WO2023067899A1 - 透明導電圧電フィルム、デバイス、および透明導電圧電フィルムの製造方法 - Google Patents

透明導電圧電フィルム、デバイス、および透明導電圧電フィルムの製造方法 Download PDF

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WO2023067899A1
WO2023067899A1 PCT/JP2022/032536 JP2022032536W WO2023067899A1 WO 2023067899 A1 WO2023067899 A1 WO 2023067899A1 JP 2022032536 W JP2022032536 W JP 2022032536W WO 2023067899 A1 WO2023067899 A1 WO 2023067899A1
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transparent
piezoelectric film
coating layer
less
transparent conductive
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English (en)
French (fr)
Japanese (ja)
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誠 今治
慧 山口
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Kureha Corp
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Kureha Corp
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Priority to US18/702,026 priority Critical patent/US20240415022A1/en
Priority to CN202280063215.0A priority patent/CN117999869A/zh
Priority to EP22883211.9A priority patent/EP4422380B1/en
Priority to KR1020247012555A priority patent/KR102814226B1/ko
Priority to JP2023554970A priority patent/JP7624084B2/ja
Publication of WO2023067899A1 publication Critical patent/WO2023067899A1/ja
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    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N30/00—Piezoelectric or electrostrictive devices
    • H10N30/80—Constructional details
    • H10N30/85—Piezoelectric or electrostrictive active materials
    • H10N30/857—Macromolecular compositions
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N30/00—Piezoelectric or electrostrictive devices
    • H10N30/50—Piezoelectric or electrostrictive devices having a stacked or multilayer structure
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B27/00—Layered products comprising a layer of synthetic resin
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B7/00—Layered products characterised by the relation between layers; Layered products characterised by the relative orientation of features between layers, or by the relative values of a measurable parameter between layers, i.e. products comprising layers having different physical, chemical or physicochemical properties; Layered products characterised by the interconnection of layers
    • B32B7/02—Physical, chemical or physicochemical properties
    • B32B7/023—Optical properties
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B7/00—Layered products characterised by the relation between layers; Layered products characterised by the relative orientation of features between layers, or by the relative values of a measurable parameter between layers, i.e. products comprising layers having different physical, chemical or physicochemical properties; Layered products characterised by the interconnection of layers
    • B32B7/02—Physical, chemical or physicochemical properties
    • B32B7/025—Electric or magnetic properties
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J7/00—Chemical treatment or coating of shaped articles made of macromolecular substances
    • C08J7/04—Coating
    • C08J7/042—Coating with two or more layers, where at least one layer of a composition contains a polymer binder
    • C08J7/0423—Coating with two or more layers, where at least one layer of a composition contains a polymer binder with at least one layer of inorganic material and at least one layer of a composition containing a polymer binder
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J7/00—Chemical treatment or coating of shaped articles made of macromolecular substances
    • C08J7/04—Coating
    • C08J7/044—Forming conductive coatings; Forming coatings having anti-static properties
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N30/00—Piezoelectric or electrostrictive devices
    • H10N30/01—Manufacture or treatment
    • H10N30/04—Treatments to modify a piezoelectric or electrostrictive property, e.g. polarisation characteristics, vibration characteristics or mode tuning
    • H10N30/045—Treatments to modify a piezoelectric or electrostrictive property, e.g. polarisation characteristics, vibration characteristics or mode tuning by polarising
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N30/00—Piezoelectric or electrostrictive devices
    • H10N30/01—Manufacture or treatment
    • H10N30/06—Forming electrodes or interconnections, e.g. leads or terminals
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N30/00—Piezoelectric or electrostrictive devices
    • H10N30/01—Manufacture or treatment
    • H10N30/09—Forming piezoelectric or electrostrictive materials
    • H10N30/098—Forming organic materials
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N30/00—Piezoelectric or electrostrictive devices
    • H10N30/80—Constructional details
    • H10N30/87—Electrodes or interconnections, e.g. leads or terminals
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N30/00—Piezoelectric or electrostrictive devices
    • H10N30/80—Constructional details
    • H10N30/87—Electrodes or interconnections, e.g. leads or terminals
    • H10N30/877—Conductive materials
    • H10N30/878—Conductive materials the principal material being non-metallic, e.g. oxide or carbon based
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N30/00—Piezoelectric or electrostrictive devices
    • H10N30/80—Constructional details
    • H10N30/88—Mounts; Supports; Enclosures; Casings
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2327/00—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Derivatives of such polymers
    • C08J2327/02—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Derivatives of such polymers not modified by chemical after-treatment
    • C08J2327/12—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Derivatives of such polymers not modified by chemical after-treatment containing fluorine atoms
    • C08J2327/16—Homopolymers or copolymers of vinylidene fluoride
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2433/00—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Derivatives of such polymers
    • C08J2433/02—Homopolymers or copolymers of acids; Metal or ammonium salts thereof

Definitions

  • the present invention relates to a transparent conductive piezoelectric film, a device, and a method for manufacturing a transparent conductive piezoelectric film.
  • a piezoelectric material is a material that generates a proportional voltage when pressure is applied, and conversely deforms when a voltage is applied, that is, a material that has a piezoelectric effect.
  • Piezoelectric materials are used for actuators, sensors, oscillator circuits or filter circuits in analog circuits, and the like, due to their piezoelectric effect.
  • transparent piezoelectric materials are useful, and highly transparent piezoelectric materials are particularly desired depending on the application.
  • Patent Literature 1 discloses a technique for suppressing the occurrence of tint in a transparent conductive film using a transparent film substrate that does not have piezoelectric properties.
  • a conductive piezoelectric film obtained by manufacturing a piezoelectric film using a highly transparent piezoelectric material and then laminating a transparent electrode on the piezoelectric film does not sufficiently maintain its transparency.
  • An object of one aspect of the present invention is to realize a transparent conductive piezoelectric film having transparency.
  • a transparent conductive piezoelectric film according to an aspect of the present invention has a piezoelectric constant d31 of 10 pC/N or more and 40 pC/N or less, a total light transmittance of 90% or more, A transparent conductive piezoelectric film comprising a transparent electrode layer.
  • a first transparent coating layer and a second transparent coating are formed on at least one surface of the transparent piezoelectric film.
  • a method for producing a laminated film comprising a layer and a transparent electrode layer laminated in this order, wherein the transparent piezoelectric film forming a film having a refractive index of 1.30 or more and less than 1.45 is manufactured.
  • a transparent conductive piezoelectric film having transparency can be realized.
  • 1 is a transparent conductive piezoelectric film 11 according to one embodiment of the present invention
  • 1 is a transparent conductive piezoelectric film 12 according to one embodiment of the present invention
  • a transparent conductive piezoelectric film according to one embodiment of the present invention is a film in which a transparent electrode layer is provided on a piezoelectric film.
  • the transparent conductive piezoelectric film of this embodiment has a piezoelectric constant d31 of 10 pC/N or more and 40 pC/N or less, and a total light transmittance of 90% or more.
  • the transparent conductive piezoelectric film has excellent piezoelectric properties, transparency, and conductivity, and can be suitably used for a wide range of devices.
  • the piezoelectric constant d31 may be 10 pC/N or more, preferably 14 pC/N or more, more preferably 18 pC/N or more. In the transparent conductive piezoelectric film, the piezoelectric constant d31 may be 40 pC/N or less, may be 35 pC/N or less, or may be 30 pC/N or less. Such a piezoelectric constant is achieved by the piezoelectric film provided by the transparent conductive piezoelectric film.
  • the piezoelectric constant d 31 indicates the displacement of the film in the lateral direction (perpendicular to the direction of the electric field) with respect to the applied voltage. It is preferable that the piezoelectric constant d31 does not fall below the lower limit from the viewpoint of imparting sufficient piezoelectric properties to the transparent conductive piezoelectric film. The larger the piezoelectric constant d31 , the larger the amount of displacement with respect to the applied voltage, which is particularly preferable from the viewpoint of use as an actuator. On the other hand, the piezoelectric constant d31 is 40 pC/N or less from the viewpoint of feasibility with the transparent conductive piezoelectric film.
  • a transparent conductive piezoelectric film having such a piezoelectric constant d31 is expected to be applied to a wide range of devices. For example, it is expected to be applied to sensors such as pressure sensors and vibration sensors, switches, energy harvesting elements, actuators, touch panels, haptic devices, speakers, and microphones.
  • sensors such as pressure sensors and vibration sensors, switches, energy harvesting elements, actuators, touch panels, haptic devices, speakers, and microphones.
  • a transparent conductive piezoelectric film having a piezoelectric constant d31 within the above range is particularly suitable for actuator applications.
  • the transparent conductive piezoelectric film may have a total light transmittance of 90% or more, preferably 91% or more, and more preferably 92% or more. Since the total light transmittance is within this range, it can be suitably used for devices that require transparency. For example, when it is used for the display of any device, it is preferable to be transparent because it does not interfere with the display screen of the display.
  • the transparent conductive piezoelectric film may have a total light transmittance of 97% or less as long as the desired effect can be obtained sufficiently in the above case, but is not particularly limited. The closer the total light transmittance is to 100%, the better.
  • "transparency” refers to optical properties evaluated by total light transmittance
  • transparency or “highly transparent” means a state in which the total light transmittance is 90% or more. point to
  • a transparent conductive piezoelectric film comprises a transparent electrode layer.
  • the transparent electrode layer is a structure having transparency, conductivity and planar extent.
  • the shape of the transparent electrode layer when viewed in plan may be appropriately set according to the use of the transparent conductive piezoelectric film. Details of the transparent electrode layer will be described in ⁇ Specific Examples of Transparent Conductive Piezoelectric Film>.
  • the surface resistance value of the transparent electrode layer of the transparent conductive piezoelectric film may be determined according to the application.
  • the transparent conductive piezoelectric film may have a surface resistance value of 300 ⁇ /sq or more, 400 ⁇ /sq or more, or even 500 ⁇ /sq or more.
  • the surface resistance value may be less than 1700 ⁇ /sq.
  • the surface resistance value of the transparent electrode layer is within this range, it can be used for any device as a conductive film. Further, the surface resistance value can be less than 1000 ⁇ /sq. Since the surface resistance value is within this range, the transparent conductive piezoelectric film can be suitably used for devices such as actuators.
  • the transparent conductive piezoelectric film may be a laminated film formed by stacking a plurality of arbitrary layers.
  • a transparent conductive piezoelectric film is a laminated film having a structure in which a first transparent coating layer, a second transparent coating layer and a transparent electrode layer are laminated in this order on at least one side of a transparent piezoelectric film.
  • stacked in this order means a state in which the layers are arranged adjacent to each other in the listed order in a laminate including the above layers.
  • FIG. 1 shows a transparent conductive piezoelectric film 11 as an example of the transparent conductive piezoelectric film.
  • the transparent conductive piezoelectric film 11 is a laminated film in which a first transparent coating layer 2, a second transparent coating layer 3 and a transparent electrode layer 4 are laminated in this order on one surface of the transparent piezoelectric film 1.
  • the transparent conductive piezoelectric film 11 is not limited to the configuration shown in FIG. 1, and may further include another layer structure.
  • the transparent conductive piezoelectric film 11 may be a transparent conductive piezoelectric film in which the transparent piezoelectric film 1 and the first transparent coating layer 2 are overlaid with the third transparent coating layer 5 interposed therebetween. That is, the transparent conductive piezoelectric film may be provided with a third transparent coating layer 5 between the transparent piezoelectric film 1 and the first transparent coating layer 2 .
  • Such a transparent conductive piezoelectric film is shown as transparent conductive piezoelectric film 12 in FIG.
  • the transparent conductive piezoelectric film 12 is formed by stacking a third transparent coating layer 5, a first transparent coating layer 2, a second transparent coating layer 3 and a transparent electrode layer 4 on one side of the transparent piezoelectric film 1 in this order. It is a composed laminated film.
  • the transparent piezoelectric film 1 has a refractive index of 1.30 or more and less than 1.45
  • the first transparent coating layer 2 has a refractive index of 1.60 or more and less than 1.80
  • the refractive index of the second transparent coating layer 3 is 1.30 or more and 1.50 or less
  • the refractive index of the transparent electrode layer 4 is 1.80 or more and 2.20 or less.
  • the transparent conductive piezoelectric film 11 can be a transparent conductive piezoelectric film having a total light transmittance of 90% or more.
  • the refractive index of the third transparent coating layer 5 may be 1.45 or more and less than 1.60.
  • the transparent conductive piezoelectric film 12 can improve its transparency.
  • the "refractive index” refers to the refractive index at a wavelength of 589 nm.
  • the refractive indices of the first transparent coating layer 2 and the second transparent coating layer 3 were measured according to JIS K7142. Specifically, using an Abbe refractometer, measurement light with a wavelength of 589 nm is incident on each layer for each coating layer prepared experimentally, and the measurement is performed three times at 25.0 ⁇ 1.0 ° C. The average of the values was taken as the refractive index.
  • the refractive index of the transparent electrode layer 4 was determined by measuring psi ( ⁇ ) and delta ( ⁇ ) with a multi-incidence angle high-speed spectroscopic ellipsometer (M-2000 manufactured by JA Woollam), and then calculating the refractive index at a wavelength of 589 nm. Calculated.
  • the refractive index of the transparent piezoelectric film 1 was measured according to ASTM D542.
  • the thickness of the transparent electrode layer 4 is 5 nm or more and less than 20 nm. By setting the thickness of the transparent electrode layer 4 within this range, it is possible to impart suitable resistance and transparency to the transparent conductive piezoelectric film 11 .
  • each layer of the transparent conductive piezoelectric film 11 and the transparent conductive piezoelectric film 12 will be described in detail below.
  • the transparent conductive piezoelectric film 11 by setting the refractive index of each layer within the “further preferable” range described later, the transparent conductive piezoelectric film can be made with higher transparency.
  • the transparent piezoelectric film 1 included in the transparent conductive piezoelectric film 11 refers to a film that has piezoelectricity and is transparent.
  • the “transparent” of the transparent piezoelectric film 1 refers to the state of the film in which the total light transmittance is 80% or more.
  • the total light transmittance of the transparent piezoelectric film may be 80% or higher, preferably 85% or higher, and more preferably 90% or higher.
  • the refractive index of the transparent piezoelectric film 1 is, for example, 1.30 or more and less than 1.45.
  • the refractive index of the transparent piezoelectric film 1 may be within this range, preferably 1.34 or more, more preferably 1.36 or more.
  • the refractive index is preferably 1.44 or less, more preferably 1.43 or less.
  • the transparent piezoelectric film 1 is a resin film.
  • the resin in this embodiment may be any resin as long as the film has a piezoelectric characteristic represented by the piezoelectric constant d31 , and may be one type of resin or a combination of two or more types. Examples of resins satisfying the above conditions include fluororesin, polyamide 11, cellulose, polyurethane and polyurea.
  • the transparent piezoelectric film is made of fluororesin, it is possible to obtain a transparent conductive piezoelectric film that is excellent in transparency and piezoelectric properties represented by the piezoelectric constant d31 .
  • “made of fluororesin” means that the main component of the composition constituting the transparent piezoelectric film is fluororesin.
  • the phrase "a fluororesin is the main component” means that the fluororesin is the component with the largest amount in the composition.
  • the content of the fluororesin in the composition is preferably 51% by mass or more, more preferably 80% by mass or more, and particularly preferably 100% by mass. That is, it is particularly preferable that the transparent piezoelectric film 1 is a film made of fluororesin.
  • vinylidene fluoride resins are preferred.
  • vinylidene fluoride resins include vinylidene fluoride homopolymers and copolymers thereof.
  • the content of structural units derived from monomers other than vinylidene fluoride in the copolymer of vinylidene fluoride may be appropriately determined within a range in which properties according to the application of the transparent piezoelectric film can be exhibited.
  • Examples of monomers other than vinylidene fluoride in vinylidene fluoride copolymers include hydrocarbon-based monomers and fluorine compounds.
  • Examples of the hydrocarbon monomers include vinyl fluoride (VF), trifluoroethylene (TrFE), tetrafluoroethylene (TeFE), hexafluoropropene (HFP), 1-chloro-1-fluoro-ethylene ( 1,1-CFE), 1-chloro-2-fluoro-ethylene (1,2-CFE), 1-chloro-2,2-difluoroethylene (CDFE), chlorotrifluoroethylene (CTFE), trifluorovinyl monomers , 1,1,2-trifluorobutene-4-bromo-1-butene, 1,1,2-trifluorobutene-4-silane-1-butene, perfluoroalkyl vinyl ether, perfluoromethyl vinyl ether (PMVE), perfluoropropyl Fluoromonomers such as vinyl ethers (PPVE),
  • allyl glycidyl ether acrylic acid-based monomers, methacrylic acid-based monomers, and hydrocarbon-based monomers such as vinyl acetate.
  • trifluoroethylene, tetrafluoroethylene, and hexafluoropropene are preferred as monomers other than vinylidene fluoride in the copolymer.
  • the vinylidene fluoride copolymer is a vinylidene fluoride copolymer (VDF/TrFE) obtained by copolymerizing vinylidene fluoride and trifluoroethylene, and a vinylidene fluoride copolymer obtained by copolymerizing vinylidene fluoride and hexafluoropropene.
  • VDF/HFP vinylidene fluoride copolymers
  • VDF/TeFE binary copolymers
  • the binary copolymer preferably has a mixing ratio of vinylidene fluoride and comonomer of 50:50 to 90:10.
  • a vinylidene fluoride copolymer VDF/TeFP
  • VDF/TFE/HFP vinylidene fluoride copolymer
  • a ternary copolymer such as vinylidene fluoride copolymer (VDF/TFE/HFP) in which vinylidene fluoride, trifluoroethylene, and hexafluoropropene are copolymerized at a mixing ratio of 40:40:20. It may be a polymer.
  • homopolymers of vinylidene fluoride and copolymers of vinylidene fluoride and tetrafluoroethylene are preferably used.
  • the transparent piezoelectric film of the present embodiment may contain various additives within the range where the effects of the present embodiment can be obtained.
  • the additive may be one or more, examples of which include plasticizers, lubricants, crosslinkers, UV absorbers, pH adjusters, stabilizers, antioxidants, surfactants and pigments.
  • the thickness of the transparent piezoelectric film 1 in this embodiment can be appropriately determined depending on the application of the transparent conductive piezoelectric film 11 and within the range in which the effects of this embodiment can be obtained. If the thickness of the transparent piezoelectric film 1 is too thin, the mechanical strength may be insufficient. Sometimes. From such a viewpoint, the thickness of the transparent piezoelectric film 1 may be 10 ⁇ m or more, preferably 20 ⁇ m or more, and more preferably 30 ⁇ m or more. Also, the thickness of the transparent piezoelectric film 1 may be less than 200 ⁇ m, preferably 120 ⁇ m or less, and more preferably 70 ⁇ m or less.
  • the transparent electrode layer 4 in this embodiment is a layered electrode overlaid on the second transparent coating layer 3 .
  • the transparent electrode layer 4 in this embodiment has a structure that spreads in a plane and has conductivity and sufficient transparency, and can also be called a transparent conductive layer. Even if the material itself constituting the transparent electrode layer 4 does not have transparency, the layer should exhibit sufficient transparency in a structure in which the transparent electrode layer 4 can exhibit its function.
  • the transparent electrode layer 4 may be composed of a highly transparent conductive member or composition, or may be composed of a non-transparent conductive material that can exhibit sufficient transparency. It may be an ultra-thin or ultra-fine microstructure.
  • the transparent electrode layer 4 may be formed on a transparent substrate and adhered to the second transparent coating layer 3 together with the substrate.
  • the transparent electrode layer 4 may be arranged on at least one side of the transparent piezoelectric film 1 .
  • the transparent electrode layer 4 is arranged on at least one side of the second transparent coating layer 3. Just do it.
  • the material constituting the transparent electrode layer 4 is not limited, and at least selected from the group consisting of In, Sn, Zn, Ga, Sb, Ti, Si, Zr, Mg, Al, Au, Ag, Cu, Pd and W.
  • a metal oxide of one kind of metal is preferably used.
  • ITO, zinc oxide, antimony-tin composite oxide (ATO), or the like is preferably used as the metal oxide, and ITO is particularly preferably used.
  • the metal oxide may be doped with metal atoms shown in the above group, if necessary.
  • the transparent electrode layer 4 is a metal oxide
  • the metal oxide may become amorphous.
  • the fact that the transparent electrode layer 4 is made of an amorphous material can be confirmed by, for example, an observation image of a transmission electron microscope.
  • a material in which crystals other than microcrystals are not observed is called amorphous
  • a material in which crystal grains are observed is called crystalline.
  • the amorphousness of the metal oxide in the transparent electrode layer 4 is adjusted by whether or not a process for promoting crystallization in the production of the transparent electrode layer 4, such as annealing after forming the transparent electrode layer 4, is performed and the degree of implementation. It is possible to
  • the transparent electrode layer 4 is composed of an indium-tin composite oxide. In yet another aspect, the transparent electrode layer 4 is composed of an indium-tin composite oxide, and the peak of the indium-tin composite oxide is not detected in X-ray diffraction. According to this configuration, the transparent electrode layer 4 can be amorphous and have a refractive index within a suitable range.
  • the refractive index of the transparent electrode layer 4 is, for example, 1.80 or more and 2.20 or less.
  • the refractive index of the transparent electrode layer 4 is not limited as long as it is within this range, preferably 1.83 or more, more preferably 1.85 or more.
  • the refractive index of the transparent electrode layer 4 is preferably 2.00 or less, more preferably 1.94 or less.
  • the transparent conductive piezoelectric film including the transparent electrode layer 4 having a refractive index of 1.94 or less is a film produced without heating at a high temperature. Therefore, the transparency and color of the transparent piezoelectric film 1 are not impaired by the high-temperature treatment, and a suitable transparent conductive piezoelectric film can be obtained.
  • a transparent conductive piezoelectric film having a refractive index of 1.94 or less and including an amorphous transparent electrode layer 4 is preferable.
  • the material of the transparent electrode layer 4 is amorphous, the material layer 4 itself is a yellowish material.
  • the transparent conductive piezoelectric film 11 on which such a transparent electrode layer 4 is deposited tends to be a film having a tint even if other layers are transparent.
  • the transparent conductive piezoelectric film 11 according to one embodiment of the present invention by adjusting the refractive index of each layer, the transparent conductive piezoelectric film 11 with suitable optical properties can be achieved.
  • the thickness of the transparent electrode layer 4 may be 5 nm or more, preferably 7 nm or more, more preferably 8 nm or more. If the thickness of the transparent electrode layer 4 is too thin, the electrical resistance of the transparent conductive piezoelectric film 11 may increase, and discontinuous portions may be formed in the transparent electrode layer 4 . By ensuring that the thickness of the transparent electrode layer 4 is not less than the above lower limit, the transparent conductive piezoelectric film 11 can be a continuous film having good conductivity with a resistance of less than 1700 ⁇ /sq.
  • the thickness of the transparent electrode layer 4 may be less than 25 nm, preferably less than 20 nm, more preferably less than 15 nm. If the thickness of the transparent electrode layer 4 is too thick, the transparency may deteriorate. By not exceeding the above upper limit of the transparent electrode layer 4, the transparency of the transparent conductive piezoelectric film can be enhanced. Incidentally, the thickness of the transparent electrode layer 4 is obtained by the following method of obtaining from observation of the cross section of the transparent conductive piezoelectric film 11 .
  • a transparent conductive piezoelectric film is embedded in epoxy resin, and the epoxy resin mass is cut so that the cross section of the transparent conductive piezoelectric film is exposed.
  • a cross section of the exposed transparent conductive piezoelectric film was observed using a scanning electron microscope ("SU3800", manufactured by Hitachi High-Tech Co., Ltd.) under conditions of an acceleration voltage of 3.0 kV and a magnification of 50,000 times. Measure the thickness of each coating layer and transparent electrode layer.
  • the thickness of each coating layer and transparent electrode layer is measured at any two points, and the average value of the measured values obtained for each layer is taken as the thickness of each layer. do.
  • the interfaces between the layers are observed as substantially smooth lines. In this case, the thickness of each layer is measured by measuring the distance between the lines.
  • the thickness of the transparent electrode layer 4 is important from the viewpoint of maintaining the conductivity and improving the transparency of the transparent conductive piezoelectric film 11 . Furthermore, the preferred combination of the refractive index and the thickness of each of the first transparent coating layer, the second transparent coating layer, the transparent electrode layer, and the optionally provided third transparent coating layer of the transparent conductive piezoelectric film 11 allows the interfacial reflection of each layer. are preferably adjusted so that they cancel each other out, and the transparency is further improved.
  • the first transparent coating layer 2 in this embodiment is a layer located between the transparent piezoelectric film 1 and the second transparent coating layer 3 .
  • the refractive index of the first transparent coating layer 2 is, for example, 1.60 or more and less than 1.80.
  • the refractive index of the first transparent coating layer 2 may be within this range, preferably 1.63 or more, more preferably 1.65 or more.
  • the refractive index of the first transparent coating layer 2 is preferably 1.75 or less, more preferably 1.72 or less.
  • the material of the first transparent coating layer 2 may be appropriately selected from all available materials as long as it satisfies such a refractive index.
  • the material may be an inorganic material, an organic material, an inorganic-organic mixed material, or a composite material thereof.
  • it may be a single material, a mixed material of two or more materials, or a composite material, but from the viewpoint of improving the transparency of the transparent conductive piezoelectric film, a single material or a composite material further containing metal oxide particles described later.
  • the material of the coating layer may be the material of the hard coat layer. Examples of such materials include melamine resins, urethane resins, (meth)acrylic acid ester resins, silane compounds and metal oxides.
  • (meth)acrylic acid is a generic term for acrylic acid and methacrylic acid, and means one or both of them.
  • (meth)acrylic acid ester resins are preferable from the viewpoints of sufficient transparency, wide variety of materials, and low raw material costs.
  • the refractive index of the first transparent coating layer 2 may be adjusted by adding metal oxide particles to the above materials.
  • the refractive index of the metal oxide fine particles is preferably 1.50 or more.
  • the metal oxide fine particles include aluminum oxide, titanium oxide, zirconium oxide, zinc oxide and tin oxide, with titanium oxide and zirconium oxide being preferred.
  • the first transparent coating layer 2 may further contain a material for exhibiting any function.
  • the first transparent coating layer 2 may contain an antistatic agent.
  • antistatic agents include surfactants, antimony pentoxide, indium-tin composite oxide (ITO) and conductive polymers.
  • the preferred thickness of the first transparent coating layer 2 varies depending on the presence or absence of the third transparent coating layer 5 in the transparent conductive piezoelectric film.
  • the thickness of the first transparent coating layer 2 may be 600 nm or more, preferably 700 nm or more, and more preferably 800 nm or more.
  • the thickness of the first transparent coating layer 2 may be less than 1100 nm, preferably 1000 nm or less, and more preferably 900 nm or less.
  • the first transparent coating layer should not only have a predetermined refractive index to enhance the transparency of the transparent conductive piezoelectric film, but also the transparent piezoelectric film 1. It is also required to prevent scratches and irregularities on the surface of the product.
  • the thickness of the first transparent coating layer 2 is not less than the lower limit, scratches and irregularities on the surface of the transparent piezoelectric film 1 can be prevented, so that the transparency of the transparent piezoelectric film 1 is enhanced.
  • it is preferable that the thickness of the first transparent coating layer 2 does not exceed the upper limit, from the viewpoint of thinning the transparent piezoelectric film and enhancing the transparency of the film.
  • the thickness of the first transparent coating layer 2 may be 60 nm or more, preferably 70 nm or more, and more preferably 85 nm or more. Also, the thickness of the first transparent coating layer 2 may be less than 200 nm, preferably 180 nm or less, more preferably 170 nm or less. By setting the thickness of the first transparent coating layer within this range, transparency can be imparted to the transparent conductive piezoelectric film 11 .
  • the second transparent coating layer 3 in this embodiment is a layer located between the first transparent coating layer 2 and the transparent electrode layer 4 .
  • the refractive index of the second transparent coating layer 3 is, for example, 1.30 or more and 1.50 or less.
  • the refractive index of the second transparent coating layer 3 may be within this range, preferably 1.35 or more, more preferably 1.37 or more.
  • the refractive index of the second transparent coating layer 3 is preferably 1.48 or less, more preferably 1.47 or less.
  • the material for the second transparent coating layer 3 may be appropriately selected from all available materials as long as it satisfies such a refractive index.
  • a material may be appropriately selected from the materials exemplified as the material of the first transparent coating layer 2 so as to have an appropriate refractive index.
  • the material of the second transparent coating layer 3 may contain other materials necessary to constitute the transparent coating layer, similar to the materials described for the material of the first transparent coating layer 2 .
  • one or more metal fluorides or silicon dioxide selected from the group consisting of NaF, Na 3 AlF 6 , LiF, MgF 2 , CaF 2 and BaF 2 can be included to adjust the refractive index.
  • silicon dioxide is preferred.
  • the thickness of the second transparent coating layer 3 may be 10 nm or more, preferably 20 nm or more, and more preferably 30 nm or more.
  • the thickness of the second transparent coating layer 3 may be 100 nm or less, preferably 95 nm or less, and more preferably 90 nm or less.
  • the third transparent coating layer 5 is an optional layer provided on the transparent conductive piezoelectric film. If the third transparent coating layer 5 is present, the third transparent coating layer 5 is the film layer that is in direct contact with the transparent piezoelectric film 1 . For example, a layer located between the transparent piezoelectric film 1 and the first transparent coating layer 2 , such as the transparent conductive piezoelectric film 12 . Also, when the first transparent coating layer 2 is present only on one side of the transparent piezoelectric film 1 , the other side of the transparent piezoelectric film 1 may be provided with the third transparent coating layer 5 .
  • the transparent conductive piezoelectric film 11 may have a third transparent coating layer 5 on both sides of the transparent piezoelectric film 1 .
  • the third transparent coating layer 5 may have a refractive index of 1.45 or higher, preferably 1.48 or higher, and more preferably 1.50 or higher. Also, the third transparent coating layer 5 may have a refractive index of less than 1.60, preferably less than 1.58, more preferably less than 1.55.
  • the material for the third transparent coating layer 5 may be appropriately selected from all available materials as long as it satisfies such a refractive index.
  • a material may be appropriately selected from the materials exemplified as the material of the first transparent coating layer 2 so as to have an appropriate refractive index.
  • the third transparent coating layer 5 may be a transparent surface protection layer for scratch prevention, which is also called a hard coat layer. It is preferable that the material has a suitable refractive index and is excellent in abrasion resistance.
  • Inorganic particles, polymer beads, and the like may be added to the material of the third transparent coating layer 5 from the viewpoint of blocking prevention and adhesion between films.
  • examples of inorganic particles that can be used include synthetic silica, talc, diatomaceous earth, calcium carbonate, feldspars, quartz, etc. Synthetic silica is particularly preferably used from the viewpoint of improving the quality of plastic films.
  • the thickness of the third transparent coating layer 5 may be 500 nm or more, preferably 700 nm or more, and more preferably 900 nm or more. When the thickness of the third transparent coating layer 5 does not fall below the lower limit, the effect of protecting the transparent piezoelectric film 1 can be expected.
  • the thickness of the third transparent coating layer 5 may be 1400 nm or less, preferably 1200 nm or less, and more preferably 1100 nm or less, from the viewpoint of thinning the film. Since the thickness of the third transparent coating layer does not exceed the upper limit, it is possible to suppress the deterioration of the piezoelectric properties represented by the piezoelectric constant d31.
  • the transparent conductive piezoelectric film 12 with improved transparency can be obtained.
  • the transparent conductive piezoelectric film has a high total light transmittance and a suppressed tint from the viewpoint of realizing stable transparency.
  • the transparent electrode layer is made of an amorphous material
  • the yellowness of the transparent conductive piezoelectric film may be evaluated using the Yellow Index (also referred to as "YI value").
  • the YI value is a value calculated by the method described in JIS K7373 using the XYZ color system measured according to JIS Z8722.
  • the Yellow Index of the transparent conductive piezoelectric film may be 7 or less, preferably 6.5 or less, and more preferably 6 or less. It is preferable that the YI value of the transparent conductive piezoelectric film is equal to or less than the upper limit, because yellowness is suppressed.
  • the YI value may be -7 or more, preferably -5 or more, and more preferably -3 or more. It is preferable that the YI value of the transparent conductive piezoelectric film is equal to or higher than the lower limit, because the bluish tint of the transparent conductive piezoelectric film is suppressed. It should be noted that the closer the YI value is to 0, the better.
  • the a * value in the L * a * b * color system measured in conformity with JIS Z8722 may be used as a color tone other than yellowness.
  • the transparent conductive piezoelectric film may have an a * value of ⁇ 1.5 or more, preferably ⁇ 1.2 or more, and more preferably ⁇ 1.0 or more. When the a * value does not fall below the lower limit, it can be determined that the green tint is suppressed. Also, a * may be 1.0 or less, preferably 0.8 or less, and more preferably 0.7 or less. When the a * value of the transparent conductive piezoelectric film is within the range, it can be determined that the red color is suppressed.
  • a * value can be measured by a known method described in JIS Z8722 using, for example, a spectral colorimeter.
  • a device comprises a transparent conductive piezoelectric film according to one embodiment described above.
  • the device may be anything as long as it comprises the transparent conductive piezoelectric film of this embodiment.
  • the location and number of transparent conductive piezoelectric films can be determined appropriately depending on the application or intended function of the device.
  • a transparent conductive piezoelectric film according to one embodiment has suitable conductivity and a high piezoelectric constant as described above. Also, each layer of the transparent conductive piezoelectric film can be made into ink and can be formed by coating or printing. In addition, the transparent conductive piezoelectric film according to one embodiment has chemical stability and film flexibility. Based on these characteristics, the transparent conductive piezoelectric film according to one embodiment is being studied for application to devices such as flexible sensors such as pressure sensors and vibration sensors, energy harvesting elements, and actuators. When the transparent conductive piezoelectric film according to one embodiment is applied to a device, the transparent conductive piezoelectric films may be adhered to each other to form a transparent conductive piezoelectric body having a bimorph structure, which may be applied to the device. A transparent conductive piezoelectric material having a bimorph structure is preferable from the viewpoint of increasing the amount of displacement with respect to an applied voltage.
  • the transparent adhesive sheet is adhered not only on an arbitrary transparent coating layer but also on the transparent coating layer via the transparent adhesive sheet in the production thereof. may be formed on other layers that In this case, the transparent adhesive sheet layer may or may not be on the transparent coating layer side.
  • a device that incorporates a transparent conductive piezoelectric film according to one embodiment can eliminate electrode layers made of, for example, PET/ITO that are included in conventional devices because the transparent conductive piezoelectric film also functions as an electrode. is. Therefore, the layer structure of the device can be simplified more than before.
  • the method for manufacturing the transparent conductive piezoelectric film 11 comprises a first transparent coating layer 2, a second transparent coating layer 3, and a transparent electrode layer 4, which are laminated in this order on at least one surface of the transparent piezoelectric film 1. It is a method for manufacturing a laminated film.
  • the manufacturing method includes a first step of manufacturing a transparent piezoelectric film 1 forming a film having a refractive index of 1.30 or more and less than 1.45; As described above, the second step of forming the first transparent coating layer 2 having a refractive index of less than 1.80 and the second transparent coating layer 3 having a refractive index of 1.30 or more and less than 1.50 are formed on the surface of the first transparent coating layer 2. and a fourth step of forming a transparent electrode layer 4 having a refractive index of 1.80 or more and 2.20 or less on the surface of the second transparent coating layer 3 .
  • the first step may be a step of producing the transparent piezoelectric film 1, and the steps may be changed or added as appropriate according to the type of the transparent piezoelectric film 1 to be produced.
  • a step of producing a resin film by a conventionally known method such as a casting method, a hot press method, and a melt extrusion method, a step of stretching the resin film, and a step of polarizing the non-polarized resin film are continued.
  • the transparent piezoelectric film 1 can be produced by carrying out the above steps.
  • the second to fourth steps can be suitably carried out using known coating methods such as wet coating method and dry coating method.
  • the wet coating method forms a layer by applying a material, so it is suitable for forming a thick layer. Suitable for forming thin layers.
  • the second step is to form the first transparent coating layer.
  • the second step is preferably carried out by a wet coating method in terms of productivity and manufacturing cost.
  • the material for the first transparent coating layer may be applied to at least one surface of the transparent piezoelectric film 1 produced in the first step.
  • the coating method may be a conventionally known method and is not particularly limited.
  • the wet coating method may be a known method, and typical methods include roll coating, spin coating, dip coating, gravure coating, and the like. Among them, methods capable of forming layers continuously, such as the roll coating method and the gravure coating method, are preferable from the viewpoint of productivity.
  • a bar coater, a gravure coater, or the like, for example, may be used to apply the material of the first transparent coating layer 2 .
  • After coating the material it may be dried at 50° C. to 180° C. for 0.5 to 60 minutes.
  • the dried coating of the first transparent coating layer 2 may be solidified by UV irradiation.
  • a UV irradiation device may be used to irradiate UV with an integrated light quantity of 50 to 1200 mJ/cm 2 .
  • Conditions such as the apparatus used in the second step, the concentration of the material, and the temperature may be appropriately changed with reference to the material, film thickness, and the like of the first transparent coating layer 2 .
  • the third step is to form the second transparent coating layer.
  • a coating of the material of the second transparent coating layer 3 may be applied to the first transparent coating layer 2 produced in the second step by known methods.
  • the material for the second transparent coating layer 3 may be applied using the same wet coating method as for the first transparent coating layer 2 .
  • the third step is carried out by a wet coating method, the conditions such as the device, material concentration and temperature in the third step may be the same as those in the second step.
  • the thickness of the second transparent coating layer 3 can be adjusted, for example, by adjusting the concentration of the material.
  • the film thickness of the second transparent coating layer 3 can be adjusted by adjusting the sputtering time, for example.
  • the material for the second transparent coating layer 3 may be attached onto the first transparent coating layer 2 produced in the second step by a known dry coating method.
  • Typical dry coating methods include, for example, sputtering, vacuum deposition, ion plating, and the like. These methods may be appropriately selected according to the required film thickness.
  • the target material when the sputtering method is adopted as the third step, includes an inorganic substance that constitutes the second transparent coating layer, such as Si.
  • the sputtering gas include an inert gas such as Ar.
  • a reactive gas such as oxygen gas can be used together as necessary.
  • the fourth step is the step of forming a transparent electrode layer.
  • the transparent electrode layer 4 may be formed by a known method on the second transparent coating layer 3 produced in the third step.
  • the transparent electrode layer 4 may be formed by depositing the material of the transparent electrode layer 4 by, for example, a sputtering method, a vacuum deposition method, an ion plating method, or the like.
  • the material for the transparent electrode layer may be applied using a wet coating method in the same manner as the second transparent coating layer 3 .
  • the target material includes the above-mentioned inorganic substances constituting the transparent electrode layer 4, preferably ITO.
  • the tin oxide concentration of ITO is, for example, 0.5% by mass or more, preferably 2% by mass or more, and is, for example, 15% by mass or less, preferably 13% by mass or less, and more preferably 7% by mass. % or less.
  • the sputtering gas examples include inert gases such as Ar.
  • a reactive gas such as oxygen gas can be used together as necessary.
  • the flow rate ratio of the reactive gas is not particularly limited, but is, for example, 0.1 flow % or more and 5 flow % or less with respect to the total flow rate of the sputtering gas and the reactive gas.
  • the atmospheric pressure during sputtering is, for example, 1 Pa or less, preferably 0.7 Pa or less, from the viewpoints of suppressing a decrease in sputtering rate, discharge stability, and the like.
  • the power source used in the sputtering method may be, for example, a DC power source, an AC power source, an MF power source, an RF power source, or a combination thereof.
  • the manufacturing method of the present embodiment may include further steps as long as it includes the first to fourth steps.
  • a third transparent coating layer 5 may be formed on the transparent piezoelectric film 1 between the first step and the second step.
  • the third transparent coating layer 5 may be formed by applying the material for the third transparent coating layer 5 onto the transparent piezoelectric film 1 produced in the first step by a known method.
  • a step of adding other layer configurations to the transparent conductive piezoelectric film 11 may be added.
  • a step of corona-treating the transparent piezoelectric film 1 to enhance adhesion to the first transparent coating layer 2 may be added.
  • the transparent conductive piezoelectric film 11 having high transparency and suitable color can be manufactured.
  • the transparent electrode layer 4 does not need to be annealed after the fourth step. Since the color of the transparent piezoelectric film 1 is not impaired by not performing the annealing treatment, the transparent conductive piezoelectric film 11 that can be suitably used for devices such as displays can be produced.
  • the transparent conductive piezoelectric film according to aspect 1 has a piezoelectric constant d31 of 10 pC/N or more and 40 pC/N or less, a total light transmittance of 90% or more, and includes a transparent electrode layer.
  • a transparent conductive piezoelectric film has excellent piezoelectric properties, transparency and conductivity, and can be suitably used for a wide range of devices.
  • the transparent conductive piezoelectric film according to aspect 2 is the transparent conductive piezoelectric film in aspect 1, wherein at least one surface of the transparent conductive piezoelectric film is composed of a transparent electrode layer, and the surface resistance value of the surface is 300 ⁇ /sq or more and less than 1700 ⁇ /sq. be.
  • a transparent conductive piezoelectric film can be used for any device as a conductive film.
  • the transparent conductive piezoelectric film according to Mode 3 has a surface resistance value of less than 1000 ⁇ /sq in Mode 2.
  • Such a transparent conductive piezoelectric film can also be suitably used for devices such as actuators.
  • the transparent conductive piezoelectric film according to aspect 4 in any one of aspects 1 to 3, has a Yellow Index of 7 or less calculated by the method described in JIS K7373 using the XYZ color system measured in accordance with JIS Z8722. is.
  • Such a transparent conductive piezoelectric film is preferable because it has a suppressed yellow tint.
  • the transparent conductive piezoelectric film according to aspect 5, in any one of aspects 1 to 4, has L * a * b* a* in the color system measured in accordance with JIS Z8722 of ⁇ 1.5 or more; 0 or less.
  • Such a transparent conductive piezoelectric film is preferable because it suitably suppresses green and red tints.
  • the transparent conductive piezoelectric film according to Mode 6 is, in any one of Modes 1 to 5, provided on at least one surface of the transparent piezoelectric film with a third transparent coating layer, a first transparent coating layer, a second transparent coating layer, and the transparent electrode layer are stacked in this order, the transparent piezoelectric film has a refractive index of 1.30 or more and less than 1.45, and the third transparent coating layer has a refractive index of 1.45 and less than 1.60, the first transparent coating layer has a refractive index of 1.60 or more and less than 1.80, and the second transparent coating layer has a refractive index of 1.30 or more and 1.50 or less.
  • the refractive index of the transparent electrode layer is 1.80 or more and 2.20 or less
  • the thickness of the first transparent coating layer is 60 nm or more and less than 200 nm
  • the thickness of the second transparent coating layer is 10 nm or more. 100 nm or less
  • the thickness of the third transparent coating layer is 500 nm or more and 1400 nm or less.
  • the transparent conductive piezoelectric film according to mode 7 is the transparent conductive piezoelectric film according to mode 6, wherein the transparent conductive piezoelectric film comprises the third transparent coating layer, the first transparent coating layer, the second transparent coating layer, and the second transparent coating layer on one surface of the transparent piezoelectric film.
  • a transparent coating layer and the transparent electrode layer are laminated in this order, and another third transparent coating layer is provided on the other surface of the transparent piezoelectric film. This configuration can improve the transparency of the transparent conductive piezoelectric film.
  • the transparent conductive piezoelectric film according to Mode 8 is, in any one of Modes 1 to 5, a first transparent coating layer, a second transparent coating layer, and a transparent electrode layer in this order on at least one surface of the transparent piezoelectric film.
  • the transparent piezoelectric film has a refractive index of 1.30 or more and less than 1.45, and the first transparent coating layer has a refractive index of 1.60 or more and less than 1.80.
  • the refractive index of the second transparent coating layer is 1.30 or more and 1.50 or less
  • the refractive index of the transparent electrode layer is 1.80 or more and 2.20 or less
  • the first transparent coating layer The thickness is 600 nm or more and less than 1100 nm
  • the thickness of the second transparent coating layer is 10 nm or more and 100 nm or less.
  • the transparent conductive piezoelectric film according to Mode 9 is the transparent conductive piezoelectric film according to Mode 7, wherein the transparent conductive piezoelectric film comprises the first transparent coating layer, the second transparent coating layer and the transparent electrode on one surface of the transparent piezoelectric film.
  • the layers are stacked in this order, and a third transparent coating layer is provided on the other surface of the transparent piezoelectric film, and the refractive index of the third transparent coating layer is 1.45 or more and less than 1.60. and the thickness of the third transparent coating layer is 500 nm or more and 1400 nm or less. This configuration can improve the transparency of the transparent conductive piezoelectric film.
  • the transparent electrode layer has a thickness of 7 nm or more and less than 20 nm. With this configuration, the resistance of the transparent conductive piezoelectric film can be reduced to a preferable range.
  • a transparent conductive piezoelectric film according to Mode 11 is the transparent conductive piezoelectric film according to any one of Modes 6 to 10, wherein the transparent piezoelectric film contains a fluororesin as a main component. With this configuration, a transparent piezoelectric film having a preferable refractive index can be obtained.
  • the transparent electrode layer has a refractive index of 1.94 or less. Since such a transparent conductive piezoelectric film is a film produced without heating at a high temperature, it is suitable in that the color of the transparent piezoelectric film is not impaired.
  • a device according to aspect 13 is a device comprising the transparent conductive piezoelectric film according to any one of aspects 1 to 12.
  • the manufacturing method according to aspect 14 is a laminated film in which a first transparent coating layer, a second transparent coating layer, and a transparent electrode layer are laminated in this order on at least one surface of a transparent piezoelectric film.
  • a manufacturing method comprising: a first step of manufacturing the transparent piezoelectric film forming a film having a refractive index of 1.30 or more and less than 1.45; A second step of forming the first transparent coating layer having a refractive index of less than 1.80, and forming the second transparent coating layer having a refractive index of 1.30 or more and less than 1.50 on the surface of the first transparent coating layer. and a fourth step of forming the transparent electrode layer having a refractive index of 1.80 or more and 2.20 or less on the surface of the second transparent coating layer.
  • Example 1 [Production of transparent conductive piezoelectric film] ⁇ Example 1> (First step: production of transparent piezoelectric film) A resin film (thickness: 120 ⁇ m) molded from polyvinylidene fluoride (manufactured by Kureha Co., Ltd.) having an inherent viscosity of 1.3 dl/g was stretched at a draw ratio of 4.2 times. After the stretching, the film was passed through polarization rolls for polarization treatment to obtain a piezoelectric film. At that time, the DC voltage was applied while being increased from 0 kV to 11.0 kV to perform the polarization treatment. The polarized film was further heat-treated at 130° C. for 1 minute to obtain a transparent piezoelectric film having a refractive index of 1.42 and a thickness of 40 ⁇ m.
  • amorphous silica-containing UV-curable resin composition made of an acrylic resin was applied to the upper surface (side A) of the transparent piezoelectric film, dried at 80°C, and then irradiated with UV rays at an integrated light intensity of 400 mJ/cm 2 .
  • a tri-transparent coating layer (thickness 1000 nm, refractive index 1.52) was formed.
  • a third transparent coating layer (thickness: 1000 nm, refractive index: 1.52) was also formed on the lower surface (B surface) of the transparent piezoelectric film in the same manner.
  • an ultraviolet curable resin composition containing zirconium oxide particles is applied to the upper surface of the third transparent coating layer (side A), dried at 80° C., and irradiated with ultraviolet rays at an integrated light amount of 400 mJ/cm 2 , A first transparent coating layer (thickness 100 nm, refractive index 1.65) was formed.
  • a hollow silica-containing UV-curable resin composition made of an acrylic resin is applied, dried at 80° C., and then irradiated with UV rays at an integrated light amount of 400 mJ/cm 2 .
  • a transparent coating layer (thickness 44 nm, refractive index 1.37) was formed.
  • a transparent electrode layer having a refractive index of 1 is formed by a reactive sputtering method using a sintered material containing 97% by mass of indium oxide and 3% by mass of tin oxide as a target.
  • An ITO film having a thickness of 0.88 and a thickness of 19 nm was formed.
  • a transparent conductive piezoelectric film was obtained, and the obtained transparent conductive piezoelectric film was designated as Example 1.
  • Example 2 A transparent conductive piezoelectric film was obtained in the same manner as in Example 1, except that the thickness of the transparent electrode layer was 12 nm. The obtained transparent conductive piezoelectric film was designated as Example 2.
  • Example 3 A transparent conductive piezoelectric film was obtained in the same manner as in Example 1, except that the thickness of the transparent electrode layer was 8 nm. The obtained transparent conductive piezoelectric film was designated as Example 3.
  • Example 4 A transparent conductive piezoelectric film was obtained in the same manner as in Example 2, except that the thickness of the second coating layer was 81 nm. The obtained transparent conductive piezoelectric film was designated as Example 4.
  • Example 5 A first transparent coating layer, a second transparent coating layer, and a transparent electrode layer were formed in this order on the A side of the transparent piezoelectric film without forming the third transparent coating layer on the A side and the B side of the transparent piezoelectric film.
  • a transparent conductive piezoelectric film was obtained in the same manner as in Example 2, except that the thickness of the first transparent coating layer was 850 nm, the refractive index was 1.70, and the thickness of the second transparent coating layer was 67 nm. The obtained transparent conductive piezoelectric film was designated as Example 5.
  • Example 6 A transparent conductive piezoelectric film was obtained in the same manner as in Example 2, except that the thickness of the first transparent coating layer was 120 nm, the refractive index was 1.70, and the thickness of the second coating layer was 50 nm. The obtained transparent conductive piezoelectric film was designated as Example 6.
  • Example 7 A transparent conductive piezoelectric film was obtained in the same manner as in Example 2, except that the thickness of the first transparent coating layer was 90 nm, the refractive index was 1.75, and the thickness of the second coating layer was 49 nm. The obtained transparent conductive piezoelectric film was designated as Example 7.
  • Example 8 A transparent conductive piezoelectric film was obtained in the same manner as in Example 6, except that the thickness of the first transparent coating layer was 163 nm and the thickness of the second transparent coating layer was 88 nm. The obtained transparent conductive piezoelectric film was designated as Example 8.
  • Example 9 (Formation of first transparent coating layer) A third transparent coating layer was formed on both sides of the transparent piezoelectric film in the same manner as in Example 1, and a first transparent coating layer (thickness: 100 nm, refractive index: 1.65) was further formed on the A side.
  • a SiO2 film was formed on the first transparent coating layer by an AC magnetron sputtering method using Si as a target material. Specifically, after the inside of the chamber was evacuated to 7 ⁇ 10 ⁇ 4 Pa or less, a mixed gas of Ar gas and oxygen gas was introduced into the chamber to deposit a SiO 2 film with a thickness of 25 nm, A second transparent coating layer (thickness 25 nm, refractive index 1.46) was formed.
  • Example 9 A transparent electrode layer was formed on the second transparent coating layer in the same manner as in Example 1, except that an ITO film with a thickness of 19 nm was used. Thus, a transparent conductive piezoelectric film was obtained, and the obtained transparent conductive piezoelectric film was designated as Example 9.
  • Example 10 A transparent conductive piezoelectric film was obtained in the same manner as in Example 9, except that the thickness of the first transparent coating layer was 105 nm and the refractive index was 1.70. The obtained transparent conductive piezoelectric film was designated as Example 10.
  • Example 11 A transparent conductive piezoelectric film with improved d31 was obtained in the same manner as in Example 10, except that the DC voltage was changed to 11.5 kV in the first step.
  • the obtained transparent conductive piezoelectric film was designated as Example 11.
  • Example 12 A transparent conductive piezoelectric film was obtained in the same manner as in Example 1, except that the thickness of the first transparent coating layer was 99 nm, the thickness of the second transparent coating layer was 81 nm, and the thickness of the transparent electrode layer was 5 nm.
  • the obtained transparent conductive piezoelectric film was designated as Example 11.
  • Example 1 A conductive piezoelectric film was obtained in the same manner as in Example 1, except that the third transparent coating layer, the first transparent coating layer, and the second transparent coating layer were not formed. The resulting conductive piezoelectric film was designated as Comparative Example 1.
  • Example 2 A conductive piezoelectric film was obtained in the same manner as in Example 1, except that the thickness of the second transparent coating layer was 81 nm and the thickness of the transparent electrode layer was 27 nm. The resulting conductive piezoelectric film was designated as Comparative Example 2.
  • Example 4 A conductive piezoelectric film was obtained in the same manner as in Example 1, except that the refractive index of the first transparent coating layer was 1.52, the refractive index of the second transparent coating layer was 1.40, and the thickness was 80 nm. The obtained conductive piezoelectric film was designated as Comparative Example 4.
  • Comparative Example 5 A conductive piezoelectric film was obtained in the same manner as in Comparative Example 4, except that the second transparent coating layer was not formed. The resulting conductive piezoelectric film was designated as Comparative Example 5.
  • Example 6 A conductive piezoelectric film was obtained in the same manner as in Example 10, except that the thickness of the second transparent coating layer was 28 nm, the refractive index was 1.52, and the thickness of the transparent electrode layer was 12 nm. The resulting conductive piezoelectric film was designated as Comparative Example 6.
  • Comparative Example 7 A conductive piezoelectric film was obtained in the same manner as in Comparative Example 6, except that the second transparent coating layer had a thickness of 111 nm and a refractive index of 1.40. The resulting conductive piezoelectric film was designated as Comparative Example 7.
  • ⁇ Comparative Example 8> The thickness of the first transparent coating layer was 40 ⁇ m, the refractive index was 1.55, the thickness of the second transparent coating layer was 40 ⁇ m, and sputtering was performed using indium oxide containing 36% by mass of tin oxide as a target.
  • a conductive piezoelectric film was obtained in the same manner as in Example 9. The resulting conductive piezoelectric film was designated as Comparative Example 8.
  • Example 9 A conductive piezoelectric film was obtained in the same manner as in Example 10, except that the thickness of the first coating layer was changed to 201 nm. The resulting conductive piezoelectric film was designated as Comparative Example 9.
  • the thicknesses of the transparent coating layer and the transparent electrode layer constituting the transparent conductive piezoelectric films and conductive piezoelectric films of Examples 1 to 12 and Comparative Examples 1 to 9 (hereinafter also simply referred to as "conductive piezoelectric films") It was obtained by a method based on observation with a microscope. In this method, first, a transparent conductive piezoelectric film is embedded in an epoxy resin, and the epoxy resin block is cut so that a section of the transparent conductive piezoelectric film is exposed.
  • a section of the exposed transparent conductive piezoelectric film is observed with a scanning electron microscope ("SU3800", manufactured by Hitachi High-Tech Co., Ltd.) under conditions of an acceleration voltage of 3.0 kV and a magnification of 50,000. Then, the thickness of the transparent conductive piezoelectric film and the individual films or layers in the transparent conductive piezoelectric film are measured.
  • SU3800 scanning electron microscope
  • Table 1 shows the refractive index of each layer of the conductive piezoelectric films of Examples 1 to 12 and Comparative Examples 1 to 9.
  • Table 2 shows the thickness of each layer of the conductive piezoelectric films of Examples 1 to 12 and Comparative Examples 1 to 9.
  • piezoelectric constant d 31 values The piezoelectric constant d31 of each of the conductive piezoelectric films of Examples 1 to 12 and Comparative Examples 1 to 9 was calculated by the following formula after measuring the electric charge according to the tensile stress using a force gauge, electric stand, and electrometer.
  • d 31 (Q/A) (t ⁇ w/F) where Q is the charge, A is the electrode area, t is the thickness of the conductive piezoelectric film, w is the width of the conductive piezoelectric film, and F is the force applied to the conductive piezoelectric film.
  • a test piece used for the measurement was a conductive piezoelectric film having aluminum electrodes formed on its front and back surfaces by a vapor deposition method. If the piezoelectric constant d31 value is 10 pC/N or more and 40 pC/N or less, it can be judged that there is no practical problem in the application of the device.
  • Total light transmittance The total light transmittance of each of the conductive piezoelectric films of Examples 1 to 12 and Comparative Examples 1 to 9 was measured using a haze meter ("NDH7000SP II", manufactured by Nippon Denshoku Industries Co., Ltd.) according to JIS K7361-1. Measured based on If the total light transmittance is 90% or more, there is no practical problem in the application of the device, and the higher the better.
  • Yellow Index Yellow Index (YI value) is a spectrocolorimeter ("SD7000", manufactured by Nippon Denshoku Industries Co., Ltd.) using an XYZ color system measured by a method conforming to JIS Z8722, using the method described in JIS K7373. calculated with
  • Table 3 shows the results of the above evaluation.
  • the conductive piezoelectric films of Examples 1 to 12 all have practically no problem physical properties in device applications, and also have high transparency.
  • the total light transmittances of the conductive piezoelectric films of Comparative Examples 1 to 9 were all 90% or less.
  • the present invention can be used for devices that require piezoelectric properties.

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PCT/JP2022/032536 2021-10-22 2022-08-30 透明導電圧電フィルム、デバイス、および透明導電圧電フィルムの製造方法 Ceased WO2023067899A1 (ja)

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CN202280063215.0A CN117999869A (zh) 2021-10-22 2022-08-30 透明导电压电膜、器件以及透明导电压电膜的制造方法
EP22883211.9A EP4422380B1 (en) 2021-10-22 2022-08-30 Transparent conductive piezoelectric film, device, and production method for transparent conductive piezoelectric film
KR1020247012555A KR102814226B1 (ko) 2021-10-22 2022-08-30 투명 도전 압전 필름, 디바이스 및 투명 도전 압전 필름의 제조방법
JP2023554970A JP7624084B2 (ja) 2021-10-22 2022-08-30 透明導電圧電フィルム、デバイス、および透明導電圧電フィルムの製造方法

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2024203685A1 (ja) * 2023-03-24 2024-10-03 株式会社クレハ 積層圧電体及びその製造方法
WO2024219145A1 (ja) * 2023-04-19 2024-10-24 株式会社クレハ 積層圧電体及びその製造方法

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002120311A (ja) * 2000-10-13 2002-04-23 Jsr Corp 構造体
JP2004098420A (ja) * 2002-09-09 2004-04-02 Dainippon Printing Co Ltd 透明積層フィルム、偏光板、液晶表示素子及び液晶表示装置
JP2017074792A (ja) 2016-12-28 2017-04-20 日東電工株式会社 透明導電性フィルム及びタッチパネル
WO2017170616A1 (ja) * 2016-03-28 2017-10-05 ダイキン工業株式会社 バイモルフ型圧電フィルム
JP2019096680A (ja) * 2017-11-21 2019-06-20 日東電工株式会社 圧電フィルムおよび圧電センサ

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP6547627B2 (ja) * 2013-10-29 2019-07-24 ダイキン工業株式会社 圧電フィルム
JP6327334B2 (ja) * 2014-02-26 2018-05-23 ダイキン工業株式会社 バイモルフ型圧電フィルム

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002120311A (ja) * 2000-10-13 2002-04-23 Jsr Corp 構造体
JP2004098420A (ja) * 2002-09-09 2004-04-02 Dainippon Printing Co Ltd 透明積層フィルム、偏光板、液晶表示素子及び液晶表示装置
WO2017170616A1 (ja) * 2016-03-28 2017-10-05 ダイキン工業株式会社 バイモルフ型圧電フィルム
JP2017074792A (ja) 2016-12-28 2017-04-20 日東電工株式会社 透明導電性フィルム及びタッチパネル
JP2019096680A (ja) * 2017-11-21 2019-06-20 日東電工株式会社 圧電フィルムおよび圧電センサ

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP4422380A4

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2024203685A1 (ja) * 2023-03-24 2024-10-03 株式会社クレハ 積層圧電体及びその製造方法
WO2024219145A1 (ja) * 2023-04-19 2024-10-24 株式会社クレハ 積層圧電体及びその製造方法

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