Acoustic wave probe, acoustic wave measurement device, and ultrasonic diagnosis device

Abstract

Provided are: an acoustic wave probe comprising a substrate, an intermediate layer arranged on the substrate, and an acoustic lens layer arranged on the intermediate layer, in which the intermediate layer is a layer containing a siloxane compound, the siloxane compound has a constituent unit derived from a hydrolysable silicate compound, the acoustic lens layer is a layer produced by curing a room-temperature-curable silicone, and the room-temperature-curable silicone contains a constituent unit having a phenyl group; an acoustic wave measurement device; and an ultrasonic diagnosis device.

Description

Acoustic wave probe, acoustic wave measuring device, and ultrasonic diagnostic device

[0001] The present invention relates to an acoustic wave probe, an acoustic wave measuring device, and an ultrasonic diagnostic device.

[0002] An acoustic wave measurement device uses an acoustic wave probe that irradiates an object or region under test (hereinafter simply referred to as the object) with acoustic waves, receives the reflected waves (echoes), and outputs a signal. The electrical signals converted from the reflected waves received by the acoustic wave probe are displayed as an image. This allows the interior of the object to be visualized and observed.

[0003] The acoustic wave may be an ultrasound wave, a photoacoustic wave, or any other wave having an appropriate frequency depending on the object to be examined or the measurement conditions. For example, an ultrasound diagnostic device transmits ultrasound toward the inside of the object to be examined, receives the ultrasound reflected by tissue inside the object, and displays it as an image. A photoacoustic wave measurement device receives acoustic waves emitted from the inside of the object to be examined due to the photoacoustic effect, and displays it as an image. The photoacoustic effect is a phenomenon in which, when an electromagnetic wave pulse such as visible light, near-infrared light, or microwave is irradiated onto the object to be examined, the object absorbs the electromagnetic wave, generates heat, and thermally expands, generating an acoustic wave (typically an ultrasound wave).

[0004] Since an acoustic wave measuring device transmits and receives acoustic waves to and from a living body, which is the subject of examination, it is required, for example, to match the acoustic impedance with the living body (typically a human body) and also to suppress the amount of acoustic wave attenuation. For example, a probe for an ultrasound diagnostic device (also called an ultrasound probe), which is a type of acoustic wave probe, includes a piezoelectric element that transmits and receives ultrasound waves and an acoustic lens that is the part that comes into contact with the living body. Ultrasound emitted from the piezoelectric element passes through the acoustic lens and is incident on the living body. If there is a large difference between the acoustic impedance (density x speed of sound) of the acoustic lens and the acoustic impedance of the living body, the ultrasound will be reflected by the surface of the living body and will not be efficiently incident on the living body. As a result, it becomes difficult to obtain good resolution. Furthermore, in order to transmit and receive ultrasound waves with high sensitivity, it is desirable to suppress the amount of ultrasound attenuation of the acoustic lens. For this reason, one material for the acoustic lens is a material that matches the acoustic impedance of the living body (1.4 to 1.7 × 10 for the human body).６ kg / m ２ / sec) and has a small ultrasonic attenuation. In order to reduce the difference in acoustic impedance between the piezoelectric element and the acoustic lens and to efficiently transmit and receive ultrasonic waves, an acoustic matching layer is usually provided between the piezoelectric element and the acoustic lens.

[0005] Furthermore, when using an acoustic wave measurement device, acoustic waves are transmitted and received by rubbing the acoustic wave probe against a living body. Therefore, high mechanical strength is required for the acoustic lens, which is the part that is rubbed against the living body and sometimes pressed when used. Because silicone resins are generally soft and have poor mechanical strength, attempts have been made to improve mechanical strength by mixing inorganic fillers into the silicone resin or by introducing a crosslinked structure. For example, Patent Document 1 describes a composition for an acoustic wave probe containing a polysiloxane mixture including a polysiloxane having a vinyl group, a polysiloxane having two or more Si—H groups in the molecular chain, and surface-treated silica particles with an average primary particle diameter of more than 16 nm and less than 100 nm. Furthermore, Patent Document 2 describes an elevation-angle focused ultrasonic probe equipped with an array of micromachined ultrasonic transducer (MUT) cells, which includes an adhesion layer containing an adhesion agent consisting of silicate, an organometallic compound, or a reactive organosilane between the array and a lens made of room-temperature-curable silicone rubber.

[0006] International Publication No. 2017 / 130890 Japanese Patent Application Laid-Open No. 2005-103294

[0007] Acoustic wave probes used for examining or treating the human body are typically used in direct contact with the human body. For example, intracavity probes used for intracavity procedures such as transvaginal, transrectal, or transesophageal procedures are likely to come into contact with mucous membranes and may come into contact with sterile tissue and blood. Surface probes used for abdominal or pelvic scans may also come into contact with sterile tissue, wounded skin, mucous membranes, or intact skin, depending on the procedure. Therefore, acoustic wave probes require a high level of cleanliness beyond disinfection to prevent bacterial infection. Sterilization using EOG (ethylene oxide gas), which allows for low-temperature processing, is widely used as such sterilization treatment, and hydrogen peroxide plasma treatment is also becoming increasingly desirable.

[0008] As a result of the inventor's research, it has been found that in an acoustic wave probe in which an acoustic lens is disposed directly on an acoustic matching layer, as described in Patent Document 1, adhesion between the acoustic matching layer and the acoustic lens is poor, and even in an ultrasonic probe in which an adhesion layer containing an adhesion agent made of silicate, organometallic compound, or reactive organosilane is interposed between the acoustic matching layer and the acoustic lens, as described in Patent Document 2, adhesion between the acoustic matching layer and the acoustic lens decreases when repeatedly subjected to hydrogen peroxide plasma sterilization treatment. This decrease in adhesion causes a decrease in the performance of the acoustic wave probe. Therefore, acoustic wave probes are required to have a high level of sterilization durability.

[0009] An object of the present invention is to provide an acoustic wave probe that has excellent adhesion and durability against sterilization, and an acoustic wave measuring device or an ultrasonic diagnostic device that includes the acoustic wave probe.

[0010]

[0009] In view of the above problems, the present inventors conducted extensive research and found that the above problems can be solved by providing an intermediate layer between a substrate such as an acoustic matching layer and an acoustic lens layer, making this acoustic lens layer a layer formed by curing a room-temperature-curable silicone containing a structural unit having a phenyl group, and by configuring the intermediate layer as a layer containing a siloxane compound, where this siloxane compound contains a structural component derived from a hydrolyzed silicate compound. The present invention was completed after further research based on these findings.

[0011] The above problems have been solved by the following means. <1> An acoustic wave probe having a substrate, an intermediate layer on the substrate, and an acoustic lens layer on the intermediate layer, wherein the intermediate layer is a layer containing a siloxane compound, the siloxane compound having a component derived from a hydrolyzed silicate compound, and the acoustic lens layer is a layer formed by curing a room-temperature curable silicone, the room-temperature curable silicone including a structural unit having a phenyl group. <2> The acoustic wave probe according to <1>, wherein the substrate contains at least one of iron, a non-ferrous metal, an inorganic material other than a metal, and an organic material. <3> The acoustic wave probe according to <2>, wherein the non-ferrous metal contains at least one of aluminum, titanium, magnesium, nickel, copper, lead, zinc, tin, chromium, tungsten, or cobalt, or an alloy of at least two of these metals. <4> The acoustic wave probe according to <2> or <3>, wherein the inorganic material other than a metal contains at least one of glass, ceramics, and graphite. <5> The acoustic wave probe according to any one of <2> to <4>, wherein the organic material comprises at least one of a thermoplastic resin and a thermosetting resin. <6> The acoustic wave probe according to <5>, wherein the thermoplastic resin comprises at least one of an acrylic resin, a polycarbonate resin, a styrene-based resin, and a polyphenylene sulfide resin. <7> The acoustic wave probe according to <5> or <6>, wherein the thermoplastic resin is a crosslinked thermoplastic resin. <8> The acoustic wave probe according to any one of <1> to <7>, wherein the substrate has been subjected to a hydrophilization treatment on the surface of the intermediate layer side. <9> The acoustic wave probe according to <8>, wherein the substrate has been subjected to at least one of an ultraviolet treatment, an ozone treatment, a plasma treatment, and a corona treatment on the surface of the intermediate layer side. <10> The acoustic wave probe according to any one of <1> to <9>, wherein the intermediate layer comprises a component derived from at least one of a silane coupling agent, a titanium alkoxide compound, an aluminum alkoxide compound, and a zirconium alkoxide compound. <11> The acoustic wave probe according to any one of <1> to <10>, wherein the room-temperature-curable silicone is a silicone composition containing vinyl silicone and hydrosilicone.<12> The acoustic wave probe according to <11>, wherein the silicone composition contains surface-treated oxide particles. <13> The acoustic wave probe according to <12>, wherein the silicone composition contains surface-treated spherical silica particles. <14> The acoustic wave probe according to any one of <1> to <13>, wherein the acoustic wave probe is an ultrasound probe. <15> An acoustic wave measuring device comprising the acoustic wave probe according to any one of <1> to <13>. <16> An ultrasound diagnostic device comprising the acoustic wave probe according to <14>.

[0012] In the present invention, a "metal alkoxide compound (e.g., an aluminum alkoxide compound, a zirconium alkoxide compound, or a titanium alkoxide compound described below)" refers to a compound having a structure in which at least one alkoxy group is bonded to a metal atom. This alkoxy group may have a substituent. This substituent may be monovalent or divalent (e.g., an alkylidene group). Furthermore, two alkoxy groups bonded to one metal atom may be bonded to each other to form a ring. In the present invention, when there are multiple substituents, linking groups, etc. (hereinafter referred to as "substituents, etc.") designated by a specific symbol, or when multiple substituents, etc. are specified simultaneously or alternatively, this means that the respective substituents, etc. may be the same or different from each other. Furthermore, even if not otherwise specified, when multiple substituents, etc. are adjacent, they may be bonded to each other or fused to form a ring. In the present invention, with respect to substituents (the same applies to linking groups) that are not specified as substituted or unsubstituted, this means that the group may have any substituent within the range in which the desired effect is exhibited. This also applies to compounds for which substituted or unsubstituted is not specified. In the present invention, when the number of carbon atoms in a certain group is specified, this carbon number refers to the total number of carbon atoms in the group. In other words, if this group further has a substituent, this refers to the total number of carbon atoms including the substituent. In the present invention, "Si-H group" and "Si-OH group" refer to groups having three additional bonds on the silicon atom, the description of which is omitted. Furthermore, [-Si-O] refers to a group having two additional bonds on the silicon atom, the description of which is omitted. In the present invention, the term "reactive functional group" is used in a broader sense than usual. In other words, it includes groups that react with other groups to form covalent bonds, etc., as well as groups that interact with other groups (ionic interactions, hydrogen bonds, etc.). In addition, in the present invention, unsubstituted alkoxy groups are not considered to have a structure having a reactive functional group. In addition, in the present invention, a numerical range expressed using "to" refers to a range that includes the numerical values ​​before and after it as the lower and upper limits.

[0013] The acoustic wave probe of the present invention has excellent initial adhesion and excellent durability against sterilization. The acoustic wave measuring device and ultrasonic diagnostic device of the present invention also have the acoustic wave probe with the above-mentioned excellent performance.

[0014] FIG. 1 is a perspective view of an example of a convex ultrasonic probe, which is one aspect of an acoustic wave probe.

[0015] <<Acoustic Wave Probe (Acoustic Wave Probe)>> The acoustic wave probe of the present invention is an acoustic wave probe having a substrate, an intermediate layer on the substrate, and an acoustic lens layer on the intermediate layer, wherein the intermediate layer is a layer containing a siloxane compound, and the siloxane compound has a constituent component derived from a hydrolyzed silicate compound, and the acoustic lens layer is a layer formed by curing a room-temperature curable silicone, and the room-temperature curable silicone contains a constituent unit having a phenyl group.

[0016] The acoustic wave probe of the present invention has excellent initial adhesion and also excellent sterilization durability. Although the reason for this is not clear, one possible reason is that the siloxane compound contained in the intermediate layer has a component derived from a hydrolyzed silicate compound, and the acoustic lens layer is a layer formed by curing a room-temperature-curable silicone, so that a chemical bond is formed at the interface between the intermediate layer and the acoustic lens layer due to a reaction between the hydrophilic group (silanol group [Si—OH]) of the hydrolyzed silicate compound and the hydrosilyl group [Si—H] of the room-temperature-curable silicone. Furthermore, because the acoustic lens layer in the present invention is a layer formed by curing a room-temperature-curable silicone containing a structural unit with a phenyl group, the large molecular size of the phenyl groups present in the acoustic lens layer makes it possible to suppress the permeation of hydrogen peroxide gas and decomposition and activated products of hydrogen peroxide gas generated by plasma irradiation (hereinafter abbreviated as "hydrogen peroxide gas, etc."), even when subjected to hydrogen peroxide plasma sterilization treatment, which has strong chemical properties, and this is thought to be one reason why the amount of hydrogen peroxide gas, etc. that reaches the interface between the acoustic lens layer and the intermediate layer, and further the interface between the intermediate layer and a substrate such as an acoustic matching layer, can be reduced. Hydrogen peroxide gas, etc. can sever organic components, particularly chemical bonds that contribute to the adhesion of materials near the interface, and it is thought that the configuration of the present invention can exhibit excellent resistance to hydrogen peroxide plasma sterilization.

[0017] <Substrate> The substrate in the acoustic wave probe of the present invention is not particularly limited, and can be a wide variety of substrates that are used for components around the acoustic lens layer in acoustic wave probes, such as an acoustic matching layer. That is, the acoustic wave probe of the present invention has a configuration in which components located around the acoustic lens layer in a typical acoustic wave probe are bonded to the acoustic lens layer via the intermediate layer. Of the components located around the acoustic lens layer, the component bonded to the acoustic lens layer via the intermediate layer serves as the substrate in the acoustic wave probe of the present invention. An acoustic matching layer is suitable as the substrate, and it is preferable that the acoustic matching layer be bonded to the acoustic lens layer via the intermediate layer.

[0018] The substrate preferably contains at least one of iron, non-ferrous metal, inorganic material other than metal, and organic material.

[0019] In the present invention, metallic materials containing iron are classified as iron, and metallic materials not containing iron are classified as non-ferrous metals. That is, the term "iron" includes not only pure iron but also alloys of iron with non-ferrous metal elements and / or non-metal elements. Examples of such alloys containing iron include stainless steel. Examples of non-ferrous metals include aluminum, titanium, magnesium, nickel, copper, lead, zinc, tin, chromium, tungsten, cobalt, vanadium, or gold, or alloys of at least two of these metals. Non-ferrous metals are preferred as metallic materials because they have superior resistance to hydrogen peroxide plasma sterilization. From the viewpoint of low catalytic activity against hydrogen peroxide, the non-ferrous metal preferably contains at least one of aluminum, titanium, magnesium, nickel, copper, lead, zinc, tin, chromium, tungsten, or cobalt, or an alloy of at least two of these metals; more preferably, it contains at least one of aluminum, titanium, nickel, copper, chromium, tungsten, or cobalt, or an alloy of at least two of these metals; even more preferably, it contains at least one of copper, aluminum, or tungsten, or an alloy of at least two of these metals; and particularly preferably, it contains at least one of copper, aluminum, or an alloy of these metals.

[0020] Examples of the inorganic material other than metal include glass, ceramics, and graphite, and it is preferable to include at least one of glass, ceramics, and graphite. Examples of the glass include sodium soda glass, Pyrex (registered trademark) glass, quartz glass, and alkali-free glass. The ceramic refers to an inorganic compound such as an oxide, carbide, nitride, or boride of at least one element selected from metal elements and non-metal elements, and examples thereof include alumina, zirconia, silicon carbide, and silicon nitride. Examples of the graphite include natural graphite and artificial graphite.

[0021] The organic material is usually a solid material, and preferably contains at least one of a thermoplastic resin and a thermosetting resin. Examples of the thermoplastic resin include polyolefin resins such as polyethylene resin, polypropylene resin, and polymethylpentene resin, styrene-based resins such as polystyrene resin, ABS resin (acrylonitrile-butadiene-styrene copolymer resin), and acrylonitrile-styrene copolymer resin, acrylic resin, thermoplastic polyimide resin, thermoplastic polyamide resin, polyetherimide resin, polyphenylene ether resin, polycarbonate resin, polyester resins such as polyethylene terephthalate resin, polybutylene terephthalate resin, and polyethylene naphthalate resin, polyphenylene sulfide resin, polyether ether ketone resin, polyether sulfone resin, and thermoplastic polycycloolefin resins such as thermoplastic polynorbornene resin. The thermoplastic resin preferably contains at least one of acrylic resin, polycarbonate resin, styrene-based resin, and polyphenylene sulfide resin from the viewpoint of excellent secondary processability such as cutting and machining for making an ultrasonic probe, and more preferably contains a crosslinked thermoplastic resin, and even more preferably contains a crosslinked polystyrene-based resin, from the viewpoint of excellent resistance to hydrogen peroxide plasma sterilization and heat cycle resistance. The crosslinked thermoplastic resin may be any resin in which a crosslinked structure is introduced, and the crosslinked structure can be introduced by a conventional method without any particular limitation.

[0022] Examples of the thermosetting resin include epoxy resin, phenol resin, melamine resin, urethane resin, thermosetting polyimide resin, thermosetting polyamide resin, polyamide-imide resin, unsaturated polyester resin, and thermosetting polycycloolefin resin such as thermosetting polynorbornene resin. The unsaturated polyester resin refers to a resin obtained by dissolving an unsaturated polyester produced by polycondensation of an unsaturated dicarboxylic acid such as fumaric acid or maleic anhydride with a dihydric alcohol such as ethylene glycol in a polymerizable monomer such as styrene or methyl methacrylate. From the viewpoint of further enhancing hydrogen peroxide plasma sterilization resistance, the thermosetting resin preferably includes at least one of phenol resin, unsaturated polyester resin, thermosetting polyimide resin, thermosetting polyamide resin, polyamide-imide resin, and thermosetting polycycloolefin resin, and more preferably includes at least one of unsaturated polyester resin, thermosetting polyimide resin, and thermosetting polyamide-imide resin.

[0023] From the viewpoint of further enhancing resistance to hydrogen peroxide plasma sterilization and heat cycle resistance, the organic material preferably contains at least one of a thermosetting resin and a crosslinked thermoplastic resin, and more preferably contains at least one of a thermosetting polyimide resin, an unsaturated polyester resin, and a crosslinked polystyrene resin.

[0024] From the viewpoint of further enhancing hydrogen peroxide plasma sterilization resistance, the substrate preferably contains at least one of a non-ferrous metal, an inorganic material other than a metal, and an organic material; from the viewpoint of further enhancing heat cycle resistance in addition to hydrogen peroxide plasma sterilization resistance, the substrate more preferably contains at least one of an inorganic material other than a metal and an organic material; and from the viewpoint of further enhancing hydrogen peroxide plasma sterilization resistance and heat cycle resistance, the substrate still more preferably contains at least one of a thermosetting resin and a crosslinked thermoplastic resin.

[0025] The total content of iron, non-ferrous metals, inorganic materials other than metals, and organic materials contained in the substrate is not particularly limited, and can be, for example, 80% by mass or more, preferably 90% by mass or more, or even 100% by mass. When the iron, non-ferrous metals, inorganic materials other than metals, and organic materials contained in the substrate are limited to specific materials, the total content of the limited materials can be, for example, 80% by mass or more, preferably 90% by mass or more, or even 100% by mass. Therefore, when the substrate contains iron and organic materials, but does not contain non-ferrous metals or inorganic materials other than metals, the total content of iron and organic materials in the substrate can be the preferred content.

[0026] From the viewpoint of improving adhesion between the substrate and the intermediate layer, it is preferable that the substrate be subjected to a hydrophilization treatment on the surface facing the intermediate layer. The hydrophilized substrate surface has many reaction sites (hydrophilic groups) with the siloxane compound containing a component derived from the hydrolyzed silicate compound contained in the intermediate layer, thereby further improving peel strength and maintaining an excellent level of peel strength even after heat cycles and hydrogen peroxide plasma sterilization. The hydrophilization treatment is not particularly limited as long as it can provide (introduce) reaction sites with the siloxane compound containing a component derived from the hydrolyzed silicate compound contained in the intermediate layer to the substrate surface. Examples of the hydrophilization treatment include at least one treatment selected from ultraviolet (UV) treatment, ozone treatment, plasma treatment, and corona treatment. When two or more of these treatments are applied, the two or more treatments may be performed simultaneously or separately. The UV treatment, ozone treatment, plasma treatment, and corona treatment can be performed by conventional methods as long as they do not impair the effects of the present invention. From the viewpoint of further enhancing heat cycle resistance and hydrogen peroxide plasma sterilization resistance, the hydrophilization treatment is preferably at least one of UV treatment, plasma treatment, and corona treatment, and more preferably at least one of UV treatment and plasma treatment.

[0027] <Intermediate Layer> The intermediate layer in the acoustic wave probe of the present invention is a layer containing a siloxane compound, and this siloxane compound has a constituent component derived from a hydrolyzed silicate compound. The siloxane compound is a compound having a repeating structure of siloxane bonds ([—Si—O]), and is an oligomer or polymer obtained by polycondensation of silanol groups (Si—OH groups) contained in the hydrolyzed silicate compound.

[0028] The hydrolyzed silicate compound is a compound obtained by hydrolyzing a hydrolyzable group in a silicate compound and converting the hydrolyzable group into a silanol group. The silicate compound refers to a compound having a structure in which four O atoms are coordinated around one Si atom, and a plurality of Si atoms with four O atoms may be present in the compound. A compound having one Si atom with four O atoms coordinated thereto is called a silicate monomer (also called a silane compound), and a compound having two or more Si atoms with four O atoms coordinated thereto is called a silicate oligomer. In the present invention, the hydrolyzed silicate compound is preferably a hydrolyzed silicate oligomer.

[0029] The hydrolysis rate of the hydrolyzed silicate compound is not particularly limited as long as the effects of the present invention can be obtained, and for example, it may be 50% or more, preferably 60% or more, more preferably 70% or more, and even more preferably 80% or more. When a silicate compound having a hydrolyzable group is hydrolyzed in the presence of an acid or a base as described below, a hydrolyzed silicate compound having a hydrolysis rate corresponding to the amount of water used can usually be obtained. The hydrolysis rate of the commercially available hydrolyzed silicate compound or the hydrolyzed silicate compound used in the examples described below is 80% or more. The hydrolysis rate of the hydrolyzed silicate compound is determined by the number X of hydrolyzable groups contained in the hydrolyzed silicate compound. Ｈ and the number of hydroxy groups in the silanol group, X ＯＨ The value is calculated using the following formula: ３ The number of hydroxy groups in ＯＨThe calculation is 3. Hydrolysis rate in hydrolyzed silicate compound = 100% x X ＯＨ / (X Ｈ +X ＯＨ )

[0030] The hydrolyzed silicate compound may be a commercially available product, and for example, silicate hydrolyzed liquids manufactured by Nippon Colcoat Co., Ltd., such as Colcoat PX, Colcoat N-103X, HAS-1, HAS-6, and HAS-10 (all trade names), may be used.

[0031] Furthermore, compounds obtained by hydrolyzing silicate compounds having hydrolyzable groups can also be used as hydrolyzed silicate compounds. The hydrolysis reaction can be carried out by reacting a silicate compound having hydrolyzable groups in the presence of an acid or base as a catalyst. In contrast, the hydrolysis reaction hardly proceeds under neutral conditions in the absence of an acid or base. The acid or base used as the catalyst can be any acid or base commonly used in the hydrolysis reaction of silicate compounds, without any particular limitations. In particular, when a base is used as a catalyst, the use of an acid catalyst is preferred, and hydrochloric acid is more preferred, from the viewpoint of the ease with which gelation proceeds. The amount of water used in the hydrolysis reaction can be adjusted appropriately depending on the desired hydrolysis rate. As the solvent used in the hydrolysis reaction, a solvent in which the silicate compound having hydrolyzable groups and water are soluble can be used, and it is preferable to use one or more alcoholic solvents such as methanol, ethanol, isopropanol, and ethyl cellosolve. The reaction time for the hydrolysis reaction can be adjusted appropriately, for example, to 1 to 24 hours.

[0032] Examples of the hydrolyzable group include an alkoxy group (an alkyloxy group), an alkenyloxy group, an acyloxy group, an aminooxy group, an oxime group, and an amide group, with an alkoxy group being preferred.

[0033] The alkyl group in the alkoxy group may be linear, branched, or cyclic. The number of carbon atoms in this alkyl group is preferably 1 to 30, more preferably 1 to 20, even more preferably 1 to 10, and particularly preferably 1 or 2. Specific examples of the alkyl group include methyl, ethyl, isopropyl, butyl, and cyclopentyl. When the acyloxy group, aminoxy group, oxime group, and amide group are substituted with an alkyl group, the same descriptions as for the alkyl group in the alkoxy group can be applied to the alkyl group in the acyloxy group, aminoxy group, oxime group, and amide group.

[0034] The alkenyl group in the alkenyloxy group may be linear, branched, or cyclic, and preferably has 2 to 30 carbon atoms, more preferably 2 to 20 carbon atoms, and even more preferably 2 to 10 carbon atoms.

[0035] Among silicate compounds having hydrolyzable groups, silicate monomers include, for example, tetraalkoxysilane compounds. The tetraalkoxysilane compounds are not particularly limited, and examples thereof include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetraisopropoxysilane, and tetrabutoxysilane. Hydrolyzed silicate compounds can also be obtained by hydrolyzing a mixture of the tetraalkoxysilane compounds with trialkoxysilane compounds and / or dialkoxysilane compounds. The trialkoxysilane compounds and dialkoxysilane compounds have a structure in which three or two O atoms are coordinated around one Si atom, and are not classified as silicate compounds. The hydrolysis reaction conditions for the mixture can be the same as those for the hydrolysis reaction of silicate compounds having hydrolyzable groups described above. The trialkoxysilane compounds are not particularly limited, and examples thereof include methyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, and phenyltriethoxysilane. The dialkoxysilane compound is not particularly limited, and examples thereof include dimethyldimethoxysilane and dimethyldiethoxysilane.

[0036] Among silicate compounds having hydrolyzable groups, silicate oligomers can be obtained by the hydrolysis and condensation reaction of silicate monomers. Among silicate compounds having hydrolyzable groups, examples of silicate oligomers include the hydrolysis and condensation products of the above-mentioned tetraalkoxysilane compounds and the hydrolysis and condensation products of mixtures of the above-mentioned tetraalkoxysilane compounds with trialkoxysilane compounds and / or dialkoxysilane compounds. The number of Si atoms with four O atoms coordinated thereto in the silicate oligomer is preferably 2 to 200, more preferably 2 to 120. Among these, the hydrolysis and condensation products of tetraalkoxysilanes are preferred, the hydrolysis and condensation products of tetramethoxysilane and / or tetraethoxysilane are more preferred, and the hydrolysis and condensation products of tetramethoxysilane or tetraethoxysilane are even more preferred.

[0037] The silicate compound having a hydrolyzable group may be a commercially available product. For example, examples of silicate monomers that can be used include Ethyl Silicate 28, N-Propyl Silicate, and N-Butyl Silicate (all trade names) manufactured by Nippon Colcoat Co., Ltd.; and examples of silicate oligomers that can be used include Ethyl Silicate 40, Ethyl Silicate 48, Methyl Silicate 51, Methyl Silicate 53A, and EMS-485 (all trade names) manufactured by Nippon Colcoat Co., Ltd.; and MKC Silicate MS51, MS56, MS57, and MS56S (all trade names) manufactured by Mitsubishi Chemical Corporation.

[0038] The hydrolyzed silicate compound preferably has no organic groups other than methyl and ethyl.

[0039] The weight average molecular weight of the hydrolyzed silicate compound is not particularly limited, and is, for example, preferably 100 to 10,000, more preferably 150 to 4,000, and particularly preferably 200 to 2,500.

[0040] The weight-average molecular weight or number-average molecular weight of the compounds described herein is determined as follows. The weight-average molecular weight or number-average molecular weight can be measured as a polystyrene-equivalent molecular weight by gel permeation chromatography (GPC). Specifically, a GPC apparatus HLC-8220 (trade name, manufactured by Tosoh Corporation) is used, tetrahydrofuran is used as an eluent, and G3000HXL + G2000HXL columns (both trade names, manufactured by Tosoh Corporation) are used, and the molecular weight can be detected by RI (differential refractive index) at 23°C and a flow rate of 1 mL / min.

[0041] The acoustic wave probe of the present invention includes a form in which an intermediate layer containing a siloxane compound has reacted with at least one of the substrate and the acoustic lens layer. For example, the intermediate layer can be formed by reacting a hydroxy group of the siloxane compound with a group on the surface of the acoustic lens layer or the substrate.

[0042] The content of the siloxane compound in the intermediate layer is preferably 50% by mass or more, more preferably 70% by mass or more, even more preferably 80% by mass or more, and particularly preferably 90% by mass or more. There is no particular upper limit, and it is, for example, 100% by mass or less, preferably 99% by mass or less, and more preferably 98% by mass or less. That is, the content of the siloxane compound in the intermediate layer is preferably 50 to 100% by mass, more preferably 70 to 99% by mass, and even more preferably 80 to 98% by mass. The content of the hydrolyzed silicate compound in the liquid (which may contain a solvent) used to form the intermediate layer is, for example, preferably 1% by mass or more, more preferably 2% by mass or more, even more preferably 3% by mass or more, and particularly preferably 4% by mass or more. There is no particular upper limit, and it is, for example, 100% by mass or less, preferably 70% by mass or less, more preferably 50% by mass or less, and even more preferably 25% by mass or less. That is, the content of the hydrolyzed silicate compound in the liquid (including the solvent) used to form the intermediate layer is preferably 1 to 100 mass%, more preferably 2 to 70 mass%, even more preferably 3 to 50 mass%, and particularly preferably 4 to 25 mass%.

[0043] In the present invention, from the viewpoint of obtaining better peel strength, it is preferable that the intermediate layer further contains a component derived from at least one of a silane coupling agent, a titanium alkoxide compound, an aluminum alkoxide compound, and a zirconium alkoxide compound, and from the viewpoint of obtaining better heat cycle resistance and hydrogen peroxide plasma sterilization resistance, it is more preferable that the intermediate layer contains a component derived from an aluminum alkoxide compound.

[0044] (Silane Coupling Agent) As the silane coupling agent used in the present invention, a wide range of ordinary silane coupling agents applicable to the primer layer of the constituent members of the acoustic wave probe can be adopted. The silane coupling agent preferably does not have a siloxane bond, and preferably has a group other than methyl, ethyl, methoxy, and ethoxy (for example, an amino group, a vinyl group, a propyl group, an acid anhydride group, an epoxy group, or a mercapto group).

[0045] (Titanium Alkoxide Compound) As the titanium alkoxide compound (preferably a titanium coupling agent) used in the present invention, a wide range of ordinary titanium alkoxide compounds that can be used as a primer layer for components of an acoustic wave probe can be used.

[0046] The titanium alkoxide compound preferably contains at least one compound represented by the following general formula (a) or (b), and more preferably contains at least one compound represented by the following general formula (a): The total content of the compounds represented by the following general formula (a) or (b) in the titanium alkoxide compound is not particularly limited and can be, for example, 60% by mass or more, preferably 80% by mass or more, more preferably 90% by mass or more, even more preferably 95% by mass or more, or even 100% by mass.

[0047] General formula (a): R １ａ ｍ１ -Ti-(OR ２ａ ) ４－ｍ１ General formula (b): O-[Ti-(OR ２ａ ) ３ ] ２

[0048] R １ａ represents a hydrogen atom, an alkyl group, a cycloalkyl group, an acyl group, an aryl group, or an unsaturated aliphatic group. １ａ Examples of the alkyl group, cycloalkyl group, acyl group, aryl group and unsaturated aliphatic group that can be taken as R １ｂ Examples of the alkyl group, cycloalkyl group, acyl group, aryl group and unsaturated aliphatic group that can be taken as the alkyl group include alkyl, cycloalkyl, acyl, aryl and unsaturated aliphatic groups.

[0049] R ２ａ is a hydrogen atom, an alkyl group, a cycloalkyl group, an acyl group, an alkenyl group, an aryl group, a phosphonate group, or —SO ２ R Ｓ１ Indicates. Ｓ１ represents a substituent. ２ａ Examples of the alkyl group, cycloalkyl group, acyl group, alkenyl group, aryl group and phosphonate group that can be taken as R ２ｂ The alkyl group, cycloalkyl group, acyl group, alkenyl group, aryl group and phosphonate group that can be taken as R Ｓ１ Examples of the substituents that can be adopted as the substituent include R Ｓ２ The substituents that can be adopted as the following can be adopted.

[0050] m1 is an integer of 0 to 3.

[0051] The compound represented by the above general formula (a) or (b) preferably contains at least one atom of N, P, and S. When the compound represented by the general formula (a) or (b) contains N, it is preferable that this N is present as an amino group. When the compound represented by the general formula (a) or (b) contains P, it is preferable that this P is present as a phosphate group (phosphoric acid group) or a phosphonate group (phosphonic acid group). When the compound represented by the general formula (a) or (b) contains S, it is preferable that this S is present as a sulfonyl group (-SO ２ In addition, the compound represented by the general formula (a) or (b) preferably has R ２ａ The compound has an acyl group as the group, i.e., OR ２ａIt is also preferred that the alkyl group has an acetate structure as described below.

[0052] Specific examples of the titanium alkoxide compound used in the present invention are listed below, but the present invention is not limited to these. Isopropyl triisostearoyl titanate, Isopropyl tridodecylbenzenesulfonyl titanate, Isopropyl trioctanoyl titanate, Isopropyl tri(dioctyl phosphite) titanate, Isopropyl tris(dioctyl pyrophosphate) titanate, Isopropyl tri(dioctyl sulfate) titanate, Isopropyl tricumyl phenyl titanate, Isopropyl tri(N-aminoethyl-aminoethyl) titanate, Isopropyl dimethacryl isostearoyl titanate, Isopropyl isostearoyl diacryl titanate, Isobutyl trimethyl titanate, Diisostearoyl ethylene titanate, Diisopropyl bis(dioctyl pyrophosphate) titanate, Dioctyl bis(ditridecyl phosphate) titanate, Dicumyl phenyl oxyacetate titanate, Bis(dioctyl pyrophosphate) oxyacetate titanate Bis(dioctylpyrophosphate)ethylene titanate, Tetraisopropyl titanate, Tetrabutyl titanate, Tetraoctyl titanate, Tetrastearyl titanate, Tetraisopropylbis(dioctylphosphite)titanate, Tetraoctylbis(di-tridecylphosphite)titanate, Tetra(2,2-diallyloxymethyl-1-butyl)bis(di-tridecyl)phosphite titanate, Butyl titanate dimer, Titanium tetraacetylacetonate, Titanium ethylacetoacetate, Titanium octylene glycolate, Titanium di-2-ethylhexoxybis(2-ethyl-3-hydroxyhexoxide)

[0053] (Aluminum Alkoxide Compound) As the aluminum alkoxide compound (preferably an aluminum coupling agent) used in the present invention, a wide range of ordinary aluminum alkoxide compounds that can be used as a primer layer for components of an acoustic wave probe can be used.

[0054] The aluminum alkoxide compound preferably contains at least one compound represented by the following general formula (c) or (d), and more preferably contains at least one compound represented by the following general formula (c): The total content of the compounds represented by the following general formula (c) or (d) in the aluminum alkoxide compound is not particularly limited and can be, for example, 60% by mass or more, preferably 80% by mass or more, more preferably 90% by mass or more, even more preferably 95% by mass or more, or even 100% by mass.

[0055] General formula (c): R １ｂ ｍ２ -Al-(OR ２ｂ ) ３－ｍ２ General formula (d): O-[Al-(OR ２ｂ ) ２ ] ２

[0056] R １ｂ represents a hydrogen atom, an alkyl group, a cycloalkyl group, an acyl group, an aryl group, or an unsaturated aliphatic group. １ｂ The alkyl group that can be taken as R includes a linear alkyl group, a branched alkyl group, and an aralkyl group. The number of carbon atoms in this alkyl group is preferably 1 to 20, more preferably 1 to 15, even more preferably 1 to 10, and particularly preferably 1 to 8, and in the case of an aralkyl group, it is preferably 7 to 30. Specific preferred examples of this alkyl group include methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, isobutyl, tert-butyl, pentyl, hexyl, heptyl, octyl, decyl, tridecyl, octadecyl, benzyl, and phenethyl. R １ｂ The alkyl group that can be taken as R preferably has an oxirane ring, for example, R １ｂ Examples of R include an epoxycycloalkyl group. １ｂThe number of ring members in the cycloalkyl group (a cycloalkyl group condensed with oxacyclopropane, which is an oxirane ring) in the epoxycycloalkyl group that can be taken as R is preferably 4 to 8, more preferably 5 or 6, and even more preferably 6 (i.e., the epoxycycloalkyl group is an epoxycyclohexyl group). １ｂ The alkyl group that can be taken as the alkyl group preferably has a group selected from an amino group, an isocyanato group, a mercapto group, an ethylenically unsaturated group, and an acid anhydride group.

[0057] R １ｂ The number of carbon atoms in the cycloalkyl group that can be taken as the aryl group is preferably 3 to 20, more preferably 3 to 15, even more preferably 3 to 10, and particularly preferably 3 to 8. Specific preferred examples of this cycloalkyl group include cyclopropyl, cyclopentyl, and cyclohexyl.

[0058] R １ｂ The number of carbon atoms in the acyl group that can be taken as the alkyl group is preferably 2 to 40, more preferably 2 to 30, even more preferably 2 to 20, and particularly preferably 2 to 18.

[0059] R １ｂ The number of carbon atoms in the aryl group that can be taken as (R) is preferably 6 to 20, more preferably 6 to 15, even more preferably 6 to 12, and particularly preferably 6 to 10. Specific preferred examples of this aryl group include phenyl and naphthyl, and phenyl is more preferred.

[0060] R １ｂ The number of carbon-carbon unsaturated bonds in the unsaturated aliphatic group that can be taken as above is preferably 1 to 5, more preferably 1 to 3, even more preferably 1 or 2, and particularly preferably 1. The unsaturated aliphatic group may contain a heteroatom, and is also preferably a hydrocarbon group. When the unsaturated aliphatic group is a hydrocarbon group, the number of carbon atoms is preferably 2 to 20, more preferably 2 to 15, even more preferably 2 to 10, still more preferably 2 to 8, and also preferably 2 to 5. The unsaturated aliphatic group is more preferably an alkenyl group or an alkynyl group.

[0061] R １ｂis preferably a hydrogen atom, an alkyl group, a cycloalkyl group, or an aryl group, and more preferably an alkyl group or a cycloalkyl group. １ｂ If there are two or more R １ｂ may be linked to each other to form a ring.

[0062] R ２ｂ represents a hydrogen atom, an alkyl group, a cycloalkyl group, an acyl group, an alkenyl group, an aryl group, a phosphonate group (phosphonic acid group), or —SO ２ R Ｓ２ Indicates. Ｓ２ represents a substituent. ２ｂ The alkyl group, cycloalkyl group, acyl group, and aryl group that can be taken as R １ｂ The alkyl group, cycloalkyl group, acyl group, and aryl group that can be taken as R are the same as those, and the preferred forms of each group are also the same. ２ｂ The alkyl group which can be taken as the alkyl group preferably has an amino group as a substituent.

[0063] R ２ｂ The alkenyl group that can be taken as (R) includes a linear alkenyl group and a branched alkenyl group. The number of carbon atoms in this alkenyl group is preferably 2 to 18, more preferably 2 to 7, and even more preferably 2 to 5. Specific preferred examples of this alkenyl group include vinyl, allyl, butenyl, pentenyl, and hexenyl. The alkenyl group is preferably a substituted alkenyl group.

[0064] R ２ｂ The phosphonate group that can be taken as is -P(=O)(-OR Ｐ１ ) OR Ｐ２ R is a group represented by the formula: Ｐ１ and R Ｐ２ represents a hydrogen atom or a substituent, and the substituent is preferably an alkyl group or a phosphonate group. Ｐ１ and R Ｐ２ The alkyl group that can be taken as R １ｂ The preferred alkyl groups are also the same as those of the alkyl groups R Ｐ１ and R Ｐ２Possible phosphonate groups are R ２ｂ The meanings and preferred forms of the phosphonate groups are the same as those of the phosphonate groups represented by R Ｐ１ or R Ｐ２ is a phosphonate group, R constituting this phosphonate group Ｐ１ and R Ｐ２ is preferably an alkyl group. ２ｂ Possible phosphonate groups are R Ｐ１ and R Ｐ２ are both alkyl groups, or R Ｐ１ is a hydrogen atom, and R Ｐ２ is preferably a phosphonate group. Note that, since a phosphonate group is tautomeric with a phosphite group (phosphorous acid group), the phosphonate group in the present invention is meant to include a phosphite group.

[0065] R ２ｂ It can be taken as -SO ２ R Ｓ２ In the formula, the substituent R Ｓ２ is preferably an alkyl group or an aryl group. Ｓ２ As preferred forms of the alkyl group and aryl group that can be taken as R １ｂ Among them, R Ｓ２ is preferably a phenyl having an alkyl group as a substituent. The preferred form of this alkyl group is the above-mentioned R １ｂ The preferred forms of the alkyl group are the same as those of the alkyl group that can be taken as above.

[0066] The compound represented by general formula (c) is R ２ｂ If there are two or more R ２ｂ In the compound represented by general formula (d), two R ２ｂ may be linked to each other to form a ring.

[0067] m2 is an integer of 0 to 2.

[0068] In the above general formulas (c) and (d), OR ２ｂIt is preferable that at least one of the above has an acetonato structure. This acetonato structure means a structure in which one hydrogen ion is removed from acetone or a compound having a structure in which acetone has a substituent, and the hydrogen ion is coordinated to Al. The coordinating atom that coordinates to this Al is usually an oxygen atom. This acetonato structure is an acetylacetone structure ("CH ３ —C(═O)—CH ２ —C(═O)—CH ３ ") from which one hydrogen ion has been removed, leaving an oxygen atom as a coordinating atom coordinated to Al (i.e., an acetylacetonato structure). The above phrase "having an acetylacetone structure as a basic structure" means not only the above acetylacetone structure, but also structures in which the hydrogen atoms of the above acetylacetone structure have been substituted with substituents. OR ２ｂ In the above general formulas (c) and (d), examples of a form in which OR ２ｂ It is preferable that at least one of the above has an acetate structure. In the present invention, the acetate structure means a structure in which one hydrogen ion is removed from acetic acid or an acetate ester, or a compound having a structure in which these have a substituent (including a form in which the methyl group of acetic acid has an alkyl group as a substituent), and the resulting structure is coordinated to Al. The coordinating atom coordinated to this Al is usually an oxygen atom. This acetate structure is an alkylacetoacetate structure ("CH ３ —C(═O)—CH ２ -C(=O)-OR ａｌｋ ” (R ａｌｋ represents an alkyl group (preferably an alkyl group having 1 to 20 carbon atoms, which may be an alkyl group having 1 to 10 carbon atoms, and more preferably an alkyl group having 1 to 4 carbon atoms). )) is a basic structure from which one hydrogen ion has been removed, and an oxygen atom is coordinated to Al as a coordinating atom (i.e., an alkylacetoacetate structure). The above phrase "having an alkylacetoacetate structure as a basic structure" means that in addition to the above alkylacetoacetate structure, it also includes structures in which the hydrogen atoms of the above alkylacetoacetate structure have been substituted with substituents. OR ２ｂExamples of compounds having an acetato structure include compounds AL-2, AL-3, and AL-4, which will be described later.

[0069] The above R １ｂ or R ２ｂ Each of the groups that can be taken as may have an anionic group (salt-type substituent) having a counter cation as a substituent. An anionic group refers to a group that can form an anion. An example of the anionic group having a counter cation is a carboxylate ion group having an ammonium ion as a counter cation. In this case, the counter cation may be present in the compound represented by the above general formula (c) or (d) so that the overall charge of the compound is 0. This also applies to the compounds represented by the above general formula (a) or (b) and the compounds represented by the below-described general formula (e) or (f).

[0070] Specific examples of the aluminum alkoxide compound used in the present invention are listed below, but the present invention is not limited to these. Aluminum triethylate, Aluminum triisopropylate, Aluminum trisec-butylate, Aluminum tris(ethylacetoacetate), Ethylacetoacetate aluminum diisopropylate, Aluminum monoacetylacetonate bis(ethylacetoacetate), Aluminum tris(acetylacetonate), Diisopropoxyaluminum-9-octadecenylacetoacetate, Aluminum diisopropoxymonoethylacetoacetate, Monosec-butoxyaluminum diisopropylate, Diethylacetoacetate aluminum isopropylate, Aluminum bis(ethylacetoacetate) monoacetylacetonate, Aluminum octadecylacetoacetate diisopropylate

[0071] (Zirconium Alkoxide Compound) As the zirconium alkoxide compound (preferably a zirconium coupling agent) used in the present invention, a wide range of ordinary zirconium alkoxide compounds that can be used as primer layers for constituent members of acoustic wave probes can be used.

[0072] The zirconium alkoxide compound preferably contains at least one compound represented by the following general formula (e) or (f), and more preferably contains at least one compound represented by the following general formula (e): The total content of the compounds represented by the following general formula (e) or (f) in the zirconium alkoxide compound is not particularly limited and can be, for example, 60% by mass or more, preferably 80% by mass or more, more preferably 90% by mass or more, even more preferably 95% by mass or more, or even 100% by mass.

[0073] General formula (e): R １ｃ ｍ３ -Zr-(OR ２ｃ ) ４－ｍ３ General formula (f): O-[Zr-(OR ２ｃ ) ３ ] ２

[0074] R １ｃ represents a hydrogen atom, an alkyl group, a cycloalkyl group, an acyl group, an aryl group, or an unsaturated aliphatic group. １ｃ Examples of the alkyl group, cycloalkyl group, acyl group, aryl group and unsaturated aliphatic group that can be taken as R １ｂ Examples of the alkyl group, cycloalkyl group, acyl group, aryl group and unsaturated aliphatic group that can be taken as the alkyl group include alkyl, cycloalkyl, acyl, aryl and unsaturated aliphatic groups.

[0075] R ２ｃ is a hydrogen atom, an alkyl group, a cycloalkyl group, an acyl group, an alkenyl group, an aryl group, a phosphonate group, or —SO ２ R Ｓ３ Indicates. Ｓ３ represents a substituent. ２ｃ Examples of the alkyl group, cycloalkyl group, acyl group, alkenyl group, aryl group and phosphonate group that can be taken as R ２ｂ The alkyl group, cycloalkyl group, acyl group, alkenyl group, aryl group and phosphonate group that can be taken as R Ｓ３ Examples of the substituents that can be adopted as the substituent include R Ｓ２The substituents that can be adopted as the following can be adopted.

[0076] m3 is an integer of 0 to 3.

[0077] In the above general formulas (e) and (f), OR ２ｃ Preferably, at least one of the following has an acetonate structure. This acetonate structure has the same meaning as the acetonate structure explained in general formula (c). OR ２ｃ In the above general formula (e), examples of compounds having an acetonato structure include compounds ZR-1 and ZR-3, which will be described later. ２ｃ Preferably, at least one of the following has an acetato structure. This acetato structure has the same meaning as the acetato structure described in general formula (c). OR ２ｃ In the above general formulas (e) and (f), an example of a form in which OR ２ｃ Preferably, at least one of the above has a lactato structure. This lactato structure means a structure in which a lactate ion (lactate) is used as a basic structure, from which one hydrogen ion has been removed and coordinated to Zr. The above phrase "having a lactate ion as a basic structure" means that in addition to the lactate ion, it also includes a structure in which the hydrogen atom of the lactate ion is substituted with a substituent. The coordinating atom coordinated to this Zr is usually an oxygen atom. OR ２ｃ An example of a compound having a lactato structure is Compound ZR-2, which will be described later.

[0078] Specific examples of the zirconium alkoxide compound used in the present invention are listed below, but the present invention is not limited to these. Tetrapropoxyzirconium (also known as zirconium tetra-n-propoxide) Tetrabutoxyzirconium (also known as zirconium tetra-n-butoxide) Zirconium tetraacetylacetonate Zirconium tributoxymonoacetylacetonate Zirconium dibutoxybis(acetylacetonate) Zirconium dibutoxybis(ethylacetoacetate) Zirconium tributoxyethylacetoacetate Zirconium monobutoxyacetylacetonate bis(ethylacetoacetate) Zirconium tributoxymonostearate (also known as zirconium stearate tri-n-butoxide) Zirconium stearate Zirconium lactate ammonium salt Zirconium monoacetylacetonate

[0079] The molecular weight of the silane coupling agent, titanium alkoxide compound, aluminum alkoxide compound, and zirconium alkoxide compound used in the present invention is not particularly limited, and is, for example, preferably 100 to 2000, more preferably 200 to 500. Polymeric silane coupling agents can also be used.

[0080] The silane coupling agent, aluminum alkoxide compound, zirconium alkoxide compound, and titanium alkoxide compound that can be contained in the intermediate layer may each be one type or two or more types.

[0081] When the intermediate layer contains at least one component derived from a silane coupling agent, a titanium alkoxide compound, an aluminum alkoxide compound, and a zirconium alkoxide compound, the total content of the components derived from the silane coupling agent, the titanium alkoxide compound, the aluminum alkoxide compound, and the zirconium alkoxide compound contained in the intermediate layer is not particularly limited, but is preferably 1% by mass or more, more preferably 5% by mass or more, even more preferably 10% by mass or more, and particularly preferably 15% by mass or more. There is no particular upper limit, and for example, it is preferably 99% by mass or less, more preferably 95% by mass or less, and even more preferably 90% by mass or less. That is, the total content of the components derived from the silane coupling agent, the titanium alkoxide compound, the aluminum alkoxide compound, and the zirconium alkoxide compound contained in the intermediate layer is preferably 1 to 99% by mass, more preferably 5 to 99% by mass, even more preferably 10 to 95% by mass, and particularly preferably 15 to 90% by mass. The total content of the silane coupling agent, titanium alkoxide compound, aluminum alkoxide compound, and zirconium alkoxide compound in the liquid (including solvent) used to form the intermediate layer is, for example, preferably 0.02% by mass or more, more preferably 0.1% by mass or more, even more preferably 0.3% by mass or more, and particularly preferably 0.5% by mass or more. There is no particular upper limit, and it is, for example, 99% by mass or less, preferably 70% by mass or less, more preferably 50% by mass or less, and even more preferably 25% by mass or less. That is, the total content of the silane coupling agent, titanium alkoxide compound, aluminum alkoxide compound, and zirconium alkoxide compound in the liquid (including solvent) used to form the intermediate layer is preferably 0.02 to 99% by mass, more preferably 0.1 to 70% by mass, even more preferably 0.3 to 50% by mass, and particularly preferably 0.5 to 25% by mass.

[0082] In the present invention, the phrase "the intermediate layer contains a component derived from at least one of a silane coupling agent, a titanium alkoxide compound, an aluminum alkoxide compound, and a zirconium alkoxide compound" means that it encompasses forms in which at least one of a silane coupling agent, a titanium alkoxide compound, an aluminum alkoxide compound, and a zirconium alkoxide compound is contained in a state in which it has reacted with the acoustic lens layer and / or the substrate. For example, the silane coupling agent, the titanium alkoxide compound, the aluminum alkoxide compound, and the zirconium alkoxide compound are at least partially hydrolyzed to expose hydroxy groups, which may then react with groups on the surface of the acoustic lens layer and / or the substrate.

[0083] The intermediate layer may contain components other than the siloxane compound having a component derived from a hydrolyzed silicate compound, and the component derived from at least one of a silane coupling agent, a titanium alkoxide compound, an aluminum alkoxide compound, and a zirconium alkoxide compound, as long as the effects of the present invention are not impaired, and examples of such components include additives such as surfactants, antioxidants, thickeners, leveling agents, stabilizers, and antifoaming agents. The intermediate layer may be a single layer or multiple layers, and is preferably a single layer.

[0084] The average thickness of the intermediate layer is not particularly limited, and is, for example, preferably 5 nm to 100 μm, more preferably 10 nm to 20 μm, even more preferably 25 nm to 10 μm, and particularly preferably 40 nm to 5 μm. The average thickness of the intermediate layer is a value measured by the method described in the Examples below.

[0085] <Acoustic Lens Layer> The acoustic lens layer in the acoustic wave probe of the present invention is a layer formed by curing a room-temperature-curable silicone, and this room-temperature-curable silicone contains a structural unit having a phenyl group. As described above, by using a room-temperature-curable silicone having a structural unit having a phenyl group as the acoustic lens layer in the acoustic wave probe of the present invention, the permeability of hydrogen peroxide gas and the like through the acoustic lens layer is suppressed, and the amount of hydrogen peroxide gas and the like that reaches the interface between the acoustic lens layer and the intermediate layer, and further the interface between the intermediate layer and the substrate, is reduced, which is thought to result in excellent resistance to hydrogen peroxide plasma sterilization.

[0086] The phenyl group content in the cured product of the room-temperature-curable silicone is preferably 1 to 50 mol%, more preferably 2 to 30 mol%, and from the viewpoint of superior heat cycle resistance and hydrogen peroxide plasma sterilization resistance, is even more preferably 3 to 20 mol%, and particularly preferably 4 to 10 mol%. The phenyl groups in the cured product of the room-temperature-curable silicone may be unsubstituted or may have a substituent. Examples of substituted phenyl groups include alkyl-substituted phenyl groups (referring to a group in which a hydrogen atom in a phenyl group is substituted with a linear, branched, or cyclic alkyl group having 1 to 10 carbon atoms), and groups in which a hydrogen atom in a phenyl group is substituted with at least one substituent selected from the group consisting of a halogen atom, a hydroxy group, an alkoxy group, an alkoxyalkyl group, an alkoxycarbonyl group, an alkoxycarbonyloxy group, a carboxy group, a cyano group, and a nitro group. Here, the content of phenyl groups in the cured product of room-temperature-curable silicone refers to the mol % of phenyl-group-containing siloxane units when all units constituting the cured product of room-temperature-curable silicone are taken as 100 mol %. One phenyl-group-containing siloxane unit has 1 to 3 phenyl groups. Of these, two phenyl groups per phenyl-group-containing siloxane unit is preferred. For example, when all Si atoms in the Si-O units and terminal Si have at least one phenyl group, the total is 100 mol %. Note that the unit refers to the Si-O units and terminal Si.

[0087] Room temperature curable silicone, also known as RTV silicone, refers to a silicone that can be cured at temperatures of 50° C. or less. For example, a silicone composition containing a vinyl silicone and a hydrosilicone can be used as an RTV silicone and is preferably used because it can be cured at temperatures of 50° C. or less in the presence of a platinum catalyst.

[0088] (Silicone Composition) A silicone composition containing a vinyl silicone and a hydrosilicone, which are room-temperature curable silicones (also referred to simply as a "silicone composition" in the present invention), contains a vinyl silicone, which is a polysiloxane having a vinyl group, and a hydrosilicone, which is a polysiloxane having two or more Si—H groups in the molecular chain. Note that it is sufficient that the structural unit having a phenyl group is contained as a structural unit of at least one of the vinyl silicone and the hydrosilicone, and it is preferably contained as a structural unit of at least the vinyl silicone.

[0089] The content of the vinyl silicone is preferably 80 to 99.9 parts by mass, and the content of the hydrosilicone is preferably 0.1 to 20 parts by mass, based on a total of 100 parts by mass of the silicone composition. When the silicone composition contains components other than the vinyl silicone and the hydrosilicone, the content of the vinyl silicone is more preferably 40 to 70 parts by mass, and even more preferably 45 to 65 parts by mass. The content of the hydrosilicone is more preferably 0.3 to 15 parts by mass, even more preferably 0.3 to 10 parts by mass, particularly preferably 0.4 to 5 parts by mass, and of these, 0.4 to 3 parts by mass is preferred.

[0090] From the viewpoints of further suppressing the permeability of hydrogen peroxide gas and the like through the acoustic lens layer and further improving resistance to hydrogen peroxide plasma sterilization, the silicone composition preferably contains surface-treated oxide particles, as described below, and more preferably surface-treated spherical silica particles, as described below. When the silicone composition contains surface-treated oxide particles, the preferred contents of each component are as follows: For a total of 100 parts by mass of the silicone composition, the content of the vinyl silicone is preferably 29.9 to 74.9 parts by mass, and the content of the hydrosilicone is preferably 0.1 to 20 parts by mass. The content of the vinyl silicone is more preferably 40 to 70 parts by mass, and even more preferably 45 to 65 parts by mass. The content of the hydrosilicone is more preferably 0.3 to 15 parts by mass, even more preferably 0.3 to 10 parts by mass, particularly preferably 0.4 to 5 parts by mass, and of these, 0.4 to 3 parts by mass is preferred. The content of the surface-treated oxide particles (preferably surface-treated spherical silica particles) in a total of 100 parts by mass of the silicone composition is preferably 25 to 70 parts by mass, more preferably 30 to 60 parts by mass, and even more preferably 35 to 50 parts by mass. When the content of the surface-treated oxide particles (preferably surface-treated spherical silica particles) is within the above range, tear strength, flexural durability, and acoustic wave sensitivity are enhanced. When the content of the polysiloxane (vinyl silicone and hydrosilicone) is within the above range, the resulting cured product (silicone resin) has an excellent balance of hardness, tear strength, and acoustic impedance. The silicone composition is a composition that does not contain a catalyst that crosslinks and polymerizes (cures) the vinyl silicone and hydrosilicone. Therefore, the silicone composition contains silica particles but does not contain a catalyst. Furthermore, a total of 100 parts by mass of the silicone composition means that the sum of the individual components contained in the silicone composition is 100 parts by mass.

[0091] The silicones contained in the silicone composition may be any silicone as long as they have a vinyl group and two or more Si—H groups in the molecular chain. However, in the present invention, the vinyl silicone is preferably the polyorganosiloxane (A) having a vinyl group described below, and the hydrosilicone is preferably the polyorganosiloxane (B) having two or more Si—H groups in the molecular chain described below. The structural unit having a phenyl group may be contained as a structural unit in at least one of the polyorganosiloxane (A) having a vinyl group and the polyorganosiloxane (B) having two or more Si—H groups in the molecular chain, and is preferably contained as a structural unit in at least the polyorganosiloxane (A) having a vinyl group. Therefore, in the present invention, a composition containing at least a polyorganosiloxane (A) having a vinyl group and a polyorganosiloxane (B) having two or more Si—H groups in the molecular chain as components in the silicone composition is preferred, and a composition containing at least a polyorganosiloxane (A) having a vinyl group, a polyorganosiloxane (B) having two or more Si—H groups in the molecular chain, and silica particles (C) as components is more preferred. In the detailed description below, a preferred embodiment of the silicone composition will be described, in which the silicone composition contains a polyorganosiloxane (A) having a vinyl group and a polyorganosiloxane (B) having two or more Si—H groups in the molecular chain. However, the silicones contained in the silicone composition are not limited to these polyorganosiloxanes (A) and (B).

[0092] (Polyorganosiloxane (A) having vinyl groups) The polyorganosiloxane (A) having vinyl groups used in the present invention (hereinafter also simply referred to as polyorganosiloxane (A)) preferably has two or more vinyl groups in the molecular chain. As the polyorganosiloxane (A), for example, polyorganosiloxane (a) (hereinafter also simply referred to as polyorganosiloxane (a)) having vinyl groups at least at both ends of the molecular chain, or -O-Si(CH ３ ) ２ (CH=CH ２) at least two (hereinafter, also referred to simply as polyorganosiloxane (b)). Among them, polyorganosiloxane (a) having vinyl groups at both ends of the molecular chain is preferred. The polyorganosiloxane (a) is preferably linear, and the polyorganosiloxane (b) is preferably a polyorganosiloxane having a vinyl group at both ends of the molecular chain. ３ ) ２ (CH=CH ２ ) is preferably bonded to a Si atom constituting the main chain.

[0093] Polyorganosiloxane (A) is hydrosilylated by reaction with polyorganosiloxane (B) having two or more Si—H groups in the presence of, for example, a platinum catalyst. This hydrosilylation reaction (addition reaction) forms a crosslinked structure (cured product).

[0094] The vinyl group content of polyorganosiloxane (A) is not particularly limited. From the viewpoint of forming a sufficient network with each component contained in the acoustic lens layer, for example, the vinyl group content is preferably 0.01 to 5 mol%, more preferably 0.05 to 2 mol%. Here, the vinyl group content refers to the mol% of vinyl group-containing siloxane units when all units constituting polyorganosiloxane (A) are taken as 100 mol%. One vinyl group-containing siloxane unit has 1 to 3 vinyl groups. Of these, one vinyl group per vinyl group-containing siloxane unit is preferred. For example, when all Si atoms of the Si—O units constituting the main chain and the terminal Si have at least one vinyl group, the total is 100 mol%.

[0095] Furthermore, the polyorganosiloxane (A) preferably has a phenyl group. From the viewpoint of mechanical strength and hydrogen peroxide plasma sterilization resistance when formed into an acoustic lens layer, the phenyl group content is, for example, preferably 1 to 50 mol%, more preferably 2 to 30 mol%, and even more preferably 3 to 20 mol%. From the viewpoint of better heat cycle resistance and hydrogen peroxide plasma sterilization resistance, 4 to 10 mol% is particularly preferred. Here, the phenyl group content refers to the mol% of phenyl group-containing siloxane units when all units constituting the polyorganosiloxane (A) are taken as 100 mol%. One phenyl group-containing siloxane unit has 1 to 3 phenyl groups. In particular, two phenyl groups are preferred for one phenyl group-containing siloxane unit. For example, when all Si atoms of the Si-O units constituting the main chain and the terminal Si have at least one phenyl group, the content is 100 mol%. The unit refers to the Si--O unit constituting the main chain and the terminal Si.

[0096] The degree of polymerization and specific gravity are not particularly limited. From the standpoint of improving the mechanical strength, hardness, chemical stability, etc. of the silicone resin (hereinafter also simply referred to as silicone resin) that constitutes the resulting acoustic lens layer, the degree of polymerization is preferably 200 to 3,000, more preferably 400 to 2,000, and the specific gravity is preferably 0.9 to 1.1.

[0097] The mass average molecular weight of the polyorganosiloxane (A) is preferably 20,000 to 200,000, more preferably 40,000 to 150,000, and even more preferably 45,000 to 120,000, from the viewpoints of mechanical strength, hardness, and / or ease of processing.

[0098] In the present invention, the mass average molecular weight can be measured using, for example, a GPC apparatus HLC-8220 (trade name, manufactured by Tosoh Corporation), toluene (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as an eluent, TSKgel (registered trademark) G3000HXL + TSKgel (registered trademark) G2000HXL as columns, under conditions of a temperature of 23°C and a flow rate of 1 mL / min, using an RI (differential refractive index) detector.

[0099] The kinematic viscosity of the polyorganosiloxane (A) at 25°C is 1 x 10 －５ ~10m ２ / s is preferred, and 1 × 10 －４ ~1m ２ / s is more preferable, and 1 × 10 －３ ~0.5m ２ The kinematic viscosity can be determined in accordance with JIS Z8803 by measuring at a temperature of 25°C using an Ubbelohde viscometer (for example, manufactured by Shibata Chemical Industries, Ltd., trade name: SU).

[0100] The polyorganosiloxane (a) having vinyl groups at least at both molecular chain terminals is preferably a polyorganosiloxane represented by the following general formula (A).

[0101]

[0102] In general formula (A), R ａ１ represents a vinyl group, and R ａ２ and R ａ３ each independently represents an alkyl group, a cycloalkyl group, an alkenyl group, or an aryl group, and x1 and x2 each independently represents an integer of 1 or more.

[0103] R ａ２ and R ａ３ The number of carbon atoms in the alkyl group is preferably 1 to 10, more preferably 1 to 4, still more preferably 1 or 2, and particularly preferably 1. Examples of the alkyl group include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, n-hexyl, n-octyl, 2-ethylhexyl, and n-decyl.

[0104] R ａ２ and R ａ３ The number of carbon atoms in the cycloalkyl group is preferably 3 to 10, more preferably 5 to 10, and even more preferably 5 or 6. The cycloalkyl group is preferably a 3-, 5-, or 6-membered ring, and more preferably a 5- or 6-membered ring. Examples of the cycloalkyl group include cyclopropyl, cyclopentyl, and cyclohexyl.

[0105] R ａ２ and Rａ３ The number of carbon atoms in the alkenyl group in the formula (I) is preferably 2 to 10, more preferably 2 to 4, and even more preferably 2. Examples of the alkenyl group include vinyl, allyl, and butenyl.

[0106] R ａ２ and R ａ３ The number of carbon atoms in the aryl group in the formula (I) is preferably 6 to 12, more preferably 6 to 10, and even more preferably 6 to 8. Examples of the aryl group include phenyl, tolyl, and naphthyl.

[0107] These alkyl groups, cycloalkyl groups, alkenyl groups, and aryl groups may have a substituent. Such substituents include, for example, halogen atoms, alkyl groups, cycloalkyl groups, alkenyl groups, aryl groups, alkoxy groups, aryloxy groups, alkylthio groups, arylthio groups, silyl groups, and cyano groups. Examples of groups having a substituent include halogenated alkyl groups.

[0108] R ａ２ and R ａ３ is preferably an alkyl group, an alkenyl group, or an aryl group, more preferably an alkyl group having 1 to 4 carbon atoms, a vinyl group, or a phenyl group, still more preferably a methyl group, a vinyl group, or a phenyl group, and particularly preferably a methyl group or a phenyl group. Among these, when the polyorganosiloxane (a) having vinyl groups at least at both ends of the molecular chain contains a structural unit having a phenyl group, ( ) ｘ２ In the repeating unit represented by ａ２ and R ａ３ are both phenyl groups, and the other R ａ２ is a methyl group, ie, a vinyl-terminated diphenylsiloxane-dimethylsiloxane copolymer.

[0109] x1 is preferably an integer of 200 to 3,000, more preferably an integer of 400 to 2,000. x2 is preferably an integer of 1 to 3,000, more preferably an integer of 1 to 1,000, even more preferably an integer of 40 to 1,000, and particularly preferably an integer of 40 to 700. In another embodiment, x1 is preferably an integer of 1 to 3,000, more preferably an integer of 5 to 1,000.

[0110] Examples of polyorganosiloxanes having vinyl groups at at least both molecular chain terminals are trade names manufactured by Gelest, including the DMS series (e.g., DMS-V31, DMS-V31S15, DMS-V33, DMS-V35, DMS-V35R, DMS-V41, DMS-V42, DMS-V46, DMS-V51, and DMS-V52), the PDV series (e.g., PDV-0341, PDV-0346, PDV-0535, PDV-0541, PDV-1631, PDV-1635, PDV-1641, and PDV-2335), PMV-9925, PVV-3522, FMV-4031, and EDV-2022. Since DMS-V31S15 is pre-blended with fumed silica, kneading using a special device is not required.

[0111] The vinyl group-containing polyorganosiloxane (A) in the present invention may be used alone or in combination of two or more kinds.

[0112] (Polyorganosiloxane (B) having two or more Si—H groups in the molecular chain) The polyorganosiloxane (B) having two or more Si—H groups in the molecular chain used in the present invention (hereinafter also simply referred to as polyorganosiloxane (B)) has two or more Si—H groups in the molecular chain. Here, when component (b) is "-SiH ２ -" structure, "-SiH ２ The number of Si-H groups in the "-" structure is counted as two. ３ " structure, "-SiH ３The number of Si-H groups in the " structure is counted as three. By having two or more Si-H groups in the molecular chain, it is possible to form a crosslinked structure by reacting with a polyorganosiloxane having a polymerizable unsaturated group (such as a vinyl group) (preferably a polyorganosiloxane having at least two polymerizable unsaturated groups (such as a vinyl group)).

[0113] The polyorganosiloxane (B) may have a linear structure or a branched structure, with the linear structure being preferred. The mass average molecular weight of the linear structure is preferably 500 to 100,000, more preferably 1,500 to 50,000, from the viewpoint of the mechanical strength and hardness of the acoustic lens layer.

[0114] The linear polyorganosiloxane (B) having two or more Si—H groups in the molecular chain is preferably a polyorganosiloxane represented by the following general formula (B).

[0115]

[0116] In general formula (B), R ｂ１ ~R ｂ３ are each independently a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, an aryl group, or —O—Si(R ｂ５ ) ２ (R ｂ４ ) represents. ｂ４ and R ｂ５ Each of R independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, or an aryl group. y1 represents an integer of 0 or more, and y2 represents an integer of 1 or more. ｂ１ , multiple R ｂ２ , multiple R ｂ３ , multiple R ｂ４ and multiple R ｂ５ may be the same or different from each other, and R ｂ１ ~R ｂ５ Each of the groups may be further substituted with a substituent, provided that the molecular chain contains two or more Si—H groups.

[0117] R ｂ１ ~R ｂ３ The alkyl group, cycloalkyl group, alkenyl group and aryl group in R ａ２ and Rａ３ The meanings and preferred ranges of the alkyl group, cycloalkyl group, alkenyl group and aryl group in the above formula are the same as those in the above formula.

[0118] —O—Si(R ｂ５ ) ２ (R ｂ４ ) R ｂ４ and R ｂ５ The alkyl group, cycloalkyl group, alkenyl group and aryl group in R ｂ１ ~R ｂ３ The meanings and preferred ranges of the alkyl group, cycloalkyl group, alkenyl group and aryl group in the above formula are the same as those in the above formula.

[0119] R ｂ１ ~R ｂ３ is a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, or —O—Si(R ｂ５ ) ２ (R ｂ４ ), and a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a vinyl group, a phenyl group or —O—Si(CH ３ ) ２ H is more preferred. ｂ１ and R ｂ２ R is more preferably a hydrogen atom, an alkyl group, an alkenyl group, or an aryl group, even more preferably a hydrogen atom or an alkyl group, and particularly preferably a hydrogen atom or a methyl group. ｂ３ is more preferably a hydrogen atom or an aryl group, further preferably a hydrogen atom or a phenyl group, and particularly preferably a hydrogen atom.

[0120] In the present invention, R ｂ３ is a phenyl group, R ｂ１ is preferably a hydrogen atom, and more preferably R ｂ１ is a hydrogen atom and satisfies the following conditions: 1) one R in the repetition of y1 ｂ２ is a hydrogen atom, and the remaining R ｂ２ is an alkyl group, and R ｂ２ is an alkyl group, and R ｂ３ is a phenyl group 2) y1 is 0, and R in the repeat of y2 ｂ２ is an alkyl group, and Rｂ３ is a phenyl group 3) y1 is 0, and R in the repeat of y2 ｂ２ is —O—Si(R ｂ５ ) ２ (R ｂ４ ) and R ｂ３ is a phenyl group. In the above 3), R ｂ４ is a hydrogen atom and R ｂ５ is preferably an alkyl group.

[0121] y1 is preferably an integer of 0 to 2,000, more preferably an integer of 0 to 1,000, and even more preferably an integer of 0 to 30. y2 is preferably an integer of 1 to 2,000, more preferably an integer of 1 to 1,000, and even more preferably an integer of 1 to 30. y1+y2 is preferably an integer of 5 to 2,000, more preferably an integer of 7 to 1,000, even more preferably an integer of 10 to 50, and especially preferably an integer of 15 to 30. In the present invention, "-Si(R ｂ２ ) ２ -O-” and “-Si(R ｂ２ ) (R ｂ３ ) ２ Each of the —O— groups may be present in the polysiloxane in the form of a block polymer, or may be present randomly.

[0122] R ｂ１ ~R ｂ３ As a combination of ｂ１ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, R ｂ２ is an alkyl group having 1 to 4 carbon atoms, R ｂ３ is preferably a combination of hydrogen atoms, and R ｂ１ is an alkyl group having 1 to 4 carbon atoms, R ｂ２ is an alkyl group having 1 to 4 carbon atoms, R ｂ３ In this preferred combination, the content of hydrosilyl groups represented by y2 / (y1+y2) is preferably more than 0.1 and not more than 1.0, more preferably more than 0.2 and not more than 1.0. In other words, the embodiment in which y1 is 0 is also included.

[0123] Examples of the linear polyorganosiloxane (B) include HMS-064 (MeHSiO: 5-7 mol%), HMS-082 (MeHSiO: 7-8 mol%), HMS-301 (MeHSiO: 25-30 mol%), and HMS-501 (MeHSiO: 50-55 mol%), which are methylhydrosiloxane-dimethylsiloxane copolymers (trimethylsiloxane terminated), manufactured by Gelest Corporation; HPM-502 (MeHSiO: 45-50 mol%), which is a methylhydrosiloxane-phenylmethylsiloxane copolymer; and HMS-991 (MeHSiO: 100 mol%), which is a methylhydrosiloxane polymer. Here, the mol% of MeHSiO is the same as that of the above R ｂ１ ~R ｂ３ This is equivalent to multiplying y2 / (y1+y2) by 100 in the preferred combinations above.

[0124] In order to prevent the progression of crosslinking reactions within the molecule, both the linear structure and the branched structure preferably do not have a vinyl group, and in particular, those with a branched structure preferably do not have a vinyl group.

[0125] As the branched polyorganosiloxane (B) having two or more Si—H groups in the molecular chain, the description of the branched polyorganosiloxane described in

[0051] to

[0058] of WO 2017 / 130890 can be applied as is.

[0126] The polyorganosiloxane (B) having two or more Si—H groups in the molecular chain used in the present invention may be used alone or in combination of two or more. Also, a polyorganosiloxane (B) having a linear structure and a polyorganosiloxane (B) having a branched structure may be used in combination.

[0127] The vinyl groups of the polyorganosiloxane (A) and the Si—H groups of the polyorganosiloxane (B) usually react stoichiometrically at a ratio of 1: 1. However, from the viewpoint of reacting all the vinyl groups with the Si—H groups, the equivalent of the Si—H groups of the polyorganosiloxane (B) relative to the vinyl groups of the polyorganosiloxane (A) is preferably vinyl group:Si—H group=1:1.1 to 1:8, more preferably 1:1.2 to 1:5.

[0128] (Surface-treated oxide particles) As described above, the silicone composition preferably contains surface-treated oxide particles. Surface-treated oxide particles refer to particles obtained by surface-treating inorganic oxide particles. From the viewpoint of improving the acoustic impedance, hardness, and mechanical strength of the acoustic lens layer, the average primary particle diameter of the surface-treated oxide particles is preferably more than 3 nm and less than 500 nm, more preferably more than 16 nm and less than 250 nm, even more preferably 18 to 100 nm, particularly preferably 20 to 80 nm, and most preferably 25 to 70 nm.

[0129] Adding surface-treated oxide particles to the silicone composition improves the acoustic impedance, hardness, and mechanical strength of the resulting acoustic lens layer. In particular, when surface-treated oxide particles with an average primary particle diameter of more than 16 nm and less than 250 nm are used, it is possible to reduce the amount of acoustic wave attenuation and the viscosity before curing.

[0130] Here, the average primary particle size means the volume average particle size. This volume average particle size can be calculated, for example, by measuring the particle size distribution using a laser diffraction / scattering particle size distribution analyzer (e.g., Horiba, Ltd., product name "LA910"). In this specification, for particles whose average primary particle size is not listed in the catalog or for newly manufactured particles, the average primary particle size is the one determined by the above measurement method. Here, the average primary particle size of the surface-treated oxide particles means the average primary particle size in a surface-treated state.

[0131] Furthermore, the inorganic oxide particles constituting the surface-treated oxide particles are preferably particles of an inorganic oxide selected from silica, titanium oxide, aluminum oxide, zinc oxide, zirconium oxide, magnesium oxide, and calcium oxide, more preferably particles of an inorganic oxide selected from silica, titanium oxide, and zinc oxide, and even more preferably silica particles.

[0132] The surface-treated oxide particles may be used alone or in combination of two or more kinds.

[0133] The surface-treated oxide particles used in the present invention have a specific surface area of ​​1 to 400 m from the viewpoint of improving the hardness and / or mechanical strength of the resulting silicone resin. ２ / g is preferred, and 5 to 200m ２ / g is more preferable, and 10 to 100m ２ / g is particularly preferred.

[0134] The surface treatment method for the surface-treated oxide particles used in the present invention includes, for example, surface treatment with an inorganic compound and / or an organic compound, and surface treatment with a silane compound is preferred. For example, inorganic surface treatment with aluminum hydroxide, aluminum oxide, zirconium oxide, silica, and / or cerium oxide can be performed. Specific examples of organic surface treatment agents that can be used for surface treatment include silicone oils such as dimethylpolysiloxane, methylhydrogenpolysiloxane, (dimethicone / methicone) copolymer, methylphenylsilicone, amino-modified silicone, triethoxysilylethyl polydimethylsiloxyethyl dimethicone, and triethoxysilylethyl polydimethylsiloxyethylhexyl dimethicone; alkylsilanes such as caprylylsilane, decylsilane, and perfluorooctylsilane; alkyl titanates, alkylaluminates, polyolefins, polyesters, amino acids such as lauroyl lysine, polyamides, and their salts; metal soaps such as aluminum stearate, aluminum isostearate, and zinc stearate; and water-repellent resins such as nylon, polyester, and polyacrylic. Coupling agents such as silane coupling agents and titanium coupling agents can also be used. Surface treatment can be performed with at least one compound selected from these organic compounds. Furthermore, by performing additional surface treatments, inorganic and organic surface treatments can be combined. In particular, in order to improve dispersibility in the composition, it is very effective to apply an organic surface treatment.

[0135] Examples of surface treatment techniques with a silane compound include surface treatment with a silane coupling agent and coating with a silicone compound. (i) Silane Coupling Agent: From the viewpoint of improving the hardness and / or mechanical strength of the acoustic lens layer, a silane coupling agent having a hydrolyzable group is preferred. The hydrolyzable group in the silane coupling agent is hydrolyzed by water to form a hydroxyl group, which undergoes a dehydration condensation reaction with the hydroxyl group on the surface of the silica particles, thereby modifying the surface of the silica particles and improving the hardness and / or mechanical strength of the resulting silicone resin. Examples of hydrolyzable groups include alkoxy groups, acyloxy groups, and halogen atoms. Note that if the surface of the surface-treated oxide particles is modified to be hydrophobic, this is preferred because it improves the affinity between the surface-treated oxide particles and the polyorganosiloxanes (A) and (B) and improves resistance to hydrogen peroxide plasma sterilization.

[0136] Examples of silane coupling agents having a hydrophobic group such as an alkyl group or an aryl group as a reactive functional group include alkoxysilanes such as methyltrimethoxysilane (MTMS), dimethyldimethoxysilane, phenyltrimethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, hexyltrimethoxysilane, hexyltriethoxysilane, and decyltrimethoxysilane; chlorosilanes such as methyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane, and phenyltrichlorosilane; and hexamethyldisilazane (HMDS).

[0137] Examples of silane coupling agents having a vinyl group as a reactive functional group include alkoxysilanes such as methacryloyloxypropyltriethoxysilane, methacryloyloxypropyltrimethoxysilane, methacryloyloxypropylmethyldiethoxysilane, methacryloyloxypropylmethyldimethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, and vinylmethyldimethoxysilane; chlorosilanes such as vinyltrichlorosilane and vinylmethyldichlorosilane; and divinyltetramethyldisilazane.

[0138] The surface-treated oxide particles that are surface-treated with a silane coupling agent are preferably surface-treated oxide particles that are treated with a trialkylsilylating agent, and more preferably surface-treated oxide particles that are treated with a trimethylsilylating agent.Silane compounds include, for example, the above-mentioned silane coupling agents and the silane coupling agents in which a part of the alkoxy groups in the above-mentioned silane coupling agents are replaced with alkyl groups.In addition, trimethylsilylating agents include, for example, trimethylchlorosilane, hexamethyldisilazane (HMDS), methyltrimethoxysilane (MTMS) and the like described in the above-mentioned silane coupling agents, as well as trimethylmethoxysilane, which is a silane coupling agent in which a part of the alkoxy groups in the above-mentioned silane coupling agents are replaced with alkyl groups.

[0139] An example of a commercially available silane coupling agent is hexamethyldisilazane (HMDS) (for example, available under the trade name: HEXAMETHYLDISILAZANE (SIH6110.1), manufactured by Gelest). Hydroxyl groups present on the surface of oxide particles are covered with trimethylsilyl groups by reaction with hexamethyldisilazane (HMDS), methyltrimethoxysilane (MTMS), trimethylmethoxysilane, or the like, thereby modifying the surface of the silica particles to be hydrophobic. In the present invention, one type of silane coupling agent may be used alone, or two or more types may be used in combination.

[0140] (ii) Silicone Compound The silicone compound that coats the surface-treated oxide particles may be a polymer composed of siloxane bonds. Examples of silicone compounds include silicone compounds in which all or part of the side chains and / or terminals of polysiloxane are methyl groups, silicone compounds in which part of the side chains are hydrogen atoms, modified silicone compounds in which organic groups such as amino groups and / or epoxy groups are introduced into all or part of the side chains and / or terminals, and silicone resins with a branched structure. The silicone compound may have either a linear or cyclic structure.

[0141] Examples of silicone compounds in which all or part of the side chains and / or ends of the polysiloxane are methyl groups include monomethylpolysiloxanes such as polymethylhydrosiloxane (hydrogen terminal), polymethylhydrosiloxane (trimethylsiloxy terminal), polymethylphenylsiloxane (hydrogen terminal), and polymethylphenylsiloxane (trimethylsiloxy terminal), as well as dimethylpolysiloxanes such as dimethylpolysiloxane (hydrogen terminal), dimethylpolysiloxane (trimethylsiloxy terminal), and cyclic dimethylpolysiloxane.

[0142] Examples of silicone compounds in which part of the side chain is a hydrogen atom include methylhydrosiloxane-dimethylsiloxane copolymer (trimethylsiloxy terminated), methylhydrosiloxane-dimethylsiloxane copolymer (hydrogen terminated), polymethylhydrosiloxane (hydrogen terminated), polymethylhydrosiloxane (trimethylsiloxy terminated), polyethylhydrosiloxane (triethylsiloxy terminated), polyphenyl-(dimethylhydrosiloxy)siloxane (hydrogen terminated), methylhydrosiloxane-phenylmethylsiloxane copolymer (hydrogen terminated), methylhydrosiloxane-octylmethylsiloxane copolymer, and methylhydrosiloxane-octylmethylsiloxane-dimethylsiloxane terpolymer.

[0143] Furthermore, examples of modified silicones into which an organic group has been introduced include reactive silicones into which an organic group such as an amino group, an epoxy group, a methoxy group, a (meth)acryloyl group, a phenoxy group, a carboxylic anhydride group, a hydroxy group, a mercapto group, a carboxy group, and / or a hydrogen atom has been introduced, and non-reactive silicones modified with, for example, polyether, aralkyl, fluoroalkyl, long-chain alkyl, long-chain aralkyl, higher fatty acid ester, higher fatty acid amide, and / or polyether methoxy.

[0144] Silica particles coated with a silicone compound can be obtained by a conventional method. For example, they can be obtained by mixing and stirring silica particles in dimethylpolysiloxane for a certain period of time and then filtering. Furthermore, when a reactive modified silicone is used as the silicone compound, the organic group reacts with the hydroxyl group on the surface of the oxide particles, thereby modifying the surface of the oxide particles and improving the hardness and / or mechanical strength of the resulting acoustic lens layer.

[0145] An example of a commercially available silicone compound is methylhydrogensilicone oil (MHS) (trade name: KF-99, manufactured by Shin-Etsu Chemical Co., Ltd.), which is polymethylhydrosiloxane (trimethylsiloxy terminal).

[0146] The surface-treated oxide particles preferably have a methanol hydrophobicity of 40 to 80% by mass, more preferably 50 to 80% by mass, and even more preferably 60 to 80% by mass, as calculated by the following methanol titration test. Here, a higher methanol hydrophobicity indicates a higher hydrophobicity, while a lower methanol hydrophobicity indicates a higher hydrophilicity. 50 ml of ion-exchanged water and 0.2 g of sample surface-treated oxide particles are placed in a beaker, heated to 25°C, and stirred with a magnetic stirrer. Methanol is added dropwise from a buret, and the amount of methanol (X g) added until the entire sample sinks is measured. The methanol hydrophobicity is calculated using the following formula:

[0147] Methanol hydrophobicity (mass%) = 100% × X / (50 + X)

[0148] By ensuring that the methanol hydrophobicity is within the above preferred range, the viscosity of the silicone composition before curing does not increase, and a decrease in acoustic wave sensitivity when formed into an acoustic lens layer can be suppressed.

[0149] The Wardell sphericity of the primary particles of the surface-treated oxide particles is preferably 0.7 to 1, more preferably 0.8 to 1, and even more preferably 0.9 to 1. Here, "Wardell sphericity" (see Chemical Engineering Handbook, published by Maruzen Co., Ltd.) is an index measuring the sphericity of a particle by (diameter of a circle equal to the projected area of ​​the particle) / (diameter of the smallest circle circumscribing the projected image of the particle), and the closer this index is to 1.0, the closer the particle is to a perfect sphere. To measure Wardell sphericity (hereinafter also simply referred to as sphericity), for example, SEM (Scanning Electron Microscope) photographs can be used. Specifically, for example, approximately 100 primary particles are observed using SEM photographs, and their sphericities are calculated. The average value obtained by dividing the total calculated sphericities by the number of observed primary particles is taken as the sphericity.

[0150] When the Wardell sphericity is within the above-mentioned preferred range, resistance to hydrogen peroxide plasma sterilization is further improved, which is preferable, and when acoustic waves are irradiated onto the acoustic lens layer, the area of ​​the acoustic waves that strike the surface-treated oxide particles is reduced, which is thought to improve acoustic wave sensitivity. Note that, in this specification, "true spherical" also includes slightly distorted spheres with a Wardell sphericity in the range of 0.9 to 1, and the above-mentioned surface-treated spherical silica particles refer to surface-treated silica particles that are true spherical.

[0151] Among oxide particles, silica particles are roughly classified according to their manufacturing method into combustion silica (i.e., fumed silica) obtained by burning silane compounds, deflagration silica obtained by explosively burning metal silicon powder, wet silica obtained by the neutralization reaction of sodium silicate and mineral acid (among which, those synthesized under alkaline conditions are called precipitation silica, and those synthesized under acidic conditions are called gel silica), and sol-gel silica obtained by hydrolysis of hydrocarbyloxysilane (so-called Stoeber method).As the manufacturing method of spherical silica particles, explosion method and sol-gel method can be mentioned, and are preferred.

[0152] The sol-gel method is a method for producing a silane-based composite material essentially containing SiO by hydrolyzing and condensing a hydrocarbyloxysilane (preferably tetrahydrocarbyloxysilane) or a partial hydrolysis and condensation product thereof, or a combination thereof. ２ The hydrophobic treatment of the silica particle surface is a method for obtaining hydrophilic spherical silica particles consisting of R units. ３ ３ SiO １／２ Unit (R ３ are the same or different and represent a substituted or unsubstituted monovalent hydrocarbon group having 1 to 20 carbon atoms.) can be introduced. Specifically, this can be carried out by the methods described in JP-A-2007-99582 and JP-A-2014-114175, for example. Other surface treatments of oxide particles are also not particularly limited and can be carried out by ordinary methods.

[0153] (Other Components) In addition to the polyorganosiloxane (A) having a vinyl group, the polyorganosiloxane (B) having two or more Si—H groups in the molecular chain, and the surface-treated oxide particles, the silicone composition may appropriately contain at least one of a cure retarder, a solvent, a dispersant, a pigment, a dye, an antistatic agent, an antioxidant, a flame retardant, and a thermal conductivity improver.

[0154] - Cure Retarder - In the present invention, a cure retarder for the curing reaction can be used as appropriate. The cure retarder is used to slow down the addition curing reaction, and an example of such a cure retarder is a low molecular weight vinylmethylsiloxane homopolymer (trade name: VMS-005, manufactured by Gelest). The cure rate, i.e., working time, can be adjusted by adjusting the content of the cure retarder.

[0155] - Catalyst - In the present invention, a catalyst is used to obtain a layer by curing the silicone composition. Examples of catalysts include platinum or platinum-containing compounds (hereinafter simply referred to as platinum compounds). Platinum or platinum compounds used in room temperature curing (RTV) can be used without any particular restrictions, and platinum-vinyldisiloxane, for example, can be used. Specific examples include platinum black or platinum supported on an inorganic compound or carbon black, chloroplatinic acid or an alcohol solution of chloroplatinic acid, a complex salt of chloroplatinic acid and an olefin, and a complex salt of chloroplatinic acid and a vinylsiloxane. A single catalyst may be used alone, or two or more may be used in combination.

[0156] The catalyst is necessary for the hydrosilylation reaction in which the Si-H groups of the polyorganosiloxane (B) are added to the vinyl groups of the polyorganosiloxane (A). As the hydrosilylation reaction (addition curing reaction) progresses, the polyorganosiloxane (A) is crosslinked with the polyorganosiloxane (B), forming a silicone resin. Here, the catalyst may be mixed into the silicone composition, or may be brought into contact with the silicone composition without being contained in the silicone composition. The latter is preferred.

[0157] Examples of commercially available platinum catalysts include platinum compounds (trade name: PLATINUM CYCLOVINYLMETHYLSILOXANE COMPLEX IN CYCLIC METHYLVINYLSILOXANES (SIP6832.2), Pt concentration 2 mass%, and trade name: PLATINUM DIVINYLTETRAMETHYLDISILOXANE COMPLEX IN VINYL-TERMINATED POLYDIMETHYLSILOXANE (SIP6830.3), Pt concentration 3 mass%, both manufactured by Gelest).

[0158] The content of the catalyst to be reacted with the silicone composition is not particularly limited, but from the viewpoint of reactivity, it is preferably from 0.00001 to 0.05 parts by mass, more preferably from 0.00001 to 0.01 parts by mass, even more preferably from 0.00002 to 0.01 parts by mass, and particularly preferably from 0.00005 to 0.005 parts by mass, relative to 100 parts by mass of the silicone composition.

[0159] [Viscosity of silicone composition before curing] In order to uniformly disperse each component contained in the silicone composition, it is preferable that the viscosity of the silicone composition before the curing reaction is low. The viscosity before curing is measured by measuring the viscosity of the silicone composition before adding a catalyst that starts the curing reaction. Specifically, it can be measured by the method described in WO 2017 / 130890.

[0160] The viscosity (23°C) is preferably 5000 Pa·s or less, more preferably 1000 Pa·s or less, and even more preferably 200 Pa·s or less. The practical lower limit is 10 Pa·s or more.

[0161] In the acoustic wave probe of the present invention, another layer may be provided between the substrate and the intermediate layer. Any layer used in the acoustic wave probe can be used as the other layer, as long as it has excellent adhesion to the substrate and a reactive group that reacts (preferably forms a chemical bond) with the —OH group of the hydrolyzed silicate compound in the intermediate layer. For example, a polyimide layer, which is known to be provided between the acoustic matching layer and the acoustic lens in the acoustic wave probe to impart resistance to chemicals such as sterilization and disinfection, can be preferably used. Furthermore, the reactive group in the other layer that reacts (preferably forms a chemical bond) with the —OH group of the hydrolyzed silicate compound in the intermediate layer can be introduced by forming a layer that has excellent adhesion to the substrate and then subjecting the surface of this layer to chemical and / or physical treatment.

[0162] <Method of Manufacturing Acoustic Wave Probe> The acoustic wave probe of the present invention can be prepared by conventional methods. For example, the substrate, the liquid for forming the intermediate layer, and the room-temperature-curable silicone for forming the acoustic lens layer are each prepared by conventional methods. When the surface of the substrate on which the intermediate layer is to be formed is hydrophilized, the side on which the intermediate layer is to be formed is hydrophilized by conventional methods. The liquid for forming the intermediate layer is prepared by hydrolyzing a silicate compound having a hydrolyzable group to prepare a liquid containing a hydrolyzed silicate compound, or by adding and mixing a commercially available hydrolyzed silicate compound. When a liquid containing a hydrolyzed silicate compound is prepared by hydrolyzing a silicate compound having a hydrolyzable group, it is preferable to perform a neutralization treatment. Other components that may be contained in the liquid for forming the intermediate layer, such as a silane coupling agent, a titanium alkoxide compound, an aluminum alkoxide compound, or a zirconium alkoxide compound, may be added and mixed simultaneously with the preparation of these liquids, or may be added and mixed separately. In addition, when the silicone is prepared by hydrolyzing a silicate compound having a hydrolyzable group, it is preferable to add and mix the other components simultaneously after neutralization. The room-temperature-curable silicone for forming the acoustic lens layer can be obtained, for example, by kneading the components that make up the room-temperature-curable silicone using a kneader, pressure kneader, Banbury mixer (continuous kneader), or two-roll kneading device. The order in which the components are mixed is not particularly limited. The kneading conditions are not particularly limited, and it is preferable to knead, for example, at 10 to 50°C for 1 to 72 hours. After this kneading, it is preferable to contact the mixture with a catalyst immediately before use.

[0163] The acoustic wave probe of the present invention can be produced by applying a liquid for forming an intermediate layer to a substrate and drying it to form the intermediate layer, and then laminating and curing a room-temperature curable silicone for forming the acoustic lens layer on the intermediate layer, thereby producing an acoustic wave probe in which the substrate and the acoustic lens layer are bonded together. Note that the intermediate layer may be reacted separately from the acoustic lens layer, but it is preferable to proceed and complete the reaction simultaneously in the step of curing the room-temperature curable silicone to form the acoustic lens layer. Note that if the above-mentioned other layer is further provided between the substrate and the intermediate layer, the other layer may be formed before the step of forming the intermediate layer on the substrate.

[0164] The room-temperature curable silicone thus obtained can be cured to obtain a silicone resin that constitutes the acoustic lens layer. Specifically, the silicone resin can be obtained by, for example, heat curing at 20 to 50°C for 5 to 500 minutes. The shape of the silicone resin is not particularly limited; for example, it may be formed into a shape suitable for an acoustic lens using a mold during curing, or the silicone resin may be obtained in sheet form and then cut into the desired acoustic lens.

[0165] The acoustic wave probe of the present invention can be preferably used in an acoustic wave measurement device. The acoustic wave measurement device of the present invention is not limited to an ultrasound diagnostic device or a photoacoustic wave measurement device, but refers to a device that receives acoustic waves reflected or generated by an object and displays them as an image or signal intensity. In particular, the acoustic wave probe of the present invention can be preferably used as an ultrasound probe equipped with capacitive micromachined ultrasound transducers (cMUTs) as an ultrasound transducer array, and is also preferably used in an ultrasound diagnostic device equipped with this ultrasound probe. Specifically, the acoustic wave probe of the present invention is preferably applied to acoustic wave measurement devices such as the ultrasound diagnostic device described in JP 2003-169802 A and the photoacoustic wave measurement devices described in JP 2013-202050 A and JP 2013-188465 A.

[0166] The configuration of the acoustic wave probe of the present invention will be described in more detail below based on the configuration of an ultrasonic probe in an ultrasonic diagnostic apparatus shown in Fig. 1. Note that an ultrasonic probe is a probe that uses ultrasonic waves as the acoustic wave in the acoustic wave probe. Therefore, the basic structure of an ultrasonic probe can be applied directly to an acoustic wave probe.

[0167] - Ultrasonic Probe - The ultrasonic probe 10 is a main component of an ultrasonic diagnostic device, and has the function of generating ultrasonic waves and transmitting and receiving ultrasonic beams. As shown in Figure 1, the ultrasonic probe 10 is configured with an acoustic lens 1, an acoustic matching layer 2, a piezoelectric element layer 3, and a backing material 4, arranged in this order from the tip (the surface that comes into contact with the living body being examined). In recent years, a laminated structure has been proposed in which the transmitting ultrasonic vibrator (piezoelectric element) and the receiving ultrasonic vibrator (piezoelectric element) are made of different materials, with the aim of receiving higher harmonics.

[0168] <Piezoelectric Element Layer> The piezoelectric element layer 3 is a part that generates ultrasonic waves. Electrodes are attached to both sides of the piezoelectric element. When a voltage is applied, the piezoelectric element vibrates by repeatedly expanding and contracting, thereby generating ultrasonic waves.

[0169] The materials that make up the piezoelectric element include quartz crystal and LiNbO ３ , LiTaO ３ and KNbO ３ single crystals such as ZnO and AlN, thin films such as Pb(Zr,Ti)O ３Inorganic ceramic piezoelectric materials, which are obtained by polarization-treating sintered bodies such as those based on the PZT system, are widely used. Generally, piezoelectric ceramics such as PZT (lead zirconate titanate), which have good conversion efficiency, are used. Furthermore, piezoelectric elements that detect high-frequency received waves require sensitivity over a wider bandwidth. For this reason, organic piezoelectric materials using organic polymeric materials such as polyvinylidene fluoride (PVDF) are used as piezoelectric elements suitable for high frequencies and wide bandwidths. Furthermore, Japanese Patent Laid-Open Publication No. 2011-071842 and other publications describe cMUTs that utilize MEMS (Micro Electro Mechanical Systems) technology, exhibiting excellent short-pulse and wide-band characteristics, and enabling mass production with minimal characteristic variation, resulting in an array structure. Any of these piezoelectric element materials can be preferably used in the present invention.

[0170] <Backing Material> The backing material 4 is provided on the back surface of the piezoelectric element layer 3, and reduces the pulse width of the ultrasonic waves by suppressing excess vibrations, thereby contributing to improving the distance resolution in ultrasonic diagnostic images.

[0171] <Acoustic Matching Layer> The acoustic matching layer 2 is provided to reduce the difference in acoustic impedance between the piezoelectric element layer 3 and the object to be examined, and to efficiently transmit and receive ultrasonic waves.

[0172] <Acoustic Lens> The acoustic lens 1 is provided to utilize refraction to focus ultrasonic waves in the slice direction and improve resolution. It is also required to be in close contact with the living body being examined, and to match the ultrasonic waves to the acoustic impedance of the living body (1.4 to 1.7 Mrayl for the human body). In other words, the acoustic lens 1 is made of a material whose acoustic speed is sufficiently slower than that of the human body and whose acoustic impedance is close to that of human skin, thereby improving the ultrasonic transmission and reception sensitivity.

[0173] <Intermediate Layer> In one embodiment of the acoustic wave probe of the present invention, the substrate in the acoustic wave probe of the present invention corresponds to the acoustic matching layer 2, and the above-mentioned acoustic lens layer in the acoustic wave probe of the present invention corresponds to the acoustic lens 1, and the acoustic matching layer 2 and the acoustic lens 1 are bonded together by an intermediate layer (not shown in FIG. 1 ) containing the specific siloxane compound described above. Note that the substrate in the acoustic wave probe of the present invention is also preferably a component other than the acoustic matching layer 2 around the acoustic lens 1, in addition to the acoustic matching layer 2. In this case, the acoustic matching layer 2 and the component other than the acoustic matching layer 2 around the acoustic lens 1 are bonded to the acoustic lens 1 by an intermediate layer containing the specific siloxane compound described above.

[0174] The operation of the ultrasonic probe 10 configured as described above will now be described. A voltage is applied to the electrodes provided on both sides of the piezoelectric element layer 3 to resonate the piezoelectric element layer 3, and an ultrasonic signal is transmitted to the subject through the acoustic lens 1. During reception, the piezoelectric element layer 3 is vibrated by a reflected signal (echo signal) from the subject, and this vibration is electrically converted into a signal to obtain an image.

[0175] In particular, the acoustic lens layer in the acoustic wave probe of the present invention can be confirmed to have a significant sensitivity improvement effect at ultrasonic transmission frequencies of approximately 10 MHz or higher, as compared to a typical medical ultrasonic transducer. Particularly significant sensitivity improvement effects can be expected at ultrasonic transmission frequencies of 15 MHz or higher. The acoustic lens layer in the acoustic wave probe of the present invention can, for example, reduce the speed of sound to less than 900 m / s, and can obtain sufficiently accurate information about biological tissue at a depth of 0.1 to 20 mm from the body surface at ultrasonic frequencies of 10 MHz or higher but lower than 50 MHz. Devices in which the acoustic lens layer in the acoustic wave probe of the present invention particularly functions to address conventional problems are described in detail below. It should be noted that the acoustic wave probe of the present invention also exhibits excellent effects in devices other than those described below.

[0176] - Ultrasonic probe equipped with a cMUT (capacitive micromachined ultrasonic transducer) - When a cMUT device, such as those described in Japanese Patent Application Laid-Open No. 2006-157320 or Japanese Patent Application Laid-Open No. 2011-71842, is used in an ultrasonic transducer array, its sensitivity is generally lower than that of a transducer using a typical piezoelectric ceramic (PZT). However, as described in International Publication No. 2017 / 130890, the acoustic lens layer used in the acoustic wave probe of the present invention can be made up for by using an acoustic lens obtained from a specific acoustic wave probe composition. This allows the sensitivity of the cMUT to approach the performance of conventional transducers. Furthermore, because the cMUT device is fabricated using MEMS technology, it is more mass-producible than piezoelectric ceramic probes, making it possible to provide ultrasonic probes at a lower cost to the market.

[0177] Photoacoustic wave measurement device using photoacoustic wave imaging Photoacoustic wave imaging (PAI), as described in JP 2013-158435 A and other publications, irradiates the inside of the human body with light (electromagnetic waves) and displays an image of ultrasound waves generated when the irradiated light causes adiabatic expansion of human tissue, or the signal intensity of the ultrasound waves.

[0178] Ultrasonic endoscopes, such as those described in Japanese Patent Laid-Open No. 2008-311700, have a signal line cable that is longer than the body surface transducer due to its structure, and cable loss makes it difficult to improve the sensitivity of the transducer. Furthermore, it is said that there is no effective means of improving sensitivity to address this issue for the following reasons.

[0179] First, in the case of an ultrasound diagnostic device for use on the body surface, it is possible to install an amplifier circuit, an AD conversion IC (analog-to-digital conversion integrated circuit), etc. at the tip of the transducer. In contrast, because an ultrasound endoscope is inserted into the body for use, the installation space for the transducer is narrow, making it difficult to install an amplifier circuit, an AD conversion IC, etc. at the tip of the transducer. Second, due to their physical properties and process suitability, piezoelectric single crystals used in transducers in ultrasound diagnostic devices for use on the body surface are difficult to apply to transducers with ultrasound transmission frequencies of 10 to 15 MHz or higher. However, because the ultrasound probes in ultrasound endoscopes generally have ultrasound transmission frequencies of 10 to 15 MHz or higher, it is also difficult to improve sensitivity using piezoelectric single crystal materials.

[0180] However, by using an acoustic lens obtained from a specific composition for acoustic probes as the acoustic lens layer used in the acoustic wave probe of the present invention, as described in WO 2017 / 130890, it is possible to improve the sensitivity of the endoscopic ultrasonic transducer. Furthermore, even when the same ultrasonic transmission frequency (e.g., 15 MHz) is used, particularly effectiveness is demonstrated when an acoustic lens obtained from a specific composition for acoustic probes as described in WO 2017 / 130890 is used as the acoustic lens layer used in the acoustic wave probe of the present invention in the endoscopic ultrasonic transducer.

[0181] The present invention will be described in more detail below with reference to examples. The present invention is not to be construed as being limited to the examples shown below except as defined in the present invention.

[0182] <1. Substrate (B)> Test pieces measuring 80 mm in length x 20 mm in width x 1 mm in thickness were cut out from various substrates (B-1) to (B-14) listed in the notes of the table below. One side of each of these substrate test pieces was treated with a "UVO-Cleaner Model 42" (trade name, manufactured by Jlight, central wavelength 254 nm) for 2 minutes to prepare UV1-pretreated substrates (B-1) to (B-14). One side of the substrate (B-4) test piece was treated with a Xe excimer UV irradiation device "ASM86 Excimer" (trade name, manufactured by Asumi Giken Co., Ltd., central wavelength 172 nm) to prepare a UV2-pretreated substrate (B-4). One side of a test piece of the substrate (B-4) was treated with a plasma treatment device "PM100" (trade name, manufactured by Yamato Scientific Co., Ltd.) to prepare a plasma pretreated substrate (B-4). One side of a test piece of the substrate (B-4) was treated with a corona discharge surface modification device "Corona Master PS-1M" (trade name, manufactured by Shinko Electric Instrumentation Co., Ltd.) to prepare a corona pretreated substrate (B-4).

[0183] <2. Preparation of Intermediate Layer Liquid> (1) Preparation of Intermediate Layer Liquid (m-1) 2.4 g of hydrolyzed silicate "HAS-1" (trade name, manufactured by Nippon Colcoat Co., Ltd., silica content 21%) and 7.6 g of methanol were mixed to obtain intermediate layer liquid (m-1). (2) Formation of Intermediate Layer Liquid (m-2) 2.4 g of hydrolyzed silicate "HAS-1" (trade name, manufactured by Nippon Colcoat Co., Ltd., silica content 21%), 0.3 g of N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane (trade name: KBM-603, manufactured by Shin-Etsu Chemical Co., Ltd.), and 7.3 g of methanol were mixed to obtain intermediate layer liquid (m-2). (3) Formation of Intermediate Layer Solutions (m-3) to (m-25) Intermediate layer solutions (m-3) to (m-25) were prepared in the same manner as in the above (m-1) and (m-2), by mixing the components shown in Table A below. Note that intermediate layer solutions (m-18) to (m-20) were prepared by mixing and stirring the components shown in Table A until the hydrolysis of the hydrolyzable groups in the silicate compounds progressed and the aforementioned hydrolysis rate reached 80% or more, and then neutralizing the solutions with 0.02 N aqueous ammonia to a pH of 5 to 7.

[0184]

[0185] (Notes for the table) [Compounds used in preparing the intermediate layer liquid] In the following explanation, silica content means the mass ratio of the hydrolyzed silicate compound or silicate compound having a hydrolyzable group in the product. The content of each component listed in the table is on a mass basis. (Hydrolyzed silicate compound) HAS-1: Trade name, manufactured by Nippon Colcoat Co., Ltd., silica content 21%, weight average molecular weight 650 (Silicate compound having a hydrolyzable group) Methyl silicate 51: Trade name, manufactured by Nippon Colcoat Co., Ltd., Si ４ O ３ (OCH ３ ) １０ (average tetramer), silica content 51%, weight average molecular weight 470 MKC Silicate MS56: trade name, manufactured by Mitsubishi Chemical Corporation, Si ｍ O ｍ－１ (OCH ３ ) ２ｍ＋２ (m = 2 to 100), silica content 56%, weight average molecular weight 1,150 TEOS: tetraethoxysilane

[0186] (Silane Coupling Agents) (SI-1): N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane (trade name: KBM-603, manufactured by Shin-Etsu Chemical Co., Ltd.) (SI-2): 3-aminopropyltrimethoxysilane (trade name: KBM-903, manufactured by Shin-Etsu Chemical Co., Ltd.) (SI-3): 3-trimethoxysilylpropylsuccinic anhydride (trade name: X-12-967C, manufactured by Shin-Etsu Chemical Co., Ltd.) (SI-4): 3-glycidoxypropyltrimethoxysilane (trade name: KBM-403, manufactured by Shin-Etsu Chemical Co., Ltd.)

[0187] (Titanium Alkoxide Compounds) (TI-1): Isopropyl tri(N-aminoethyl-aminoethyl) titanate (trade name: PLENACT 44, manufactured by Ajinomoto Fine-Techno Co., Ltd.) (TI-2): Diisopropyl bis(dioctyl pyrophosphate) titanate (trade name: PLENACT 38S, manufactured by Ajinomoto Fine-Techno Co., Ltd.) (TI-3): Isopropyl tridodecylbenzenesulfonyl titanate (trade name: PLENACT 9SA, manufactured by Ajinomoto Fine-Techno Co., Ltd.) (TI-4): Tetra n-butyl titanate (trade name: ORGATIX TA-21, manufactured by Matsumoto Fine Chemical Co., Ltd.)

[0188] (Aluminum Alkoxide Compounds) (AL-1): Aluminum trisacetylacetonate (trade name: Orgatix AL-3100, manufactured by Matsumoto Fine Chemical Co., Ltd.) (AL-2): Aluminum bisethylacetoacetate monoacetylacetonate (trade name: Orgatix AL-3200, manufactured by Matsumoto Fine Chemical Co., Ltd.) (AL-3): Aluminum trisethylacetoacetate (trade name: Orgatix AL-3215, manufactured by Matsumoto Fine Chemical Co., Ltd.) (AL-4): Aluminum sec-butoxide (trade name: ASBD, manufactured by Kawaken Fine Chemical Co., Ltd.)

[0189] (Zirconium Alkoxide Compounds) (ZR-1): Zirconium tetraacetylacetonate (trade name: Orgatix ZC-150, manufactured by Matsumoto Fine Chemical Co., Ltd.) (ZR-2): Zirconium lactate ammonium salt (trade name: Orgatix ZC-300, manufactured by Matsumoto Fine Chemical Co., Ltd.) (ZR-3): Zirconium tri-n-butoxymonoacetylacetonate (trade name: Orgatix ZC-540, manufactured by Matsumoto Fine Chemical Co., Ltd.) (ZR-4): Zirconium tetra-n-butoxide (trade name: Orgatix ZA-65, manufactured by Matsumoto Fine Chemical Co., Ltd.)

[0190] 3. Preparation of Resin for Acoustic Lenses (1) Preparation of Resin (L-1) for Acoustic Lenses 54.0 parts by mass of vinyl-terminated diphenylsiloxane-dimethylsiloxane copolymer ("PDV-0535" manufactured by Gelest, mass average molecular weight 47,500, diphenylsiloxane amount 5 mol%), 1.0 part by mass of polymethylhydrosiloxane ("HMS-991" manufactured by Gelest, mass average molecular weight 1,600), and 45.0 parts by mass of spherical surface-treated silica ("QSG-30" manufactured by Shin-Etsu Chemical Co., Ltd., average primary particle diameter 30 nm, methyltrimethoxysilane and hexamethyldisilazane (HMDS) surface-treated product, methanol hydrophobicity degree 67% by mass) were kneaded in a kneader for 2 hours at a set temperature of 23°C to form a uniform paste. To this was added 0.05 parts by mass of a platinum catalyst solution (manufactured by Gelest, trade name "SIP6830.3", Pt concentration 3% by mass), and after mixing, the mixture was degassed under reduced pressure to prepare uncured acoustic lens resin (L-1). (2) Preparation of acoustic lens resin (L-2) Uncured acoustic lens resin (L-2) was prepared in the same manner as in the preparation of acoustic lens resin (L-1), except that the vinyl-terminated diphenylsiloxane-dimethylsiloxane copolymer was changed to 54.0 parts by mass of "PDV-0341" (manufactured by Gelest, mass average molecular weight 62,000, diphenylsiloxane amount 3 mol%). (3) Preparation of Resin for Acoustic Lenses (L-3) Uncured Resin for Acoustic Lenses (L-3) was prepared in the same manner as in the preparation of Resin for Acoustic Lenses (L-1), except that the silica was replaced with 45.0 parts by mass of surface-treated titanium oxide "TITONE R-24" (trade name, manufactured by Sakai Chemical Industry Co., Ltd., average primary particle size 0.20 μm, surface treatment agent: silica-alumina-organic). (4) Preparation of Resin for Acoustic Lenses (L-4) Uncured Resin for Acoustic Lenses (L-4) was prepared in the same manner as in the preparation of Resin for Acoustic Lenses (L-1), except that the silica was replaced with 45.0 parts by mass of non-spherical surface-treated fumed silica ("Aerosil (registered trademark) NAX50" manufactured by Nippon Aerosil Co., Ltd., average primary particle size 30 nm, hexamethyldisilazane (HMDS) surface-treated product, methanol hydrophobicity degree 28% by mass).(5) Preparation of Resin (L-5) for Acoustic Lenses The same process was carried out as in the preparation of Resin (L-1) for acoustic lenses, except that the vinyl-terminated diphenylsiloxane-dimethylsiloxane copolymer was changed to 54.0 parts by mass of vinyl-terminated dimethylsiloxane copolymer “DMS-V41” (manufactured by Gelest Corporation, mass average molecular weight 62,700, diphenylsiloxane amount 0 mol%), to prepare uncured Resin (L-5) for acoustic lenses.

[0191] <4. Preparation of Laminate> The intermediate layer liquid (m-1) was applied to the entire treated surface of the UV1-pretreated substrate (B-1) using a cotton swab, and the substrate was dried at 50°C for 15 minutes to form an intermediate layer (M-1). The substrate with this intermediate layer attached was set in a mold, and acoustic lens resin (L-1) that had been degassed and mixed in advance was poured onto the treated surface. The lens resin was placed so that the thickness was 1 mm (total thickness of the laminate was approximately 2 mm), and then cured at 100°C for 10 minutes to obtain Laminate No. 101, in which the acoustic lens layer (L) was attached to the substrate (B) via the intermediate layer (M). Laminates Nos. 102 to 140 and c01 to c07 were prepared in the same manner as in the preparation of Laminate No. 101, except that the substrate (B), intermediate layer (M), and acoustic lens layer (L) were changed to the compositions described in Tables 1-1 and 1-2 below. Laminate Nos. Laminates Nos. 101 to 140 are acoustic wave probes of the present invention, and laminates Nos. c01 to c07 are acoustic wave probes for comparison.

[0192] The average layer thickness of the intermediate layer (M) was calculated as follows. The laminate prepared above was cut at five random locations, and the cross section of each intermediate layer (M) was observed at 50,000x magnification using a scanning electron microscope (S-5500 (product name), manufactured by Hitachi High-Technologies Corporation), and the thickness of the intermediate layer (M) was obtained at one point on each cross section. The average value of the five thickness values ​​obtained was taken as the average layer thickness. This is shown in the film thickness column in the tables below.

[0193] <5. Evaluation of Laminate> The laminates prepared above were evaluated for peel strength, heat cycle durability, and hydrogen peroxide plasma sterilization resistance as follows. The obtained results are summarized in Tables 1-1 and 1-2 below. Note that the hydrogen peroxide plasma sterilization resistance is indicated by H ２ O ２This is referred to as gas sterilization durability.

[0194] Test Example 1: Evaluation of Peel Strength A test piece measuring 80 mm in length and 10 mm in width (approximately 2 mm thick) was cut from the laminate prepared above to obtain a laminate test piece. A 1 cm-wide slit was made in the middle layer on the 10 mm-wide side of this laminate test piece. The 90° peel strength between the substrate (B) and the acoustic lens layer (L) of this slit-made laminate test piece was measured at 25°C by gripping the end of the 1 cm-wide slit on the acoustic lens layer side and peeling 20 mm along the longitudinal direction at a peel rate of 2 mm / min while maintaining a 90° angle between the substrate and the acoustic lens layer. The peel strength was measured using a force gauge and expressed in N / cm. The average value of the measured peel strength over the entire region was evaluated according to the following criteria. <Peel Strength Evaluation Criteria> AA: 12 N / cm or more, or cohesive failure of the resin constituting the acoustic lens layer occurred. A: 10 N / cm or more and less than 12 N / cm B: 6 N / cm or more and less than 10 N / cm C: 2 N / cm or more and less than 6 N / cm D: Less than 2 N / cm Note that with a peel strength of less than 12 N / cm, cohesive failure of the resin that makes up the acoustic lens layer does not occur.

[0195] Test Example 2 Evaluation of Heat Cycle Durability The laminated test specimens prepared in Test Example 1 above were subjected to 500 cycles of heat cycle testing, with one cycle consisting of 2 hours at -20°C and 2 hours at 60°C, using a thermo-hygrostat (KHWV-40HP (trade name), manufactured by Satake Chemical Machinery Co., Ltd.). After 500 cycles of the heat cycle test, the 90° peel strength of the laminated test specimens was measured by the method described in Test Example 1 above. The 90° peel strength measured in Test Example 1 above before the heat cycle treatment was designated "PSB(1)" and the 90° peel strength measured after the heat cycle treatment was designated "PSA(1)". The ratio of "PSA(1)" to "PSB(1)" {(PSA(1) / PSB(1)) x 100(%)} was calculated and evaluated according to the following criteria. <Evaluation criteria for heat cycle resistance> AA: 80% or more A: 60% or more and less than 80% B: 40% or more and less than 60% C: 20% or more and less than 40% D: Less than 20%

[0196] Test Example 3 Evaluation of Hydrogen Peroxide Plasma Sterilization Resistance The laminated test piece prepared in Test Example 1 above was subjected to 50 repeated low-temperature plasma sterilization treatments using the advanced course of a hydrogen peroxide gas sterilizer ("Sterrad (registered trademark) NX" manufactured by ASP). After 50 hydrogen peroxide plasma sterilization tests, the laminated test piece was measured for 90° peel strength using the method described in Test Example 1 above. The laminated test piece was placed on a stainless steel plate, through which hydrogen peroxide gas and the more powerful decomposition and activation products of hydrogen peroxide gas generated by irradiating it with plasma hardly penetrate, with the acoustic lens layer (L) on the upper side and the substrate (B) on the lower side, and then subjected to the hydrogen peroxide plasma sterilization treatment. The 90° peel strength measured in Test Example 1 before the hydrogen peroxide plasma sterilization treatment was designated "PSB(2)", and the 90° peel strength measured after the hydrogen peroxide plasma sterilization test was designated "PSA(2)". The ratio of "PSA(2)" to "PSB(2)" {(PSA(2) / PSB(2)) x 100(%)} was calculated and evaluated according to the following criteria. <Criteria for evaluating hydrogen peroxide plasma sterilization resistance> AA: 80% or more A: 60% or more but less than 80% B: 40% or more but less than 60% C: 20% or more but less than 40% D: Less than 20%

[0197]

[0198]

[0199] [Substrate (B)] (Materials) (B-1): Acrylic resin (trade name: Acrylite L, manufactured by Mitsubishi Chemical Corporation) (B-2): PC (polycarbonate) resin (trade name: Panlite L-1225Y, manufactured by Teijin Limited) (B-3): GPPS (general-purpose polystyrene) resin (trade name: PSJ-Polystyrene HF77, manufactured by PS Japan Co., Ltd.) (B-4): Cross-linked PS (cross-linked polystyrene) resin (trade name: Rexolite, manufactured by Ensinger) (B-5): Epoxy resin (trade name: Two-component epoxy resin adhesive 6100, manufactured by Alteco Co., Ltd.) cured at 25°C for 24 hours. (B-6): Phenolic resin (trade name: Sumicon PM-760, manufactured by Sumitomo Bakelite Co., Ltd.) heat-cured at 180°C for 30 minutes. (B-7): Non-PEs (unsaturated polyester) resin (product name: U-Pica 4072, manufactured by Japan U-Pica Corporation) heat-cured at 100°C for 24 hours. (B-8): PI (polyimide) resin (thermosetting polyimide resin, product name: Kapton, manufactured by Toray DuPont Co., Ltd.). (B-9): Melamine resin (product name: MULAS MBF-C, manufactured by Panasonic Corporation) heat-cured at 150°C for 10 minutes. (B-10): Glass. (B-11): Ceramics. (B-12): Graphite. (B-13): Al (aluminum). (B-14): Cu (copper). (Pretreatment) UV1, UV2, Plasma, Corona: These represent the aforementioned UV1 pretreatment, UV2 pretreatment, plasma pretreatment, and corona pretreatment, respectively. "-" indicates that no pretreatment was performed.

[0200] [Intermediate Layer (M)] Intermediate layers (M-1) to (M-25): Prepared using the intermediate layer solutions (m-1) to (m-25) described above, respectively.

[0201] [Acoustic Lens Layer (L)] Acoustic lens layers (L-1) to (L-5): Produced using the above-described acoustic lens resins (L-1) to (L-5), respectively.

[0202] The following can be seen from Tables 1-1 and 1-2. Comparative laminate No. c01 does not meet the requirements of the present invention in that the substrate and the acoustic lens layer defined in the present invention are directly bonded together without an intermediate layer. This comparative laminate No. c01 had low initial peel strength, poor initial adhesion, and poor resistance to hydrogen peroxide plasma sterilization. Comparative laminates Nos. c02 to c06 do not meet the requirements of the present invention in that, although an intermediate layer is interposed between the substrate and the acoustic lens layer defined in the present invention, the intermediate layer does not contain a siloxane compound derived from a hydrolyzed silicate compound. All of these comparative laminates Nos. c02 to c06 had poor resistance to hydrogen peroxide plasma sterilization. Comparative laminate No. c07 does not meet the requirements of the present invention in that, although an intermediate layer defined in the present invention is interposed between the substrate and the acoustic lens layer, the acoustic lens layer is a layer formed by curing a room-temperature-curable silicone that does not contain a structural unit having a phenyl group. This comparative laminate No. c07 was poor in resistance to hydrogen peroxide plasma sterilization. In contrast, laminates Nos. 101 to 140, which are defined in the present invention and comprise a substrate, an intermediate layer, and an acoustic lens layer laminated in this order, all had high initial peel strength and maintained 20% or more of the initial peel strength after hydrogen peroxide plasma sterilization, demonstrating excellent initial adhesion and resistance to hydrogen peroxide plasma sterilization.

[0203] While the present invention has been described in connection with embodiments thereof, we do not intend to limit our invention to any of the details of the description unless otherwise specified, and believe that the claims should be construed broadly without departing from the spirit and scope of the invention as set forth in the appended claims.

[0204] This application claims priority based on Japanese Patent Application No. 2022-104704, filed in Japan on June 29, 2022, the contents of which are incorporated herein by reference.

[0205] REFERENCE SIGNS LIST 1 acoustic lens 2 acoustic matching layer 3 piezoelectric element layer 4 backing material 7 housing 9 cord 10 ultrasonic probe

Claims

1. A substrate, an intermediate layer on the substrate, and an acoustic lens layer on the intermediate layer, the intermediate layer is a layer containing a siloxane compound, the siloxane compound having a constituent component derived from a hydrolyzed silicate compound, An acoustic wave probe, wherein the acoustic lens layer is a layer formed by curing a room temperature curable silicone, and the room temperature curable silicone includes a structural unit having a phenyl group.

2. The acoustic wave probe of claim 1 , wherein the substrate comprises at least one of ferrous, non-ferrous metals, inorganic materials other than metals, and organic materials.

3. 3. The acoustic wave probe of claim 2, wherein the non-ferrous metal comprises at least one of aluminum, titanium, magnesium, nickel, copper, lead, zinc, tin, chromium, tungsten, or cobalt, or an alloy of at least two of these metals.

4. 4. The acoustic wave probe according to claim 2, wherein the non-metallic inorganic material includes at least one of glass, ceramics, and graphite.

5. The acoustic wave probe of claim 2 , wherein the organic material comprises at least one of a thermoplastic resin and a thermosetting resin.

6. The acoustic wave probe of claim 5 , wherein the thermoplastic resin comprises at least one of an acrylic resin, a polycarbonate resin, a styrene-based resin, and a polyphenylene sulfide resin.

7. 7. The acoustic wave probe according to claim 5, wherein the thermoplastic resin is a crosslinked thermoplastic resin.

8. The acoustic wave probe according to claim 1 , wherein the substrate is a substrate having a surface on the side of the intermediate layer that has been subjected to a hydrophilization treatment.

9. The acoustic wave probe according to claim 8 , wherein the substrate is a substrate having a surface on the intermediate layer side that has been subjected to at least one of ultraviolet treatment, ozone treatment, plasma treatment, and corona treatment.

10. The acoustic wave probe of claim 1 , wherein the intermediate layer comprises a component derived from at least one of a silane coupling agent, a titanium alkoxide compound, an aluminum alkoxide compound, and a zirconium alkoxide compound.

11. The acoustic wave probe of claim 1 , wherein the room temperature curable silicone is a silicone composition comprising a vinyl silicone and a hydrosilicone.

12. The acoustic wave probe of claim 11 , wherein the silicone composition comprises surface treated oxide particles.

13. The acoustic wave probe of claim 12 , wherein the silicone composition comprises surface-treated spherical silica particles.

14. The acoustic wave probe according to any one of claims 1 to 3, 5, 6, or 8 to 13, wherein the acoustic wave probe is an ultrasonic probe.

15. An acoustic wave measuring device comprising the acoustic wave probe according to any one of claims 1 to 3, 5, 6, or 8 to 13.

16. An ultrasonic diagnostic device comprising the acoustic wave probe according to claim 14.