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DESCRIPTION JP2008036202

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DESCRIPTION JP2008036202
An object of the present invention is to use an electrode, an organic piezoelectric material, and a
fluorine-based polymer material as an organic piezoelectric material in multilayer composite
formation of an inorganic piezoelectric material, which is used for an ultrasonic probe of an
ultrasonic diagnostic apparatus. An organic piezoelectric material excellent in dielectric constant
and piezoelectricity, and a method of manufacturing the same, although it is possible to improve
the adhesion failure and improve the durability of transmission and reception as a piezoelectric
material of an ultrasonic probe. It is to provide. Another object of the present invention is to
provide a low cost organic piezoelectric material which does not use vapor deposition or CVD
equipment by using the fine particle dispersion technology, and a method of manufacturing the
same. A fluorine-based polymer material, which is a fluorine-based piezoelectric material, is
dispersed in fine particles in a polymer material matrix of a non-fluorine-based piezoelectric
material, coated or molded, and subjected to polarization treatment. Piezoelectric material. 【
Selection chart】 None
Piezoelectric material, ultrasonic probe, method of manufacturing piezoelectric material, and
method of manufacturing ultrasonic probe
[0001]
The present invention relates to a piezoelectric material, an ultrasonic probe, a method of
manufacturing a piezoelectric material, and a method of manufacturing an ultrasonic probe, and
in particular, a piezoelectric material particularly suitable for medical diagnosis with high
sensitivity, ultrasonic waves The present invention relates to a probe, a method of manufacturing
a piezoelectric material, and a method of manufacturing an ultrasonic probe.
14-04-2019
1
[0002]
Piezoelectric materials are used for actuators that control minute movements of machines and
for transmitting and receiving ultrasonic waves.
Ultrasound diagnostic devices that use ultrasound transmission and reception are used for
medical examinations that avoid exposure because X-rays are not used, especially in medical
applications. An ultrasonic diagnostic apparatus is a medical imaging device that non-invasively
obtains a tomogram of soft tissue in a living body from a body surface by an ultrasonic pulse
reflection method. The blood flow imaging is possible by applying the Doppler effect, and the
precise analysis of reflected wave image analysis includes cardiovascular system (heart coronary
artery), digestive system (gastrointestinal), internal medicine system (liver, pancreas, spleen),
urology It is widely used in the system (kidney, bladder) and obstetrics and gynecology. An
ultrasonic probe used in such a medical ultrasonic diagnostic apparatus generally utilizes the
piezoelectric effect of an inorganic piezoelectric element in order to transmit and receive
ultrasonic waves with high sensitivity and high resolution.
[0003]
Furthermore, in order to improve sensitivity, the piezoelectric inorganic element is laminated to
make it an ultrasonic transmitting / receiving element (see Patent Document 1), the apparent
impedance is reduced, and the electrical matching condition with the drive circuit is improved. It
is performed to increase the electric field strength to generate a large distortion to improve the
transmission sensitivity. However, although the transmission sensitivity increases in accordance
with the number of layers in the laminated structure, the reception sensitivity is inversely
proportional to the number of layers, which is disadvantageous for forming a harmonic image.
[0004]
Therefore, a wide-band organic piezoelectric element mainly composed of vinylidene fluoride has
attracted attention (see Patent Document 1). However, a resin obtained by polymerizing a
monomer solution to be a polymer resin using an initiator is further added After that, a process
of uniaxially or biaxially stretching and polarization treatment to obtain piezoelectric
performance is required, and the equipment cost is increased.
[0005]
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2
Then, the method of vapor-depositing the monomer of patent document 2 in a vacuum, making it
vapor-deposit and superpose | polymerize was proposed (refer patent document 2).
However, when two or more kinds of monomers are evaporated, or when the vapor pressures of
the monomers are different, evaporation is carried out by setting each suitable temperature, or a
polymer having a desired monomer composition can not be obtained. Was. Moreover, even if it
vapor-deposited, superposition | polymerization did not advance and the technique for advancing
superposition | polymerization was needed. Although a technique of performing plasma
treatment has been proposed as a technique for promoting polymerization (see Patent Document
3), there is a drawback that the cost of equipment becomes high. JP-A-7-74407 JP-A-2001261867 JP-A-2002-275266
[0006]
The present invention has been made in view of the above problems, and an object of the present
invention is to use an electrode, an organic piezoelectric material, and an organic piezoelectric
composite material of an inorganic piezoelectric material for use in an ultrasonic probe of an
ultrasonic diagnostic apparatus. Although it is possible to improve the adhesion failure of a
fluorine-based polymer material as a piezoelectric material and improve the durability of
transmission and reception as a piezoelectric material of an ultrasonic probe, the dielectric
constant and the piezoelectricity An organic piezoelectric material and a method of
manufacturing the same. Another object of the present invention is to provide a low cost organic
piezoelectric material which does not use vapor deposition or CVD equipment by using the fine
particle dispersion technology, and a method of manufacturing the same.
[0007]
The above object of the present invention is achieved by the following constitution.
[0008]
1.
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A piezoelectric material characterized in that fine particles of a fluorine-based polymer material,
which is a fluorine-based piezoelectric material, are dispersed in fine particles in a polymer
material matrix of a non-fluorine-based piezoelectric material, coated or molded, and polarized.
[0009]
2. The piezoelectric material according to 1, wherein the average particle diameter of the fine
particles of the fluorine-based polymer material is 5 nm to 5 μm.
[0010]
3. The piezoelectric material according to 1 or 2, wherein the polymer material of the nonfluorine-based piezoelectric material is at least one selected from urea resin, polyester resin,
polyamide resin and polyolefin resin.
[0011]
4. The fluorine-based polymer material as the fluorine-based piezoelectric material is at least
one selected from vinylidene fluoride, ethylene trifluoride, hexafluoropropene and perfluoroalkyl
vinyl ether The piezoelectric material according to any one of the items.
[0012]
5. When fine particles of the fluorine-based polymer material of the fluorine-based
piezoelectric material are dispersed in the polymer material matrix of the non-fluorine-based
piezoelectric material, the particles of the fluorine-based polymer material are previously
dispersed in an average particle diameter of 5 nm to The piezoelectric material according to any
one of 1 to 4, which is dispersed and contained in 5 μm, or is sheared and dispersed by a shear
force of 300 sec <-1> to 5000 sec <-1>.
[0013]
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6. The proportion of the fluorine-based polymer material which is the fluorine-based
piezoelectric material in the polymer material matrix of the non-fluorine-based piezoelectric
material is 5% by mass or more and 90% by mass or less 1 The piezoelectric material as
described in any one of -5.
[0014]
7. The piezoelectric material according to any one of 1 to 6, wherein the polarization
treatment is direct current or alternating current voltage application treatment or corona
discharge treatment.
[0015]
An ultrasonic probe using the piezoelectric material according to any one of items 8 to 7.
[0016]
9.
In a polymer material matrix of a non-fluorine-based piezoelectric material, fine particles of a
fluorine-based polymer material, which is a fluorine-based piezoelectric material, are dispersed,
coated or molded, and polarization-processed. Method.
[0017]
10. 9. The method for producing a piezoelectric material according to 9, wherein the average
particle diameter of the fine particles of the fluorine-based polymer material is 5 nm to 5 μm.
[0018]
11. The polymer material of the non-fluorine-based piezoelectric material is at least one
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selected from urea resin, polyester resin, polyamide resin and polyolefin resin, wherein the
method for producing a piezoelectric material according to 9 or 10 is characterized.
[0019]
12. The fluorine-based polymer material as the fluorine-based piezoelectric material is at least
one selected from vinylidene fluoride, ethylene trifluoride, hexafluoropropene and perfluoroalkyl
vinyl ether The manufacturing method of the piezoelectric material of any one term.
[0020]
13. When fine particles of a fluorine-based polymer material, which is a fluorine-based
piezoelectric material, are dispersed in the polymer material matrix of the non-fluorine-based
piezoelectric material, fine particles of the fluorine-based polymer material are previously
dispersed to an average particle diameter of 5 nm. Manufacturing the piezoelectric material
according to any one of 9 to 12, characterized in that it is dispersed and contained in 5 to 5 μm,
or sheared and dispersed by a shear force of 300 sec <-1> to 5000 sec <-1>. Method.
[0021]
14. The proportion of the fluorine-based polymer material which is the fluorine-based
piezoelectric material in the polymer material matrix of the non-fluorine-based piezoelectric
material is 5% by mass to 90% by mass. The manufacturing method of the piezoelectric material
of any one of -13.
[0022]
15. The method for producing a piezoelectric material according to any one of 9 to 14,
wherein the polarization treatment is direct current or alternating current voltage application
treatment or corona discharge treatment.
[0023]
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A manufacturing method of an ultrasonic probe using a manufacturing method of a piezoelectric
material given in any 1 paragraph of 16.9-15.
[0024]
According to the present invention, the adhesion failure of the fluorine-based polymer material as
the organic piezoelectric material in the multilayer composite formation of the electrode, the
organic piezoelectric material, and the inorganic piezoelectric material used for the ultrasonic
probe of the ultrasonic diagnostic apparatus To provide an organic piezoelectric material
excellent in dielectric constant and piezoelectricity, and a method of manufacturing the same,
although it is possible to improve the durability of the ultrasonic probe as the piezoelectric
material and improve the durability of the transmission and reception as the piezoelectric
material of the ultrasonic probe. Can.
Further, by using the fine particle dispersion technology, it is possible to provide a low cost
organic piezoelectric material and a method of manufacturing the same without using vapor
deposition or CVD equipment.
[0025]
The best mode for carrying out the present invention will be described below, but the present
invention is not limited thereto.
[0026]
The piezoelectric material and the method of manufacturing the same according to the present
invention disperse fine particles of a fluorine-based polymer material of a fluorine-based
piezoelectric material in a polymer material matrix of a non-fluorine-based piezoelectric material,
and coat or shape it. It is one of the features that you did.
[0027]
Urea resin, polyamide resin, polyester resin etc. can be mentioned as a typical resin as a nonfluorine type polymer material of the non-fluorine type piezoelectric material concerning the
present invention.
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In particular, urea resins and polyamide resins having ̶NHCO̶ groups as polar groups are
preferred.
[0028]
The synthesis of the urea resin can be obtained by the addition reaction of a diisocyanate
compound and a diamine compound.
The following compounds can be mentioned as a preferable diamine compound used as a raw
material.
[0029]
As a diamine compound having a primary amino group, for example, bis- (3-aminopropyl) ether,
1,2-bis- (3-aminopropoxy) ethane, 1,3-bis- (3-aminopropoxy) -2 Aliphatic diamines such as 2dimethylpropane, bis- (3-aminopropyl) -diethylene glycol ether, bis- (3-aminopropyl) dipropylene glycol ether; bisaminopropyl polyethylene glycol ether, bisaminopropyl
polypropylene glycol ether , Bisaminopropyl polytetramethylene glycol ether,
diaminopolyethylene glycol, diaminopolypropylene glycol, diaminopolytetramethylene glycol,
polyamino polyethylene glycol, polyaminopolypropylene glycol , Polyalkylene polyether diamines
such polyamino polytetramethylene glycol; diaminodiphenyl ether; and the like. Moreover, as an
aliphatic diamine, ethylenediamine, a 1, 2- propylene diamine, a 1, 3- propylene diamine, a 1, 4butane diamine or hexamethylene diamine etc. are mentioned, for example. Examples of alicyclic
diamines include isophorone diamine, dicyclohexyl methane diamine, methyl cyclohexane
diamine, isopropylidene bis-4-cyclohexyl diamine, 1,4-cyclohexane diamine and the like.
Examples of heterocyclic diamines include piperazine, methyl piperazine, aminoethyl piperazine
and the like.
[0030]
As the isocyanate compound, for example, hexamethylene diisocyanate, 2,4-diisocyanate-1-1methylcyclohexane, diisocyanate cyclobutane, tetramethylene diisocyanate, o-, m- or p-xylylene
diisocyanate, hydrogenated xylylene diisocyanate, Aliphatic isocyanates such as
dicyclohexylmethane diisocyanate, dimethyldicyclohexylmethane diisocyanate, lysine
diisocyanate, cyclohexane diisocyanate, dodecane diisocyanate, tetramethylxylene diisocyanate
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or isophorone diisocyanate, tolylene-2,4-diisocyanate, tolylene-2,6-diisocyanate,
diphenylmethane-4 , 4'-diisocyanate, 3-methyl dif Nylmethane-4,4'-diisocyanate, m- or pphenylene diisocyanate, chlorophenylene-2,4-diisocyanate, naphthalene-1,5-diisocyanate,
diphenyl-4,4'-diisocyanate, 3,3'-dimethyldiphenyl There may be mentioned aromatic isocyanates
such as 1,3,5-triisopropylbenzene-2,4-diisocyanate carbodiimide-modified diphenyl meta
diisocyanate and isocyanate monomers such as phenyl ether diisocyanate.
[0031]
Examples of organic solvents for oligomer synthesis include ester solvents such as methyl
acetate, ethyl acetate, (iso) propyl acetate, (iso) butyl acetate, ethylene glycol diethyl ester; methyl
cellosolve, cellosolve, butyl cellosolve, isobutyl cellosolve, t -Butyl cellosolve, isopropyl cellosolve,
hexyl cellosolve, methoxybutanol, 3-methyl-3-methoxybutanol, methyl carbitol, carbitol, butyl
carbitol, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, methyl
glycol acetate, cellosolve acetate, Butyl glycol acetate, methoxypropyl acetate, methoxybutyl
acetate, carbitol acetate, butyl carbitol acetate, sorbite Glycol ether solvents such as cetate;
ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, methyl amyl
ketone and ethyl amyl ketone; methanol, ethanol, n (iso) -propanol, n (iso) -butanol, t-butanol
Alcohol solvents such as toluene; aromatic hydrocarbon solvents such as toluene, xylene and
ethylbenzene; paraffin hydrocarbons such as hexane, heptane, octane, nonane and decane;
cyclohexane, methylcyclohexane, dimethylcyclohexane, diethylcyclohexane,
trimethylcyclohexane And naphthene-based hydrocarbon solvents; and the like.
[0032]
The diisocyanate compound and the diamine compound may be polymerized as they are without
solvent, or may be dissolved in a polar solvent such as DMF, DMSO, acetone, MEK or the like for
polymerization.
[0033]
The polymerization can proceed in the temperature range from room temperature to the boiling
point of the above solvent.
[0034]
Typical polyamide resins are commercially available.
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For example, polyamide 6, polyamide 66, polyamide 610, polyamide 612, polyamide MXD 6,
polyamide 11, polyamide 12, polyamide 46, methoxylated polyamide (existing chemical
substance (7) -383) and the like.
The polyimide can mention the existing chemical substance number (7) -2211 (CAS No. 611-790) which NASA developed.
[0035]
Typical examples of the polyester resin include polyethylene terephthalate (PET) and
polynaphthalene phthalate (PEN).
Examples of the polyolefin resin include polyethylene and polypropylene.
[0036]
As the fluorine-based polymer material of the fluorine-based piezoelectric material according to
the present invention, polyvinylidene chloride, poly (ethylene trifluoride), polyhexafluoropropene,
polyperfluoroalkyl vinyl ether, polytetrafluoroethylene, or a combination of these is preferable.
Copolymers can be mentioned.
[0037]
The fine particles of the fluorine-based polymer material according to the present invention can
be produced by dispersing the polymer composition obtained by suspension polymerization,
emulsion polymerization, bulk polymerization and the like with a dispersing machine having a
shearing force.
A bead mill, a ball mill, a planetary mill, etc. can be micronized using media.
Other examples include sand grinder mills, screw mills, and propeller blades with sharp blades.
Then, in order to disperse in a size of about 5 nm to 300 nm, the non-fluorinated polymer
material according to the present invention and the fluorine-based polymer material according to
14-04-2019
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the present invention are added in a small piece to a screw mill. There is a method of kneading. It
is preferable to disperse | distribute with the high shear screw extrusion type disperser which
exists in Unexamined-Japanese-Patent No. 2005-313608. Although the rotation speed is usually
100 to 300 rpm, this device can achieve a rotation speed of 2000 to 5000 rpm, and a shearing
force of 300 sec <-1> to 3000 sec <-1> can be obtained. It is possible to break up to fine particles
of about 500 nm. It is possible to disperse to the nm size by circulating in the feedback type
diameter. It is preferable to mix in advance with the non-fluorinated polymer material according
to the present invention by dispersing it appropriately in such a manner that the average particle
size becomes about 5 nm to 5 μm by the above-mentioned disperser. When the shear force is
1000 sec <-1> or more, a shear force of 1000 or more can be obtained.
[0038]
In the piezoelectric material of the present invention and the method for producing the same, the
average particle diameter of the fine particles of the fluorine-based polymer material according
to the present invention is preferably 5 nm to 5 μm. When the thickness is 5 nm or more, the
piezoelectric effect is exhibited without lowering the tear strength of the polymer matrix, which
is preferable. Further, by setting the thickness to 5 μm or less, a smooth film surface is
maintained without being exposed from the inside of the polymer matrix film, and thus it is
preferable because the conductive effect of the electrode is exhibited.
[0039]
According to the piezoelectric material of the present invention and the method for producing
the same, the proportion of the fluorine-based polymer material of the fluorine-based
piezoelectric material of the present invention in the polymer material matrix of the non-fluorinebased piezoelectric material is 5% by mass It is preferable that it is 90 mass% or less. When the
content is 5% by mass or more, a piezoelectric effect is exhibited by the action of increasing the
dielectric constant, which is preferable. And by being 90 mass% or less, the effect of preventing a
dielectric breakdown and improving durability is exhibited, and it is preferable.
[0040]
The polarization treatment according to the present invention can perform corona discharge
treatment in addition to direct current, alternating current, and pulse voltage treatment of these.
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[0041]
The voltage of direct current or alternating current can be appropriately selected in the range of
1 V to 1 GV / m.
Corona discharge treatment can be performed at a discharge density of 1 W to 1 kW / m <2> /
sec.
[0042]
At the time of corona discharge treatment, since dielectric breakdown is likely to occur, it is
preferable to adhere the dielectric thin film and perform corona discharge treatment as
protection on the organic thin film. As the dielectric thin film, a thin film which is electrically
insulating and excellent in heat resistance and voltage resistance is used. For example, a sheet of
an olefin resin such as polyethylene, polypropylene or α-polyolefin, polyester, polystyrene,
polyfluorofluorine Sheets of synthetic resins such as vinylidene fluoride, polycarbonate, ethylene
tetrafluoride, polyphenylene sulfide, polyvinyl chloride, polyvinylidene chloride and the like,
copolymers of two or more kinds of them, blend molded products, nonpolar glass plates and the
like can be mentioned.
[0043]
When manufacturing the organic piezoelectric film, any substrate such as glass, resin or silicon
wafer is optional, but for low temperature thin film formation, polyester resin such as
polyethylene phthalate or polyethylene naphthalate, polycarbonate resin, silicon resin, alkylate
resin And a substrate such as cycloolefin resin can be appropriately selected. However, using an
inorganic piezoelectric material for the substrate and the substrate is convenient for forming a
piezoelectric element having an organic-inorganic multilayer structure. Such inorganic materials
may include quartz, lithium niobate (LiNbO3), potassium niobate tantalate [K (Ta, Nb) O3],
barium titanate (BaTiO3), lithium tantalate (LiTaO3) .
[0044]
With the organic piezoelectric film shown above, a high-performance piezoelectric film can be
obtained to realize a highly sensitive medical ultrasonic diagnostic apparatus.
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[0045]
In the following examples, the results of trial manufacture of an ultrasonic probe are shown.
[0046]
First, a fluorine-based resin is obtained to form fine particles, and furthermore, a piezoelectric
resin in which fluorine-based fine particles are dispersed in a non-fluorine-based resin in
nanosize by mixing high shear force with the non-fluorine-based resin. You can get
[0047]
EXAMPLES Hereinafter, the present invention will be specifically described by way of examples,
but the present invention is not limited thereto.
[0048]
Example 1 Synthesis of Fluorine-Based Polymer Material Synthesis of FP1 A polymer of P (VDFPFA) (composition molar ratio: VDF / perfluoroalkyl vinyl ether = 75 / .25) was synthesized.
[0049]
That is, VDF and PFA were dissolved in an acetone solution so as to have a concentration of 15%
by mass at a mass ratio of 2: 1, and initiator di-t-butylperoxide (DTBP) was used.
The concentration of the initiator was adjusted to be 1.2% by mass.
Polymerization was carried out at 80 ° C. for 3 hours to obtain FP1.
[0050]
<Synthesis of FP2> A polymer of P (VDF-PFA) (composition molar ratio: VDF / perfluoroalkyl
vinyl ether = 75/25) was synthesized.
[0051]
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That is, they were synthesized in the same manner as FP1 except that here di-ipropylperoxydicarbonate (IPP) was used as an initiator and DMDSO was used as a solvent.
[0052]
<Synthesis of FP3> A polymer of P (VDF-HFP) (composition molar ratio: VDF / HFP
(hexafluoropropene) = 75/25) was synthesized.
[0053]
That is, it was synthesized in the same manner as FP1 except that here HFP was used instead of
PFA, di-i-propylperoxydicarbonate (IPP) was used as an initiator and DMF was used as a solvent.
[0054]
<Synthesis of FP4> A polymer of P (VDF-TrF) (composition molar ratio: VDF / trifluoroethylene =
75/25) was synthesized.
[0055]
That is, VDF and TrF were dissolved in a DMF solution to a concentration of 15% by mass at a
mass ratio of 2: 1, and initiator di-t-butylperoxide (DTBP) was used.
The concentration of the initiator was adjusted to be 0.8% by mass of the solvent.
[0056]
<< Synthesis of Non-Fluorine-Based Polymer Material >> <Synthesis of NFP 1> An oligomer of
diphenylmethane diisocyanate was produced.
[0057]
That is, 4,4'-diphenylmethane isocyanate and 4,4'-diphenylmethanediamine are dissolved in
acetone at a concentration of 30% by mass and added to a thermostat at 20 ° C. for 11 hours,
respectively. I did.
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The solvent was removed by distillation to obtain NFP1.
[0058]
<Substrate: Preparation of PZT Inorganic Piezoelectric Element> In PZT, the components of lead,
zirconium and titanium are within the range of the formula Pb (Zr1-xTix) O3 (0.47 ≦ x ≦ 1), and
here A PZT of x = 0.2 was prepared.
Each oxide was weighed, pure water was added, and mixed in pure water in a ball mill containing
a medium made of zirconia for 8 hours, and sufficiently dried to obtain a mixed powder.
The obtained mixed powder was preformed, and calcined in air at 800 ° C. for 2 hours to
prepare a calcined product.
Next, pure water was added to the obtained calcined product, finely pulverized in a pure water in
a ball mill containing a medium made of zirconia, and dried to prepare a piezoelectric ceramic
raw material powder.
6% by mass of pure water as a binder is added to each piezoelectric ceramic raw material powder
having different particle diameters, and press-formed to form a 530-μm thick plate-shaped
temporary compact, and the plate-shaped temporary compact is vacuum-packed, 235 MPa It
shape | molded by the press by the pressure of.
Next, the above-mentioned compact was fired to obtain a final sintered body having a thickness
of 41 μm.
The firing temperatures were 780 ° C., respectively.
The polarization process was performed by applying an electric field of 1.5 × Ec (MV / m) or
more for 1 minute.
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[0059]
Using the high shear kneader described in JP-A-2005-313608 for the non-fluorinated polymer
materials listed in Table 1 for the polymer materials synthesized above using the fluorine-based
polymer materials listed in Table 1 Knead and shear to a size listed in Table 1, then apply 20 μm
thick on the PZT inorganic piezoelectric element and perform corona discharge treatment as
shown in Table 1 as polarization processing to obtain a high PZT inorganic piezoelectric element
Ultrasonic probe samples 101 to 113 having organic polymer piezoelectric element layer films
(piezoelectric materials) 101 to 113 (polymer alloy piezoelectric layer films) formed thereon
were produced. The polarization temperature was 180.degree.
[0060]
<< Performance test >> With regard to the above ultrasonic probe sample, electrodes are pulled
out from both ends of the element and a voltage is applied to this terminal to transmit a
fundamental frequency f1 of 7.5 MHz, and a reception relative sensitivity of 15 MHz as a
reception harmonic f2 ( The reception relative sensitivity is a value obtained by multiplying the
ratio of the output voltage to the input voltage by a constant. Asked for). The reception relative
sensitivity used the sound intensity measurement system Model 805 (1 to 50 MHz)
measurement system of Sonora Medical Systems, Inc. (Sonora Medical System, Inc: 2021 Miller
Drive Longmont, Colorado (0501 USA)).
[0061]
The results are shown in Table 1.
[0062]
[0063]
From Table 1, it can be seen that in the case of the present invention in the polymer alloy state,
the reception relative sensitivity is good and good piezoelectric performance is obtained.
[0064]
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A polymeric piezoelectric resin in which fine particles of a fluorine-based polymer material of a
fluorine-based piezoelectric material are dispersed in a polymer material matrix of a nonfluorine-based piezoelectric material according to the present invention exhibits good reception
relative sensitivity and piezoelectricity. I understand that.
In particular, a system dispersed in nanoparticle size can provide high reception relative
sensitivity and piezoelectric performance.
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