-TDI), 3,3′-dimethoxy-4,4′-diaminobiphenyl / bis (4-isocyanatophenyl) Ether, 3,3′-dimethoxy-4,4′-diaminobiphenyl / p-phenylene diisocyanate, 3,3′-dimethoxy-4,4 -Diaminobiphenyl / 1,5-naphthalenediisocyanate, 3,3'-dimethyl-4,4'-diaminobiphenyl / 3,3'-dimethyldiphenyl-4,4'-diisocyanate, 3,3'- Dimethyl-4,4′-diaminobiphenyl / o-dianisidine diisocyanate, 3,3′-dimethyl-4,4′-diaminobiphenyl / methylenebis (4-isocyanato-2-methylbenzene), 3,3 ′ -Dimethyl-4,4'-diaminobiphenyl / 4,4'-diphenylmethane diisocyanate (MDI), 3,3'-dimethyl-4,4'-diaminobiphenyl / 2,4-toluene diisocyanate (2, 4-TDI), 3,3′-dimethyl-4,4′-diaminobiphenyl / 2,6-toluene diisocyanate (2,6-TDI), 3 3,3′-dimethyl-4,4′-diaminobiphenyl / bis (4-isocyanatophenyl) ether, 3,3′-dimethyl-4,4′-diaminobiphenyl / p-phenylenediisocyanate, 3,3 '-Dimethyl-4,4'-diaminobiphenyl / 1,5-naphthalene diisocyanate, 4,4'-methylene-bis (2-chloroaniline) / 3,3'-dimethyldiphenyl-4,4'-di Isocyanate, 4,4'-methylene-bis (2-chloroaniline) / o-dianisidine diisocyanate, 4,4'-methylene-bis (2-chloroaniline) / methylenebis (4-isocyanato-2- Methylbenzene), 4,4′-methylene-bis (2-chloroaniline) / 4,4′-diphenylmethane diisocyanate (MDI), 4,4′-me Ren-bis (2-chloroaniline) / 2,4-toluene diisocyanate (2,4-TDI), 4,4′-methylene-bis (2-chloroaniline) / 2,6-toluene diisocyanate ( 2,6-TDI), 4,4'-methylene-bis (2-chloroaniline) / bis (4-isocyanatophenyl) ether, 4,4'-methylene-bis (2-chloroaniline) / p- Phenylene diisocyanate, 4,4′-methylene-bis (2-chloroaniline) / 1,5-naphthalene diisocyanate, 1,3-diamino-5-cyanobenzene / 2,6-naphthalene diisocyanate, 4 , 4′-diaminodiphenylmethane / pyromellitic dianhydride, 1,5-diaminonaphthalene / terephthalic acid dichloride, 4,4′-diaminodiphenyl ether / -(Chloroformyl) -phthalic anhydride, 4,4'-methylenebis (2,6-dimethylaniline) / 4,4'-methylenebis (2,6-diethylphenyl isocyanate), 4,4'-methylenebis (2,6-di-t-butylaniline) / 4,4′-diphenylmethane diisothiocyanate and the like.

  The organic piezoelectric film of the present invention may contain an additive (compound) other than the resin depending on the purpose.

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

Further, it may be formed on a multilayer piezoelectric element. As a method of using a multilayer for stacking piezoelectric elements, there is a method in which the organic piezoelectric film of the present invention is superposed on a ceramic piezoelectric element via an electrode. PZT is used as the ceramic piezoelectric element, but in recent years, one containing no lead has been recommended. PZT is preferably within the range of the formula Pb (Zr _{1 −X} Ti _X ) O ₃ (0.47 ≦ X ≦ 1). As deleading, natural or artificial quartz, lithium niobate (LiNbO ₃ ), potassium niobium tantalate [K (Ta, Nb) O ₃ ], barium titanate (BaTiO ₃ ), lithium tantalate (LiTaO ₃ ), or strontium titanate (SrTiO ₃ ). The composition of various ceramic materials can be selected as appropriate in terms of performance.

(Method of forming organic piezoelectric film)
The organic piezoelectric film forming method of the present invention forms an organic piezoelectric film by thermal polymerization and polarization treatment using at least one diamine compound and at least one compound having two or more carbonyl groups or thiocarbonyl groups as raw materials. An organic piezoelectric film is formed by applying an equivalent mixed solution of the raw materials on a substrate and forming the organic piezoelectric film while simultaneously performing thermal polymerization and polarization treatment.

  In this forming method, as a preferred embodiment, an equivalent mixed solution of raw materials is applied on a substrate, dried to some extent under reduced pressure conditions (after removing a predetermined amount of solvent), heated, and simultaneously subjected to thermal polymerization and polarization treatment. A method of forming an organic piezoelectric film while proceeding is preferable.

  In this invention, it is preferable that the temperature at the time of making a thermal polymerization and a polarization process advance simultaneously is -50-250 degreeC. More preferably, it is -50-200 degreeC. In some cases, it is also preferable to change the temperature in the middle of gradually increasing the temperature or gradually decreasing the temperature within the above-mentioned temperature range during the simultaneous progress of the thermal polymerization and the polarization treatment.

  That is, a mode is preferred in which polymerization is started when the temperature is −50 ° C. or higher, and by gradually increasing the temperature, the state of being easily polarized can be maintained while compensating for the deterioration of molecular motion accompanying the increase in molecular weight. . By setting it as such an aspect, it can prevent that a board | substrate deteriorates. Moreover, depolymerization of a molecule | numerator can be suppressed because it is 250 degrees C or less.

  It should be noted that by setting the temperature to −50 ° C., the reactivity of the raw material can be lowered from the room temperature, and the reactivity of the diamine compound and the compound having two or more carbonyl groups or thiocarbonyl groups itself is lowered. Means, for example, a step of modification of the amino group with a protecting group is not required.

  The “equivalent mixed solution” in the present invention is supplied from a compound having a total number of amino groups supplied from a diamine compound and two or more carbonyl groups or thiocarbonyl groups, and directly bonded to a nitrogen atom, an oxygen atom, or a halogen atom. In principle, it means a solution dissolved in a solvent so that the total number of carbonyl groups or thiocarbonyl groups to be equalized. However, the mixing ratio is not limited to 1: 1, and a substantially equivalent mixed solution may be used as long as the ratio is 1: 0.9 to 1: 1.1.

  In addition, as long as the requirements of the above “equivalent mixed solution” are satisfied, the mixed solution used in the present invention may contain two or more diamine compounds and two or more compounds each having two or more carbonyl groups or thiocarbonyl groups. Moreover, you may contain compounds other than these compounds.

(Polarization treatment)
As a polarization treatment method in the polarization treatment according to the present invention, various conventionally known methods can be applied, but a corona discharge treatment method is preferable.

The corona discharge treatment can be performed using a commercially available high-voltage power source and an electrode device.
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 in absolute value, 1 μA to 1 mA in current, and the distance between the electrodes is 1 10 cm is preferable, 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 addition, since heating is performed during corona discharge, it is necessary to install a heater via an insulator under the electrode in contact with the substrate manufactured according to the present invention.

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

(Ultrasonic transducer)
The ultrasonic transducer according to the present invention is characterized by using the organic piezoelectric film 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 converge 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>
The transducer for ultrasonic reception according to the present invention is a transducer used in a probe for an ultrasonic medical diagnostic imaging apparatus, and the organic piezoelectric film of the present invention is used as a piezoelectric material constituting the transducer. It is characterized by.

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 permittivity is adjusted by adjusting the number, composition, polymerization degree, etc. of polar functional groups such as CF ₂ groups and CN groups, and the above-mentioned polarization treatment, which the compound constituting the organic piezoelectric film has. Can do.

<Transmitter for ultrasonic transmission>
The ultrasonic transmission vibrator according to the present invention is preferably composed of a piezoelectric material having an appropriate relative dielectric constant in relation to the ultrasonic reception vibrator. 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.

Examples of the inorganic material include quartz, lithium niobate (LiNbO ₃ ), potassium niobate tantalate [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. Incidentally, PZT is _{Pb (Zr 1 - n Ti n} ) O 3 (0.47 ≦ n ≦ 1) is preferred.

<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. 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 insulating material is formed to a thickness of 1 to 10 μm by sputtering 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)
The ultrasonic probe according to the present invention is a probe for an ultrasonic diagnostic imaging apparatus including an ultrasonic transmission transducer and an ultrasonic reception transducer. The ultrasonic receiving vibrator according to the above 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 FIG.

  FIG. 1 is a conceptual diagram showing a configuration of a main part of an ultrasonic medical image diagnostic apparatus according to an 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 wave 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, this invention is not limited to these. A compound having two or more carbonyl groups is simply referred to as “carbonyl compound”. Similarly, a compound having two or more thiocarbonyl groups is simply referred to as “thiocarbonyl compound”.

Example 1
<< Preparation of Equivalent Mixture 1 of Diamine Compound and Carbonyl Compound >>
After adding 100 ml of acetone to a 300 ml flask and adjusting the temperature to −30 ° C., 9.9 g of 4,4′-diaminodiphenylmethane and 10.9 g of pyromellitic dianhydride were added, and the mixture was stirred for 5 minutes. Was prepared.

<< Preparation of Equivalent Mixture 2 of Diamine Compound and Carbonyl Compound >>
Add 100 ml of acetone to a 300 ml flask and adjust the temperature to −50 ° C., then add 7.9 g of 1,5-diaminonaphthalene and 10.2 g of terephthalic acid dichloride and stir for 5 minutes to prepare an equivalent mixture 2 did.

<< Preparation of Equivalent Mixture 3 of Diamine Compound and Carbonyl Compound >>
Add 100 ml of acetone to a 300 ml flask and adjust the temperature to −50 ° C., then add 10.0 g of 4,4′-diaminodiphenyl ether and 10.5 g of 4- (chloroformyl) -phthalic anhydride for 5 minutes. Stir to prepare an equivalent mixture 3.

<< Preparation of Equivalent Mixture 4 of Diamine Compound and Carbonyl Compound >>
After adding 100 ml of acetone to a 300 ml flask and adjusting the temperature to −20 ° C., 12.7 g of 4,4′-methylenebis (2,6-dimethylaniline) and 4,4′-methylenebis (2,6-diethylphenyl) (Isocyanate) 18.1 g was added and stirred for 5 minutes to prepare an equivalent mixture 4.

<< Preparation of Equivalent Mixture 5 of Diamine Compound and Thiocarbonyl Compound >>
After adding 100 ml of acetone to a 300 ml flask and adjusting the temperature to −30 ° C., 23.7 g of 4,4′-methylenebis (2,6-di-t-butylaniline) and 4,4′-diphenylmethane diisothiocyanate 14.1 g of natto was added and stirred for 5 minutes to prepare an equivalent mixture 5.

<< Preparation of substrate coated with equivalent mixture >>
The equivalent mixtures 1 to 5 of the diisocyanate compound and the diamine compound were applied on the aluminum electrode of a polyimide substrate having a thickness of 25 μm on which an aluminum electrode was applied by vapor deposition so as to have a thickness of 5 μm on the dry pressure film. These equivalent mixed coating films of diamine compound and carbonyl compound were dried under reduced pressure at 5 kPa for 30 minutes while maintaining the temperature at which each equivalent mixture was prepared, to obtain equivalent mixed films 1 to 5 formed on the substrate.

<< Preparation of polarization-treated film >>
In order to allow thermal polymerization and polarization treatment to proceed simultaneously, the equivalent mixed films 1 to 5 are heated to a thermal polymerization heating temperature shown in Tables 1 and 2 at a rate of 5 ° C./min, respectively. After the stagnation of time, it was naturally cooled to 25 ° C. During this time, using a high voltage power supply device HARb-20R60 (manufactured by Matsusada Precision Co., Ltd.) and a needle-like electrode, discharge polarization treatment was performed with the polarization treatment applied electric field described in Tables 1 and 2, and then the obtained organic piezoelectric film was obtained. An aluminum electrode was applied to the surface on the body side by vapor deposition, and organic piezoelectric films 1 to 5 were obtained in order.

  In the production of the organic piezoelectric films 6 to 15, under the conditions of Tables 1 and 2, << Preparation of an equivalent mixture of a diamine compound and a carbonyl compound >>, << Preparation of a substrate coated with an equivalent mixture >>, << Polarized film It was produced in the same manner as that described above.

<< Production of Comparative Example 1 >>
The above-mentioned polyimide substrate is mounted in a vacuum processing chamber, and 4,4′-methylenebis (2,6-dimethylaniline) and 4,4′-methylenebis (2,6-diethylphenyl isocyanate) are subjected to vapor deposition polymerization to 5 μm ( Vapor deposition was performed to a film thickness of 50000 mm. The conditions at this time were 100 ± 3 ° C. for the diamine compound, 70 ± 3 ° C. for the carbonyl compound, 25 ° C. for the substrate temperature, and 1.0 × 10 ⁻³ Pa in the vapor deposition chamber. Next, this film was taken out and subjected to discharge polarization treatment in an electric field of 1.0 MV / m using the above-described high-voltage power supply device and needle electrode at 180 ° C. for 10 minutes. A comparative film 1 was obtained by applying an aluminum electrode to the surface by vapor deposition.

  Moreover, in preparation of the comparative example 2, it produced similarly to << preparation of the comparative example 1 >> under the conditions of Tables 1 and 2.

<< Production of Comparative Example 3 >>
The equivalent mixed film 4 was heated up to 150 ° C. at a rate of 5 ° C./minute, stagnated for 10 minutes, and then naturally cooled to 25 ° C. to obtain a heat-treated film. Thereafter, the temperature was raised again to 150 ° C. at a rate of 5 ° C./min, and after 10 minutes of stagnation, naturally cooled to 25 ° C. During this time, discharge polarization treatment was performed in an electric field of 1.0 MV / m using the above-described high-voltage power supply device and needle-like electrode, and then an aluminum electrode was applied by vapor deposition on the surface of the obtained film on the side of the organic piezoelectric material. 3 was obtained.

<< Evaluation of produced film >>
The piezoelectric properties of the obtained organic piezoelectric films 1 to 15 and comparative films 1 to 3 were measured with Rheograph Solid (manufactured by Toyo Seiki Co., Ltd.).

  The evaluation results are shown in Tables 1 and 2 as relative values when Comparative Example-1 is taken as 100.

  As is apparent from the results shown in Tables 1 and 2, it can be seen that in the examples according to the present invention, the piezoelectricity is superior to the comparative examples.

  That is, if the above-described method for forming an organic piezoelectric film is also taken into consideration, an organic piezoelectric body formed by using the diamine compound and a compound having two or more carbonyl groups or thiocarbonyl groups as raw materials according to the means of the present invention. It can be seen that there can be provided an organic piezoelectric film that is excellent in piezoelectricity and can be easily formed (manufactured) at low cost, and a method for forming the same.

Example 2
(Preparation and evaluation of ultrasonic 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 ) Bi _4.01 Ti Weighed to 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 the fine 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.

  In addition, as a comparative example, the ultrasonic wave except that the receiving laminated vibrator using only the organic piezoelectric film of Comparative Example-1 was laminated on the receiving laminated vibrator instead of the receiving laminated vibrator. A probe similar to the probe was produced.

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

As for the reception sensitivity, a fundamental frequency f _{1 of} 5 MHz was transmitted, and a reception relative sensitivity of 10 MHz as the reception second harmonic f ₂ , 15 MHz as the third harmonic, and 20 MHz as the fourth harmonic was obtained. 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.

Claims (9)

And at least one diamine compound, an organic piezoelectric film formed by the thermal polymerization and polarization treatment is used as a raw material and at least one compound having a carbonyl group or a thiocarbonyl group two or more equivalents mixing of the raw materials It is formed by applying a solution on a substrate and simultaneously performing thermal polymerization and polarization treatment .
An organic piezoelectric film, wherein the compound constituting the organic piezoelectric film has an aromatic fused ring structure . At least one compound having the carbonyl group two or more,請Motomeko 1 to dicarboxylic acid dihalide, a tetracarboxylic acid dianhydride, wherein the anhydride of a carboxylic acid halide, or a diisocyanate compound The organic piezoelectric film described in 1. Wherein the at least one compound having two or more thio carbonyl group, an organic piezoelectric film according to請Motomeko 1, characterized in that a diisothiocyanate compound.   A method for producing an organic piezoelectric film formed by thermal polymerization and polarization treatment using at least one diamine compound and at least one compound having two or more carbonyl groups or thiocarbonyl groups as raw materials,
  Applying an equivalent mixed solution of the raw materials on a substrate, and simultaneously performing thermal polymerization and polarization treatment;
  A method for producing an organic piezoelectric film, wherein the compound constituting the organic piezoelectric film has an aromatic condensed ring structure. The method for producing an organic piezoelectric film according to claim 4, wherein a temperature in the thermal polymerization is −50 to 250 ° C. The polarization processing method in polarization treatment is due to corona discharge, a method of manufacturing an organic piezoelectric film according to請Motomeko 4, wherein the applied voltage is 0.5~2.0MV / m. Ultrasonic transducer, characterized in that an organic piezoelectric film according to any one of the請Motomeko 1-3. An ultrasound probe comprising an ultrasonic transmitting oscillator and an ultrasonic receiving transducer, the ultrasonic transducer using the organic piezoelectric film according to any one of the請Motomeko 1-3 ultrasound probe, characterized by comprising as the ultrasonic receiving vibrator. 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. but ultrasonic medical image diagnostic apparatus, characterized in that the ultrasonic probe according to請Motomeko 8.