WO2010064603A1

WO2010064603A1 - High-dielectric-constant multilayer film

Info

Publication number: WO2010064603A1
Application number: PCT/JP2009/070107
Authority: WO
Inventors: 明天高; 幸治横谷; 麻有子立道; 美晴太田; 恵吏向井; 信之小松
Original assignee: ダイキン工業株式会社
Priority date: 2008-12-01
Filing date: 2009-11-30
Publication date: 2010-06-10
Also published as: JPWO2010064603A1; JP5333456B2

Abstract

Disclosed is a high-dielectric-constant multilayer film comprising: (A) a vinylidene fluoride resin film layer which contains a vinylidene fluoride resin (a) as a film-forming resin; and (B) a layer of an insulating resin (b), which is formed on at least one surface of the vinylidene fluoride resin film layer (A). The high-dielectric-constant multilayer film is characterized in that the vinylidene fluoride resin film layer containing a vinylidene fluoride resin (a) as a film-forming resin has improved electrical insulation and withstand voltage.

Description

Laminated high dielectric film

The present invention relates to a laminated high dielectric film.

In recent years, plastic insulators are characterized by high insulation resistance, excellent frequency characteristics, and excellent flexibility, so they are used for communication, electronic equipment, power, medium / low-pressure phase advance, and inverter. It is expected as a film material such as a film capacitor, a piezoelectric element, a pyroelectric element, and a dielectric for carrying a transfer body.

A film capacitor is usually composed of a film having a structure in which aluminum or zinc is vapor-deposited on the surface of a dielectric resin film, or a film in which an aluminum foil and a dielectric resin film are laminated. A material in which an electrode is formed is also frequently used.

Films for film capacitors are usually formed as a single layer using a dielectric resin as a film-forming resin. As the film-forming resin, fluorine-based polymers such as vinylidene fluoride (VdF) having a high dielectric constant have been studied. Yes.

However, although the VdF resin has a higher dielectric constant than other non-fluorine resins, there are problems in electrical insulation and withstand voltage, and measures for improving them have been proposed (Patent Documents 1 to 3, Non-Patent Documents). Patent Document 1).

Patent Document 1 proposes that electrical insulation is improved by mixing polycarbonate (PC) or thermoplastic polyester (such as PET) with a VdF resin.

Patent Document 2 proposes that the withstand voltage be improved by performing the film formation process of the VdF resin in a clean environment.

In Patent Document 3, an attempt is made to improve the withstand voltage by overlapping a VdF resin film and a polyester film and winding them together.

Non-Patent Document 1 reports that the withstand voltage is improved by stacking a total of 32 layers of PC layers and polyvinylidene fluoride (PVdF) films.

JP-A-56-152103 Japanese Patent Laid-Open No. 5-16209 Japanese translation of PCT publication No. 2002-512443

The inventors of the present invention have studied the prior art, and in the method of mixing PC or PET (Patent Document 1), the VdF resin and PC or PET have low compatibility, so that the mechanical strength is low. In addition to room for improvement, thinning is difficult, and the method to be solved by manufacturing in a clean environment (Patent Document 2) is expensive in terms of equipment and difficult to thin, VdF In the method (Patent Document 3) in which the resin film and the polyester film are overlapped and wound together, the electrical insulation cannot be improved. It became clear that a molding method was required.

The inventors have further researched and found that not only electrical insulation but also withstand voltage is improved by a simple means of providing an insulating resin layer on at least one side of the VdF-based resin film, thereby completing the present invention. It came to do.

That is, the present invention provides (A) a vinylidene fluoride resin film layer containing a vinylidene fluoride resin (a) as a film-forming resin, and (B) provided on at least one surface of the vinylidene fluoride resin film layer (A). The present invention relates to a laminated high dielectric film comprising a layer of insulating resin (b).

The resin (b) constituting the insulating resin layer (B) is preferably a resin having a volume resistivity of 10 ¹³ Ω · cm or more from the viewpoint of excellent effect of improving electrical insulation and withstand voltage.

Specifically, the non-fluorine resin is preferably at least one selected from the group consisting of, for example, a cellulose resin, a polyester resin, a polystyrene resin, a polyolefin resin, and an acrylic resin.

The VdF-based resin (a) constituting the VdF-based resin film layer (A) includes 60 to 100 mol% of vinylidene fluoride units, 0 to 40 mol% of tetrafluoroethylene units, and 0 to 40 mol% of hexafluoropropylene. A polymer is preferred from the viewpoint of high dielectric constant.

In the present invention, the vinylidene fluoride resin film layer (A) is
(C1) high dielectric inorganic particles,
It may contain at least one selected from the group consisting of (c2) a non-fluorinated thermoplastic resin and (c3) rubber particles.

As the high dielectric inorganic particles (c1),
(C1a) Formula (c1a):
M ¹ _a1 N _b1 O _c1
(Wherein M ¹ is a Group 2 metal element; N is a Group 4 metal element; a1 is 0.9 to 1.1; b1 is 0.9 to 1.1; c1 is 2.8 to 3.2. A plurality of M ¹ and N may be present),
(C1b) Formula (c1b):
M ² _a2 M ³ _b2 O _c2
(In the formula, M ² and M ³ are different, M ² is a Group 2 metal element of the periodic table, M ³ is a metal element of the fifth period of the periodic table; a2 is 0.9 to 1.1; 9 to 1.1; c2 is 2.8 to 3.2)
And (c1c) at least selected from the group consisting of complex oxide particles containing at least three metal elements selected from the group consisting of Group 2 metal elements and Group 4 metal elements of the periodic table One is preferable because it is particularly effective for improving the dielectric constant.

As the non-fluorinated thermoplastic resin (c2), at least one selected from the group consisting of a cellulose resin, a polyester resin, a polystyrene resin, a polyolefin resin, and an acrylic resin is preferable because the dielectric loss tangent can be improved.

In the laminated high dielectric film of the present invention, the VdF resin film layer (A) has a thickness of 1 to 30 μm, and the insulating resin layer (B) has a thickness of 0.5 to 5 μm. Is preferable from the viewpoint of good properties and voltage resistance.

The laminated high dielectric film is suitable as a film for a film capacitor.

The present invention also relates to a film capacitor in which an electrode layer is laminated on at least one surface of the laminated high dielectric film of the present invention.

The present invention also provides a laminated high dielectric, characterized in that an insulating resin layer (B) is formed by applying a coating composition containing an insulating resin on at least one surface of a VdF-based resin film layer (A). The present invention also relates to a method for producing a conductive film.

According to the present invention, it is possible to provide a laminated high dielectric film capable of improving the electrical insulation and withstand voltage of a VdF resin film containing a VdF resin (a) as a film forming resin.

The laminated high dielectric film of the present invention is provided on at least one surface of a VdF resin film layer (A) containing a VdF resin (a) as a film-forming resin, and the VdF resin film layer (A). And a layer (B) of insulating resin (b).

Hereinafter, each layer will be described.

(A) VdF-based resin film layer The VdF-based resin layer (A) is a layer containing a VdF-based resin (a) as a film-forming resin, and may be composed of a VdF-based resin alone or a VdF-based resin. In addition to these, various additives and other resins may be contained.

Examples of the VdF resin (a) include VdF homopolymers (PVdF) and copolymers with one or more of other monomers copolymerizable with VdF. Among these, The dielectric constant is 4 or more, more 6 or more, especially 7 or more, especially 7.5 or more, withstand voltage, insulation, improvement in dielectric constant, and high dielectric constant when used as a film. To preferred.

The VdF resin (a) may be a vinylidene fluoride (VdF) homopolymer (PVdF) or a copolymer with another monomer copolymerizable with VdF. Further, it may be a blend of a VdF homopolymer and a VdF copolymer, or a blend of VdF copolymers.

Examples of other monomers copolymerizable with VdF include tetrafluoroethylene (TFE), chlorotrifluoroethylene (CTFE), trifluoroethylene (TrFE), monofluoroethylene, hexafluoropropylene (HFP), Fluorinated olefins such as fluoro (alkyl vinyl ether) (PAVE); fluorinated acrylates, functional group-containing fluorinated monomers, and the like. Of these, TFE, CTFE, and HFP are preferred from the viewpoint of good solvent solubility. As for the copolymerization ratio, it is preferable that VdF is 50 mol% or more, preferably 60 mol% or more from the viewpoint of high dielectric constant and high solvent solubility.

Among them, a polymer containing 60 to 100 mol% of VdF units, 0 to 40 mol% of TFE units and 0 to 40 mol% of HFP is preferable because the relative dielectric constant is 6 or more.

Specifically, VdF homopolymer (PVdF), VdF / TFE copolymer, VdF / TFE / HFP copolymer, VdF / HFP copolymer, VdF / CTFE copolymer, etc. are exemplified. In particular, PVdF, VdF / TFE copolymers, and VdF / HFP copolymers are preferred from the viewpoint of high dielectric constant and good solvent solubility.

In the case of the VdF / TFE copolymer, the composition ratio is such that the VdF unit is 60 to 95 mol% and the TFE unit is 5 to 40 mol%, particularly the VdF unit is 70 to 90 mol% and the TFE unit is A content of 10 to 30 mol% is preferable from the viewpoint of increasing the withstand voltage. In order to reduce the dielectric loss of the VdF resin itself, it is also preferable to copolymerize with ethylene, propylene, alkyl vinyl ether, vinyl acetate, vinyl chloride, vinylidene chloride, CH ₂ = CHCF ₃ , CH ₂ = CFCF ₃ or the like. In this case, since it is difficult to react directly with VdF, it can also be copolymerized with other copolymerizable monomers such as TFE. The relative dielectric constant (1 kHz, 25 ° C.) of the VdF resin itself is preferably 5 or more, preferably 6 or more, and more preferably 7.5 or more from the viewpoint of further increasing the dielectric constant of the film. The upper limit is not particularly limited, but is usually 15 and preferably 13.

In the present invention, the vinylidene fluoride resin film layer (A) is added to the VdF resin (a),
(C1) high dielectric inorganic particles,
It may contain at least one selected from the group consisting of (c2) a non-fluorinated thermoplastic resin and (c3) rubber particles.

The high dielectric inorganic particles (c1) can impart a higher dielectric constant to the VdF resin film layer (A).

The high dielectric inorganic particles (c1) are not particularly limited as long as they are high dielectric inorganic particles, but at least one selected from the group consisting of the following (c1a) to (c1c) is preferable.
(C1a) Formula (c1a):
M ¹ _a1 N _b1 O _C1
(Wherein M ¹ is a Group 2 metal element; N is a Group 4 metal element; a1 is 0.9 to 1.1; b1 is 0.9 to 1.1; c1 is 2.8 to 3.2. A plurality of M ¹ and N may be present, respectively).

Preferred examples of the group 2 metal element M ¹ include Be, Mg, Ca, Sr, Ba, and the like, and examples of the group 4 metal element N include Ti, Zr, and the like.

Specific examples include barium titanate, barium zirconate, calcium titanate, calcium zirconate, strontium titanate, and strontium zirconate. Barium titanate is particularly preferable because of its high dielectric constant.
(C1b) Formula (c1b):
M ² _a2 M ³ _b2 O _c2
(In the formula, M ² and M ³ are different, M ² is a Group 2 metal element of the periodic table, M ³ is a metal element of the fifth period of the periodic table; a2 is 0.9 to 1.1; 9 to 1.1; c2 is 2.8 to 3.2).

As the complex oxide (c1b), specifically, magnesium stannate, calcium stannate, strontium stannate, barium stannate, magnesium antimonate, calcium antimonate, strontium antimonate, barium antimonate, magnesium zirconate, Examples thereof include calcium zirconate, strontium zirconate, barium zirconate, magnesium indium acid, calcium indium acid, strontium indium acid, and barium indium acid.
(C1c) Composite oxide particles containing at least three metal elements selected from the group consisting of Group 2 metal elements and Group 4 metal elements in the periodic table.

In the composite oxide (c1c), specific examples of the Group 2 metal element of the periodic table include Be, Mg, Ca, Sr, Ba, and the like. Specific examples of the Group 4 metal element of the periodic table include, for example, , Ti, Zr, Hf and the like.

Preferred combinations of three or more selected from Group 2 metal elements and Group 4 metal elements of the periodic table include, for example, a combination of Sr, Ba, Ti, a combination of Sr, Ti, Zr, a combination of Sr, Ba, Zr, Ba, Ti, Zr combination, Sr, Ba, Ti, Zr combination, Mg, Ti, Zr combination, Ca, Ti, Zr combination, Ca, Ba, Ti combination, Ca, Ba, Zr combination, Combination of Ca, Ba, Ti, Zr, combination of Ca, Sr, Zr, combination of Ca, Sr, Ti, Zr, combination of Mg, Sr, Zr, combination of Mg, Sr, Ti, Zr, Mg, Ba, A combination of Ti and Zr, a combination of Mg, Ba, and Zr are included.

Specific examples of the composite oxide (c1c) include strontium zirconate titanate, barium zirconate titanate, barium strontium zirconate titanate, magnesium zirconate titanate, calcium zirconate titanate, and barium zirconate titanate. Examples include calcium.

In addition to these composite oxide particles, other composite oxide particles such as lead zirconate titanate, lead antimonate, zinc titanate, lead titanate, and titanium oxide may be used in combination.

The average particle size of the high dielectric inorganic particles (c1) is 2 μm or less, more preferably 1.2 μm or less, particularly about 0.01 to 0.5 μm. From the point which is excellent in it.

The blending amount of the high dielectric inorganic particles (c1) is 10 parts by mass or more, preferably 30 parts by mass or more, particularly preferably 50 parts by mass or more with respect to 100 parts by mass of the VdF resin. If the amount is too small, the effect of improving the dielectric constant of the film becomes small. The upper limit is 500 parts by mass. If the amount is too large, problems occur in terms of strength as a film and surface roughness. A preferable upper limit is 200 parts by mass.

The non-fluorinated thermoplastic resin (c2) can impart properties such as reducing the dielectric loss tangent to the VdF-based resin film layer (A).

As the non-fluorinated thermoplastic resin (c2), at least one selected from a cellulose resin, a polyester resin, a polystyrene resin, a polyolefin resin and an acrylic resin from the viewpoint of high affinity with the VdF resin (a), In particular, at least one selected from the group consisting of cellulosic resins, polyester resins and acrylic resins is preferred.

These non-fluorinated thermoplastic resins (c2) can be mixed within a range that does not impair the high dielectric constant characteristic of the VdF-based resin (a). However, the VdF-based resin (a) / non-fluorinated thermoplastic resin can be mixed. The ratio (mass ratio) of (c2) is 0.1 / 99.9 to 100/0, preferably 20/80 to 100/0, more preferably 30/70 to 100/0, especially 70/30 to 100/0. It is preferable that

As the non-fluorinated thermoplastic resin (c2), a cellulose resin is particularly preferable because it is effective in improving the dielectric constant and reducing the dielectric loss.

Examples of the cellulose-based resin include ester-substituted celluloses such as cellulose monoacetate, cellulose diacetate, cellulose triacetate, and cellulose acetate propionate; and celluloses substituted with ethers such as methylcellulose, ethylcellulose, and hydroxypropylmethylcellulose. Among these, (mono, di, tri) cellulose acetate and methyl cellulose are preferable from the viewpoint of low temperature coefficient of dielectric loss.

The proportion of the cellulose resin in the total mass of the VdF resin (a) and the cellulose resin is 99.9% by mass or less from the viewpoint of high dielectric constant and low dielectric loss, and 80 mass from the viewpoint of good mechanical properties. % Or less is preferable. Further, it is preferably 0.1% by mass or more from the viewpoint of low dielectric loss, good mechanical properties and high dielectric constant, and 2% by mass or more from the viewpoint of low temperature dependence of dielectric loss.

In addition, as the non-fluorinated thermoplastic resin (c2) other than the cellulose resin, for example, polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polyethylene naphthalate (PEN) from the viewpoint of good flexibility and workability. Polyester resins such as polystyrene; poly (styrene-methacrylate) copolymers; polyolefin resins such as polyethylene, polypropylene, and polycycloolefin. In order to further increase the strength, an acrylic resin such as polymethyl methacrylate (PMMA) is preferable. Furthermore, from the viewpoint of good heat resistance, polyphenylene sulfide (PPS), polyphenylene oxide (PPO), polyether ketone (PEK), polyether sulfone (PES) and the like can be mentioned. In addition, in order to improve insulation, polycarbonate (PC), silicone resin, polyvinyl acetate, epoxy resin, polysulfone (PSF), polyethylene oxide (PEO), polypropylene oxide, polyamide (PA), polyimide (PI), polyamideimide ( PAI), polybenzimidazole (PBI), and odd polyamides, cyano pullulans, copper phthalocyanine-based polymers and the like from the viewpoint of supplementing high dielectric properties.

The proportion of the non-fluorinated thermoplastic resin (c2) in the total mass of the non-fluorinated thermoplastic resin (c2) other than the VdF-based resin (a) and the cellulose-based resin is high in dielectric constant and low in dielectric loss. To 99.9% by mass or less, and 80% by mass or less is preferable from the viewpoint of good mechanical properties. Further, it is preferably 0.1% by mass or more from the viewpoint of low dielectric loss, good mechanical properties and high dielectric constant, and 2% by mass or more from the viewpoint of low temperature dependence of dielectric loss.

The rubber particles (c3) have a role of imparting mechanical strength, particularly elongation, to the VdF-based resin film layer (A) and further imparting properties such as rubber elasticity.

Suitable rubber particles for fulfilling such a role include, but are not limited to, acrylic rubber, butadiene rubber, silicone rubber, silicone acrylic composite rubber, natural rubber, nitrile rubber, urethane rubber, styrene-butadiene rubber, isoprene. Examples include diene rubbers such as rubber; fluorine rubbers such as VdF-tetrafluoroethylene (TFE) rubber.

Of these, acrylic rubber, butadiene rubber, and silicone rubber are preferred because of their high relative dielectric constant and good dispersibility.

Also, so-called core-shell rubber particles in which the surfaces of these rubber particles are coated with at least one selected from the group consisting of polymethyl methacrylate and acrylonitrile / styrene copolymer may be used. When the core-shell rubber particles are used, the compatibility with the vinylidene fluoride resin is excellent.

The rubber particles may be uncrosslinked rubber (raw rubber) particles or crosslinked rubber particles, but crosslinked rubber particles are preferred from the viewpoint of good solvent resistance. The rubber may be crosslinked according to a known method.

The particle size of the rubber particles (c3) is about 0.1 to 2.0 μm, more preferably about 0.15 to 1.5 μm, particularly about 0.2 to 1.0 μm in terms of average primary particle size. It is preferable from the viewpoint that both dispersibility and improvement in film strength can be achieved.

The compounding amount of the rubber particles (c3) is 1 part by mass or more, preferably 5 parts by mass or more, particularly preferably 10 parts by mass or more with respect to 100 parts by mass of the VdF resin. If the amount is too small, the effect of improving the mechanical strength, particularly elongation, of the film tends to be small. The upper limit is 30 parts by mass. If the amount is too large, the dispersibility in the resin tends to be poor. A preferable upper limit is 20 parts by mass.

The VdF-based resin film layer (A) used in the present invention contains the VdF-based resin (a) described above (VdF containing the components (c1), (c2), (c3) described above as necessary). It can be formed by a conventionally known melt-kneading method or coating method using a resin-based resin composition, etc., but the coating method (casting method) from the standpoint of simplicity and excellent film homogeneity. ) Is advantageous.

In the coating method, various additives (c1), (c2), (c3) and the like are added to the VdF-based resin (a) as necessary, and dissolved or dispersed in a solvent. A film is produced according to the coating method.

As the coating solvent, any solvent that can dissolve the VdF resin (a) can be used, and a polar organic solvent is particularly preferable. Among these, as the polar organic solvent, for example, ketone solvents, ester solvents, carbonate solvents, cyclic ether solvents, and amide solvents are preferable. Specifically, methyl ethyl ketone, methyl isobutyl ketone, acetone, diethyl ketone, dipropyl ketone, ethyl acetate, methyl acetate, propyl acetate, butyl acetate, ethyl lactate, dimethyl carbonate, diethyl carbonate, dipropyl carbonate, methyl ethyl carbonate, tetrahydrofuran , Methyltetrahydrofuran, dioxane, dimethylformamide, dimethylacetamide and the like are preferable.

As coating methods, knife coating method, cast coating method, roll coating method, gravure coating method, blade coating method, rod coating method, air doctor coating method, curtain coating method, fakunrun coating method, kiss coating method, screen coating Method, spin coating method, spray coating method, extrusion coating method, electrodeposition coating method, etc. can be used, but roll coating is easy because of its ease of operation, small variations in film thickness, and excellent productivity. The method, the gravure coating method and the cast coating method are preferable.

According to the coating method, the VdF resin film (layer) of the present invention is obtained from the viewpoint that a highly uniform composition having a high solubility in the solvent of the VdF resin (a) can be prepared and coating is easy. ) Can be reduced to 30 μm or less, preferably 20 μm or less, further 15 μm or less, and particularly 10 μm or less. The lower limit of the film thickness is 1 μm, preferably about 2 μm, from the viewpoint of maintaining mechanical strength.

In addition, it is preferable to add an affinity improver (d) for the preparation of the coating composition containing the high dielectric inorganic particles (c1). By blending the affinity improver (d), the affinity between the VdF resin (a) and the high dielectric inorganic particles (c1) is increased, and the high dielectric inorganic particles (c1) are converted into the VdF resin (a). And uniformly disperse the high dielectric inorganic particles (c1) and the VdF resin (a) in the film layer (A), thereby suppressing the generation of voids and increasing the dielectric constant. it can.

As the affinity improver (d), a coupling agent (d1), a surfactant (d2) or an epoxy group-containing compound (d3) is effective.

Examples of the coupling agent (d1) include a titanium coupling agent, a silane coupling agent, a zirconium coupling agent, and a zircoaluminate coupling agent.

Examples of the titanium-based coupling agent include monoalkoxy type, chelate type, coordinate type and the like, and monoalkoxy type and chelate type are particularly preferable because of their good affinity with high dielectric inorganic particles (c1). preferable.

Examples of the silane coupling agent include high molecular types and low molecular types, and monoalkoxysilanes, dialkoxysilanes, trialkoxysilanes, dipodal alkoxysilanes, etc. in terms of the number of functional groups. In particular, a low molecular weight alkoxysilane is preferred from the viewpoint of good affinity with the high dielectric inorganic particles (c1).

Examples of the zirconium-based coupling agent include monoalkoxyzirconium and trialkoxyzirconium.

Examples of the zircoaluminate coupling agent include monoalkoxyzircoaluminate and trialkoxyzircoaluminate.

As the surfactant (d2), there are a high molecular type and a low molecular type, and there are a nonionic surfactant, an anionic surfactant and a cationic surfactant from the viewpoint of the type of functional group, and these are used. From the viewpoint of good thermal stability, polymer type surfactants are preferred.

Nonionic surfactants include, for example, polyether derivatives, polyvinylpyrrolidone derivatives, alcohol derivatives and the like. In particular, polyether derivatives are preferred because of their good affinity with the high dielectric inorganic particles (c1). preferable.

Examples of the anionic surfactant include polymers containing sulfonic acid, carboxylic acid, and salts thereof, and in particular, from the viewpoint of good affinity with the VdF resin (a), Is preferably an acrylic acid derivative polymer, a methacrylic acid derivative polymer, or a maleic anhydride copolymer.

Examples of the cationic surfactant include compounds having a nitrogen-containing complex ring such as amine compounds and imidazolines, and halogenated salts thereof, but from the viewpoint of low aggressiveness to the VdF resin (a). A compound having a nitrogen-containing complex ring is preferred. Examples of the salt form include ammonium salts containing halogen anions such as alkyltrimethylammonium chloride. An ammonium salt containing a halogen anion is preferable from the viewpoint of a high dielectric constant.

Examples of the epoxy group-containing compound (d3) include an epoxy compound and a glycidyl compound, which may be a low molecular weight compound or a high molecular weight compound. Among these, a low molecular weight compound having one epoxy group is preferable from the viewpoint of particularly good affinity with the VdF resin (a). In the present invention, an epoxy group-containing coupling agent classified as a coupling agent (for example, epoxysilane) is not included in the epoxy group-containing compound (d3), but is included in the coupling agent (d1).

Preferable examples of the epoxy group-containing compound (d3) are those having the formula (d3): from the viewpoint of excellent affinity with the VdF resin (a).

(Wherein R has a hydrogen atom, an oxygen atom, a nitrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms which may contain a carbon-carbon double bond or a substituent. A good aromatic ring; l is 0 or 1; m is 0 or 1; n is an integer of 0 to 10)
The compound shown by these is mention | raise | lifted.

As a specific example,

And those having a ketone group or an ester group.

The affinity improver (d) can be blended in a range that does not impair the object of the present invention. Specifically, the blending amount is 100 parts by mass of the high dielectric inorganic particles (c1). 0.01 to 30 parts by mass, further 0.1 to 25 parts by mass, particularly 1 to 20 parts by mass can be uniformly dispersed, and are preferable from the viewpoint of high dielectric constant of the obtained film.

In the coating composition used in the present invention, additives such as other reinforcing fillers may be included as optional components within a range not impairing the effects of the present invention.

Examples of reinforcing fillers include silica, silicon carbide, silicon nitride, magnesium oxide, potassium titanate, glass, alumina, and boron compound particles or fibers.

(B) Insulating resin layer In the present invention, the insulating resin layer (B) is provided on at least one surface of the VdF-based resin film layer (A).

This insulating resin layer (B) improves the low electrical insulation, which is a problem of the VdF-based resin film layer (A), and at the same time improves the withstand voltage. The reason is not clear, but the voltage is applied to the relatively thin film due to voltage division. That is, it is estimated that a high voltage is applied to the resin (B) having a high insulating property and the voltage load on (A) is reduced.

When provided on only one side, it is advantageous in terms of improving insulation resistance and maintaining a high dielectric constant, and providing on only one side is advantageous in terms of improving electrical insulation.

The insulating resin (b) constituting the insulating resin layer (B) is a non-fluorine resin having a volume resistivity of 10 ¹³ Ω · cm or more, preferably 10 ¹⁴ Ω · cm or more, particularly 10 ¹⁵ Ω · cm or more. It is preferable from the viewpoint that the effect of improving electrical insulation and withstand voltage is excellent. The upper limit is preferably as high as possible because it is preferable that the electrical insulation is as high as possible (the volume resistivity is large).

From this point, specifically, for example, a cellulose resin, a polyester resin, a polystyrene resin, a polyolefin resin, an acrylic resin, and the like can be given. Specific examples of these resins include those described above for the non-fluorinated thermoplastic resin (c2).

Furthermore, from the viewpoint of good heat resistance, polyphenylene sulfide (PPS), polyphenylene oxide (PPO), polyether ketone (PEK), polyether sulfone (PES), etc., in order to improve insulation, polycarbonate (PC), Silicone resin, polyvinyl acetate, epoxy resin, polysulfone (PSF), polyethylene oxide (PEO), polypropylene oxide, polyamide (PA), polyimide (PI), polyamideimide (PAI), polybenzimidazole (PBI), etc. are also included. .

A particularly preferred specific example is at least one selected from the group consisting of, for example, a cellulose resin, a polyester resin, a polystyrene resin, and an acrylic resin.

The insulating resin layer (B) may be composed only of the insulating resin (b), or may contain other additives.

Examples of other additives include plasticizers, leveling agents, antifoaming agents, antioxidants, antistatic agents, flame retardants, inorganic oxides such as barium titanate, and rubber fine particles. The type and blending amount may be selected within a range that does not impair the effect of improving the insulation and withstand voltage, which are the effects of the present invention.

The insulating resin layer (B) used in the present invention includes the insulating resin (b) described above (including non-fluorinated resin compositions containing other additives described above as necessary). The same can be applied to the VdF resin film layer (A) by a conventionally known melt extrusion method or coating method. It is advantageous to laminate by a coating method (cast method) from the standpoint of simplicity and the resulting laminated high dielectric film being excellent in homogeneity.

In the coating method, a film is prepared according to various coating methods from a coating composition in which other additives are added to the insulating resin (b) as necessary and dissolved or dispersed in a solvent.

As the solvent for forming the insulating resin layer, any solvent that can dissolve the insulating resin (b) can be used. However, when a solvent having an affinity for the VdF resin is used, it has excellent adhesion and durability. Insulating resin layer (B) can be formed.

A preferred organic solvent is a polar organic solvent. Among these, as the polar organic solvent, for example, ketone solvents, ester solvents, carbonate solvents, cyclic ether solvents, and amide solvents are preferable. Specifically, methyl ethyl ketone, methyl isobutyl ketone, acetone, diethyl ketone, dipropyl ketone, ethyl acetate, methyl acetate, propyl acetate, butyl acetate, ethyl lactate, dimethyl carbonate, diethyl carbonate, dipropyl carbonate, methyl ethyl carbonate, tetrahydrofuran , Methyltetrahydrofuran, dioxane, dimethylformamide, dimethylacetamide and the like are preferable.

The thickness of the obtained insulating resin layer (B) is preferably 0.5 μm or more, preferably 0.7 μm or more, and more preferably 1 μm or more from the viewpoint of obtaining good insulation and improved withstand voltage. The upper limit is 5 μm, preferably 3 μm, from the viewpoint of maintaining high dielectric properties.

The laminated high dielectric film of the present invention is useful as a high dielectric film for a film capacitor.

A film capacitor can be produced by laminating an electrode layer on at least one side of the laminated high dielectric film of the present invention. The surface on which the electrode layer is formed may be the insulating resin layer (B), or may be the VdF-based resin film layer (A) when the insulating resin layer is provided only on one side.

As the structure of the film capacitor, for example, a laminated type in which electrode layers and high dielectric films are alternately laminated (Japanese Patent Laid-Open Nos. 63-181411, 3-18113, etc.) or a tape-like high dielectric Winding type in which a body film and an electrode layer are wound (disclosed in Japanese Patent Application Laid-Open No. 60-262414 in which electrodes are not continuously laminated on a high dielectric film, or electrodes on a high dielectric film And the like disclosed in Japanese Patent Laid-Open No. 3-286514, etc.) are continuously laminated. In the case of a wound film capacitor that has a simple structure and is relatively easy to manufacture, and a wound film capacitor in which electrode layers are continuously laminated on a high dielectric film, it is generally a high dielectric that has electrodes laminated on one side. Two films are rolled up so that the electrodes do not come into contact with each other. If necessary, the film is rolled and fixed so as not to be loosened.

The electrode layer is not particularly limited, but is generally a layer made of a conductive metal such as aluminum, zinc, gold, platinum, or copper, and is used as a metal foil or a deposited metal film. In the present invention, either a metal foil or a vapor-deposited metal film, or both may be used in combination. In general, a vapor-deposited metal film is preferable in that the electrode layer can be thinned, and as a result, the capacity can be increased with respect to the volume, the adhesiveness with the dielectric is excellent, and the thickness variation is small. The vapor-deposited metal film is not limited to a single layer. For example, in order to provide moisture resistance, a method of forming an aluminum oxide layer of a semiconductor on an aluminum layer to form an electrode layer (for example, JP-A-2-250306) For example, it may be laminated as necessary. The thickness of the deposited metal film is not particularly limited, but is preferably in the range of 100 to 2000 angstroms, more preferably 200 to 1000 angstroms. When the thickness of the deposited metal film is within this range, the capacity and strength of the capacitor are balanced, which is preferable.

When a deposited metal film is used as the electrode layer, the method for forming the film is not particularly limited, and for example, a vacuum deposition method, a sputtering method, an ion plating method, or the like can be employed. Usually, a vacuum deposition method is used.

Vacuum deposition methods include, for example, the batch method for molded products, the semi-continuous method used for long products, and the air-to-air method. Currently, the semi-continuous method is the mainstay. Has been done. The semi-continuous metal vapor deposition method is a method in which after vapor deposition and winding of a metal in a vacuum system, the vacuum system is returned to the atmospheric system, and the deposited film is taken out.

The semi-continuous method can be specifically performed by the method described in Japanese Patent No. 3664342 with reference to FIG.

When a metal thin film layer is formed on a high dielectric film, the surface of the high dielectric film can be subjected in advance to treatment for improving adhesive properties such as corona treatment or plasma treatment. When a metal foil is used as the electrode layer, the thickness of the metal foil is not particularly limited, but is usually in the range of 0.1 to 100 μm, preferably 1 to 50 μm, more preferably 3 to 15 μm.

The fixing method is not particularly limited, and for example, fixing and protecting the structure may be performed simultaneously by sealing with resin or enclosing in an insulating case. The method for connecting the lead wires is not limited, and examples thereof include welding, ultrasonic pressure welding, heat pressure welding, and fixing with an adhesive tape. A lead wire may be connected to the electrode before it is wound. When encapsulating in an insulating case, if necessary, the opening may be sealed with a thermosetting resin such as urethane resin or epoxy resin to prevent oxidative degradation.

The film capacitor of the present invention thus obtained is highly dielectric, highly insulating, and has a high withstand voltage.

Next, the present invention will be specifically described by way of examples, but the present invention is not limited to such examples.

The characteristic values used in this specification are measured by the following method.

(thickness)
Using a digital length measuring device (MF-1001 manufactured by Sendai Nikon Corporation), the film placed on the substrate is measured at room temperature. The thickness of the insulating resin layer (B) is determined by measuring the total thickness of the final laminated high dielectric film in the same manner and subtracting the thickness of the VdF resin film.

(Dielectric loss and dielectric constant)
Aluminum is vapor-deposited on both sides of the composite film in a vacuum to prepare a sample. Measure the capacitance and dielectric loss tangent of this sample at a frequency of 100 Hz to 10 kHz in a dry air atmosphere at room temperature (20 ° C) and 80 ° C using an LCR meter (ZM2353 manufactured by NF Circuit Design Block Co., Ltd.) To do. The relative dielectric constant and dielectric loss (%) are calculated from the measured values of the obtained capacitances and dielectric loss tangents.

(Electrical insulation)
The volume resistivity (Ω · cm) is measured at room temperature (20 ° C.) at 500 VDC in a dry air atmosphere with a digital superinsulator / microammeter.

(Withstand voltage)
Using a withstand voltage / insulation resistance tester (TOS9201 manufactured by Kikusui Electronics Co., Ltd.), the film placed on the substrate is measured in a dry air atmosphere. The step-up speed is measured at 100 V / s.

Example 1
(Formation of VdF resin film layer (A1))
In a 1 L separable flask, 640 parts by mass of dimethylacetamide (DMAc) (manufactured by Kishida Chemical Co., Ltd.) and polyvinylidene fluoride (PVdF) (KAYNAR761 manufactured by ARKEMA Inc., dielectric constant 9.6 (1 kHz, 25 ° C.)) were 160. A coating composition comprising a PVdF solution having a concentration of 20% by mass was obtained by adding 3 parts by mass and stirring with a three-one motor at 60 ° C. for 3 hours.

Using a microgravure coater (OS-750 manufactured by Yasui Seiki Co., Ltd.), this coating composition was coated on a supporting non-porous polyester (PET) film having a thickness of 38 μm which was subjected to a release treatment. The VdF resin film layer (A1) having a film thickness of 6.2 μm was formed on the supporting PET film by passing through a 6 m drying furnace at 150 ° C. and then a 6 m drying furnace at 180 ° C.

For comparison, the VdF resin film obtained by peeling the VdF resin film layer (A1) from the PET film was subjected to volume resistivity, withstand voltage, and frequencies at 20 ° C. and 80 ° C. (100 Hz, 1 kHz, 10 kHz). The dielectric loss and the relative dielectric constant of were calculated. The results are shown in Table 1 as Comparative Example 1.

(Lamination of insulating resin layer (B1))
In a 1 L separable flask, 680 parts by mass of methyl ethyl ketone (MEK) (manufactured by Kishida Chemical Co., Ltd.) and polyester (byron GK640 manufactured by Toyobo Co., Ltd.), dielectric constant 3.2 (1 kHz, 25 ° C.), volume resistivity 1 × 10 ¹⁸ Ω · cm) was added in 120 parts by mass, and the mixture was stirred with a three-one motor at 60 ° C. for 3 hours to obtain a coating composition for forming an insulating resin layer comprising a polyester solution having a concentration of 15% by mass. .

The coating composition is coated on the VdF resin film layer (A1) on the supporting PET film using a micro gravure coater, and is passed through a 6 m drying oven at 150 ° C. and then a 6 m drying oven at 180 ° C. Thus, a VdF resin film layer (A1) and an insulating resin (polyester) layer (B1) are formed on the PET film, and peeled from the PET film, whereby a VdF resin film layer having a film thickness of 7.3 μm ( A laminated high dielectric film of the present invention comprising A1) / insulating resin (polyester) layer (B1) was obtained. The thickness of the insulating resin (polyester) layer (B1) was 1.1 μm. With respect to the obtained laminated high dielectric film, volume resistivity, withstand voltage, dielectric loss and relative dielectric constant at each frequency (100 Hz, 1 kHz, 10 kHz) at 20 ° C. and 80 ° C. were calculated. The results are shown in Table 1.

Example 2
(Formation of VdF resin film layer (A2))
In a 1 L separable flask, 640 parts by mass of DMAc (manufactured by Kishida Chemical Co., Ltd.) and 160 parts by mass of PVdF were added and stirred with a three-one motor at 60 ° C. for 3 hours to obtain a 20% by mass PVdF solution. .

Separately, 640 parts by mass of DMAc and 160 parts by mass of cellulose acetate (AC) (L-20 manufactured by Daicel Chemical Industries, Ltd.) were placed in a 1 L separable flask and stirred with a three-one motor at 60 ° C. for 3 hours. A 20% strength by weight cellulose acetate solution was obtained.

These two solutions were mixed so that the mass ratio of PVdF and AC was 90/10, and an arbitrary amount of tetrahydrofuran (THF) was added as a diluted solution to produce a coating composition.

This coating composition was cast using a micro gravure coater on a 38 μm-thick supporting PET film that had been subjected to mold release treatment, and then placed in a 6 m drying oven at 150 ° C., followed by a 6 m drying oven at 180 ° C. By passing, a 6.0 μm thick VdF resin film layer (A2) was formed on the supporting PET film.

For comparison, the VdF resin film obtained by peeling the VdF resin film layer (A2) from the PET film was subjected to volume resistivity, withstand voltage, and at each frequency (100 Hz, 1 kHz, 10 kHz) at 20 ° C. and 80 ° C. The dielectric loss and the relative dielectric constant of were calculated. The results are shown in Table 1 as Comparative Example 2.

(Lamination of insulating resin layer (B2))
A polyester (Byron GK640 manufactured by Toyobo Co., Ltd.) layer was laminated on the VdF-based resin film layer (A2) in the same manner as in the method for laminating the insulating resin layer (B1) in Example 1, and then PET for support was used. By peeling from the film, a laminated high dielectric film of the present invention consisting of a 7.2 μm thick VdF resin film layer (A2) / insulating resin (polyester) layer (B2) was obtained. The thickness of the insulating resin layer (B2) was 1.2 μm. About the obtained laminated high dielectric film of the present invention, volume resistivity, withstand voltage, dielectric loss and relative dielectric constant at each frequency (100 Hz, 1 kHz, 10 kHz) at 20 ° C. and 80 ° C. were calculated. The results are shown in Table 1.

Example 3
(Formation of VdF resin film layer (A3))
In a 1 L separable flask, 640 parts by mass of DMAc and 160 parts by mass of PVdF were put, and stirred with a three-one motor at 80 ° C. for 3 hours to obtain a 20% by mass PVdF solution. This PVdF solution was a transparent homogeneous solution.

Separately, 100 parts by mass of barium titanate (BT) having an average particle diameter of 1 μm (BT-4FB manufactured by Nippon Chemical Industry Co., Ltd.) was added to 60 parts by mass of DMAc and 40 parts by mass of methyl isobutyl ketone (MIBK). The same amount of zirconia beads having a diameter of 1 mm was added to this mixture, and the mixture was placed in a desktop planetary ball mill (Planet M manufactured by Gokin Planetaring), and subjected to dispersion treatment at room temperature for 15 minutes at a rotation speed of 800 rpm. The mixture after the dispersion treatment was passed through a stainless steel mesh (80 mesh manufactured by Manabe Kogyo Co., Ltd.) to remove zirconia beads to obtain a composite oxide dispersion solution.

34 parts by mass of this dispersion (containing 17 parts by mass of barium titanate, 10.4 parts by mass of DMAc, 6.4 parts by mass of MIBK) and 50 parts by mass of the PVdF solution (containing 10.0 parts by mass of PVdF and 40.0 parts by mass of DMAc), 26.7 parts by mass of MIBK was mixed to prepare a coating composition.

This coating composition was cast using a micro gravure coater on a 38 μm-thick supporting PET film that had been subjected to mold release treatment, and then placed in a 6 m drying oven at 150 ° C., followed by a 6 m drying oven at 180 ° C. By passing, a VdF resin film layer (A3) having a film thickness of 6.5 μm was formed on the supporting PET film.

For comparison, the VdF resin film obtained by peeling the VdF resin film layer (A3) from the PET film was subjected to volume resistivity, withstand voltage, and frequencies at 20 ° C. and 80 ° C. (100 Hz, 1 kHz, 10 kHz). The dielectric loss and the relative dielectric constant of were calculated. The results are shown in Table 1 as Comparative Example 3.

(Lamination of insulating resin layer (B3))
A polyester (Byron GK640 manufactured by Toyobo Co., Ltd.) layer was laminated on the VdF-based resin film layer (A3) in the same manner as in the method for laminating the insulating resin layer (B1) of Example 1, and then PET for support was used. By peeling from the film, a laminated high dielectric film of the present invention consisting of a 7.5 μm thick VdF resin film layer (A3) / insulating resin (polyester) layer (B3) was obtained. The thickness of the insulating resin layer (B3) was 1.0 μm.

The volume resistivity, withstand voltage, dielectric loss and relative dielectric constant at each frequency (100 Hz, 1 kHz, 10 kHz) at 20 ° C. and 80 ° C. were calculated for the obtained laminated high dielectric film of the present invention. The results are shown in Table 1.

Example 4
Example 3 except that the insulating resin layer (B3) was changed from polyester to cellulose acetate (L-20 manufactured by Daicel Chemical Industries, relative dielectric constant 1.5, volume resistivity 1 × 10 ¹⁵ Ω · cm). In the same procedure, the laminated high dielectric film (film thickness 7.4 μm) of the present invention comprising a VdF resin film layer (film thickness 6.2 μm) / insulating resin (cellulose acetate) layer (film thickness 1.2 μm). ) And various physical properties were measured. The results are shown in Table 1.

Example 5
The same procedure as in Example 3 except that the insulating resin layer (B3) was changed from polyester to polystyrene (Sigma Aldrich Japan, relative dielectric constant 0.1, volume resistivity 1 × 10 ¹⁶ Ω · cm). The laminated high dielectric film (film thickness 7.2 μm) of the present invention consisting of a VdF-based resin film layer (film thickness 6.2 μm) / insulating resin (polystyrene) layer (film thickness 1.0 μm) was prepared. Physical properties were measured. The results are shown in Table 1.

Example 6
In Example 1, the VdF-based resin film layer (A1) was changed from polyvinylidene fluoride (PVdF) to VdF / TFE (VP-50 manufactured by Daikin Industries, Ltd., dielectric constant 9.0 (1 kHz, 25 ° C.)). Except for the change, a laminated high dielectric film of the present invention comprising a VdF resin film layer (A1) / insulating resin (polyester) layer (B1) having a thickness of 7.5 μm was obtained in the same manner. The thickness of the insulating resin (polyester) layer (B1) was 1.3 μm. About the obtained laminated high dielectric film of the present invention, volume resistivity, withstand voltage, dielectric loss and relative dielectric constant at each frequency (100 Hz, 1 kHz, 10 kHz) at 20 ° C. and 80 ° C. were calculated. The results are shown in Table 2.

Example 7
A film thickness of 7 was similarly obtained in Example 1 except that the insulating resin layer (B1) was changed from polyester to methyl methacrylate (Kishida Chemical Co., Ltd., relative permittivity 2.5 (1 kHz, 25 ° C.)). A laminated high dielectric film of the present invention consisting of a VdF resin film layer (A1) / insulating resin (acrylic resin) layer (B1) of 1 μm was obtained. The thickness of the insulating resin (acrylic resin) layer (B1) was 0.9 μm. About the obtained laminated high dielectric film of the present invention, volume resistivity, withstand voltage, dielectric loss and relative dielectric constant at each frequency (100 Hz, 1 kHz, 10 kHz) at 20 ° C. and 80 ° C. were calculated. The results are shown in Table 2.

Example 8
In the same manner as in Example 1, a laminated high dielectric film of the present invention comprising a VdF resin film layer (A1) / insulating resin (polyester) layer (B1) having a film thickness of 4.1 μm was obtained. The thickness of the insulating resin (polyester) layer (B1) was 1.2 μm. About the obtained laminated high dielectric film of the present invention, volume resistivity, withstand voltage, dielectric loss and relative dielectric constant at each frequency (100 Hz, 1 kHz, 10 kHz) at 20 ° C. and 80 ° C. were calculated. The results are shown in Table 2.

Example 9
In the same manner as in Example 1, a laminated high dielectric film of the present invention comprising a VdF resin film layer (A1) / insulating resin (polyester) layer (B1) having a film thickness of 22.2 μm was obtained. The thickness of the insulating resin (polyester) layer (B1) was 2.4 μm. About the obtained laminated high dielectric film of the present invention, volume resistivity, withstand voltage, dielectric loss and relative dielectric constant at each frequency (100 Hz, 1 kHz, 10 kHz) at 20 ° C. and 80 ° C. were calculated. The results are shown in Table 2.

Example 10
In the same manner as in Example 2, except that the cellulose acetate (AC) was changed to a polyester resin (Byron GK640 manufactured by Toyobo Co., Ltd.), a VdF-based resin film layer (A2) having a film thickness of 7.2 μm / insulating property was similarly used. A laminated high dielectric film of the present invention comprising the resin layer (B2) was obtained. The thickness of the insulating resin layer (B2) was 1.0 μm. About the obtained laminated high dielectric film of the present invention, volume resistivity, withstand voltage, dielectric loss and relative dielectric constant at each frequency (100 Hz, 1 kHz, 10 kHz) at 20 ° C. and 80 ° C. were calculated. The results are shown in Table 3.

Example 11
In the same manner as in Example 2, except that cellulose acetate (AC) was changed to acrylic resin (polymethyl methacrylate manufactured by Kishida Chemical Co., Ltd.), a VdF-based resin film layer (A2) / A laminated high dielectric film of the present invention comprising an insulating resin layer (B2) was obtained. The thickness of the insulating resin layer (B2) was 1.0 μm. About the obtained laminated high dielectric film of the present invention, volume resistivity, withstand voltage, dielectric loss and relative dielectric constant at each frequency (100 Hz, 1 kHz, 10 kHz) at 20 ° C. and 80 ° C. were calculated. The results are shown in Table 3.

Example 12
A membrane was prepared in the same manner as in Example 2 except that PVdF and AC were mixed so that the mass ratio thereof was 70/30, and an arbitrary amount of tetrahydrofuran (THF) was added as a diluting solution to produce a coating composition. A laminated high dielectric film of the present invention consisting of a 7.3 μm thick VdF resin film layer (A2) / insulating resin layer (B2) was obtained. The thickness of the insulating resin layer (B2) was 1.2 μm. About the obtained laminated high dielectric film of the present invention, volume resistivity, withstand voltage, dielectric loss and relative dielectric constant at each frequency (100 Hz, 1 kHz, 10 kHz) at 20 ° C. and 80 ° C. were calculated. The results are shown in Table 3.

Example 13
In Example 3, except for mixing so that the mass ratio of PVdF and AC was 90/10, from a VdF-based resin film layer (A2) / insulating resin layer (B2) having a film thickness of 7.0 μm. A laminated high dielectric film of the present invention was obtained. The thickness of the insulating resin layer (B2) was 1.0 μm. About the obtained laminated high dielectric film of the present invention, volume resistivity, withstand voltage, dielectric loss and relative dielectric constant at each frequency (100 Hz, 1 kHz, 10 kHz) at 20 ° C. and 80 ° C. were calculated. The results are shown in Table 3.

Example 14
In Example 3, the high dielectric inorganic particles (c1) were changed from barium titanate (BT) (BT-4FB manufactured by Nippon Chemical Industry Co., Ltd.) to strontium zirconate (manufactured by Kojundo Chemical Laboratory Co., Ltd., average particles). The laminated high dielectric film of the present invention consisting of a 7.5 μm thick VdF resin film layer (A3) / insulating resin (polyester) layer (B3) is obtained in the same manner except that the diameter is changed to 1 μm). It was. The thickness of the insulating resin (polyester) layer (B3) was 1.0 μm. About the obtained laminated high dielectric film of the present invention, volume resistivity, withstand voltage, dielectric loss and relative dielectric constant at each frequency (100 Hz, 1 kHz, 10 kHz) at 20 ° C. and 80 ° C. were calculated. The results are shown in Table 4.

Example 15
In Example 3, the high dielectric inorganic particles (c1) were changed from barium titanate (BT) (BT-4FB manufactured by Nippon Chemical Industry Co., Ltd.) to barium calcium zirconate titanate (BCTZ manufactured by Nippon Chemical Industry Co., Ltd.). In addition, the laminated high dielectric of the present invention comprising a VdF resin film layer (A3) / insulating resin (polyester) layer (B3) having a film thickness of 7.2 μm is the same except that the average particle diameter is changed to 1 μm)) A characteristic film was obtained. The thickness of the insulating resin (polyester) layer (B3) was 1.0 μm. About the obtained laminated high dielectric film of the present invention, volume resistivity, withstand voltage, dielectric loss and relative dielectric constant at each frequency (100 Hz, 1 kHz, 10 kHz) at 20 ° C. and 80 ° C. were calculated. The results are shown in Table 4.

Example 16
In Example 3, the high dielectric inorganic particles (c1) were changed from barium titanate (BT) (BT-4FB manufactured by Nippon Chemical Industry Co., Ltd.) to barium titanate (BTO-100RF manufactured by Toda Kogyo Co., Ltd.) The laminated high dielectric of the present invention comprising a VdF resin film layer (A3) / insulating resin (polyester) layer (B3) having a film thickness of 7.0 μm in the same manner except that the particle diameter is changed to 0.1 μm)) A characteristic film was obtained. The thickness of the insulating resin (polyester) layer (B3) was 0.8 μm. About the obtained laminated high dielectric film of the present invention, volume resistivity, withstand voltage, dielectric loss and relative dielectric constant at each frequency (100 Hz, 1 kHz, 10 kHz) at 20 ° C. and 80 ° C. were calculated. The results are shown in Table 4.

Example 17
In Example 3, 10 parts by mass of the dispersion solution (containing 5 parts by mass of barium titanate, 3 parts by mass of DMAc, 2 parts by mass of MIBK) and 50 parts by mass of the PVdF solution (containing 10.0 parts by mass of PVdF, 40.0 parts by mass of DMAc), MIBK In the same manner, the laminate of the present invention consisting of a VdF-based resin film layer (A3) / insulating resin layer (B3) with a film thickness of 6.8 μm was prepared except that 38.5 parts by mass of was mixed to prepare a coating composition. A type high dielectric film was obtained. The thickness of the insulating resin (polyester) layer (B3) was 0.8 μm. About the obtained laminated high dielectric film of the present invention, volume resistivity, withstand voltage, dielectric loss and relative dielectric constant at each frequency (100 Hz, 1 kHz, 10 kHz) at 20 ° C. and 80 ° C. were calculated. The results are shown in Table 4.

Example 18
In a 1 L separable flask, 640 parts by mass of N, N-dimethylacetamide (DMAc) (manufactured by Kishida Chemical Co., Ltd.) and polyvinylidene fluoride (PVdF) (KAYNAR761 manufactured by ARKEMA), relative permittivity 9.2 (1 kHz, 20 ° C)) 160 parts by mass was added and stirred with a three-one motor at 80 ° C for 3 hours to obtain a PVdF solution having a concentration of 20% by mass. This PVdF solution was a transparent homogeneous solution.

Separately, 18 parts by mass of barium calcium zirconate titanate with an average particle size of 1 μm (BCTZ manufactured by Nippon Chemical Industry Co., Ltd.) is 9 parts by mass of DMAc, 5 parts by mass of methyl isobutyl ketone (MIBK) (manufactured by Kishida Chemical Co., Ltd.), It added to 2 mass parts of PVdF solutions of 20 mass% concentration. The same mass of zirconia beads having a diameter of 1 mm was added to this mixture, and the mixture was placed in a desktop planetary ball mill (Planet M manufactured by Gokin Planetaring), and subjected to a dispersion treatment at room temperature for 5 minutes at a rotation speed of 800 rpm. Next, 2 parts by mass of rubber particles (EXL2313 manufactured by Rohm and Haas Japan Co., Ltd., average primary particle size 0.6 μm) whose core is acrylic rubber and whose shell is polymethyl methacrylate are added, and further rotated. Dispersion treatment was performed at several 800 rpm for 10 minutes. The mixture after the dispersion treatment was passed through a stainless steel mesh (80 mesh manufactured by Manabe Kogyo Co., Ltd.) to remove zirconia beads to obtain a composite oxide dispersion.

A film-forming composition was prepared by mixing 34 parts by mass of this dispersion, 50 parts by mass of the PVdF solution (containing 10 parts by mass of PVdF and 40 parts by mass of DMAc), and 26.7 parts by mass of MIBK.

The composition was cast on a PET film having a thickness of 38 μm using a microgravure coater and passed through a 6 m drying oven at 150 ° C., followed by a 6 m drying oven at 180 ° C. A laminated film in which a cast film having a film thickness of 7.7 μm was formed on the film was obtained. Next, by peeling from the PET film, a film capacitor film of VdF resin having a film thickness of 7.7 μm was obtained.

When the volume resistivity, withstand voltage, tensile elongation at break, dielectric loss and relative dielectric constant at each frequency (100 Hz, 1 kHz, 10 kHz) at 20 ° C. and 80 ° C. were calculated for the obtained film, the volume resistivity ( 20 ° C.) is 5.5 × 10 ¹⁴ Ω · cm, withstand voltage is 250 V / μm, tensile elongation at break is 41%, and relative dielectric constant is 20 (degrees) 28 (100 Hz), 27 (1 kHz), 26 (10 kHz) At 80 ° C., they were 37 (100 Hz), 32 (1 kHz), and 28 (10 kHz). The dielectric loss (%) is 5.5 (100 Hz) at 20 ° C., 2.9 (1 kHz), 2.4 (10 kHz), 7.8 (100 Hz) at 80 ° C., 10.8 (1 kHz), It was 7.4 (10 kHz).

(Measurement of tensile elongation at break)
Using a tensile tester (RTC-1225A manufactured by ORIENTEC Co., Ltd.), the tensile elongation at break (%) is measured.

A coating composition comprising a 15% strength by weight polyester (Byron GK640 manufactured by Toyobo Co., Ltd.) solution was applied to one side of the obtained high dielectric film with a bar coater and dried by hot air at 180 ° C. for 3 minutes for insulation. A conductive resin layer was formed to produce a laminated high dielectric film. The thickness of the insulating resin layer was 1.1 μm. The tensile elongation at break of this film was 45%.

For the obtained laminated high dielectric film, the volume resistivity, withstand voltage, dielectric loss and relative dielectric constant at each frequency (100 Hz, 1 kHz, 10 kHz) at 20 ° C. and 80 ° C. were calculated. The results are shown in Table 4.

Example 19
Electrodes were formed on both surfaces of the high dielectric film produced in Example 1 by depositing aluminum with a target of 3Ω / □ using a vacuum deposition apparatus (VE-2030 manufactured by Vacuum Device Co., Ltd.). A voltage-applying lead wire was attached to these aluminum electrodes to produce stamp-type (for simple evaluation) film capacitors.

Claims

(A) Vinylidene fluoride resin film layer containing vinylidene fluoride resin (a) as a film-forming resin, and (B) insulating property provided on at least one side of the vinylidene fluoride resin film layer (A) A laminated high dielectric film comprising a resin (b) layer.
The laminated high dielectric film according to claim 1, wherein the insulating resin (b) constituting the insulating resin layer (B) is a resin having a volume resistivity of 10 13 Ω · cm or more.
The laminated high dielectric film according to claim 1 or 2, wherein the insulating resin (b) constituting the insulating resin layer (B) is a non-fluorine resin.
The insulating resin (b) constituting the insulating resin layer (B) is at least one selected from the group consisting of a cellulose resin, a polyester resin, a polystyrene resin, a polyolefin resin, and an acrylic resin. The laminated high dielectric film according to any one of the above.
The vinylidene fluoride resin (a) is a polymer containing 60 to 100 mol% of vinylidene fluoride units, 0 to 40 mol% of tetrafluoroethylene units and 0 to 40 mol% of hexafluoropropylene. The laminated high dielectric film according to any one of the above.
The vinylidene fluoride resin film layer (A) is
(C1) high dielectric inorganic particles,
6. The laminated high dielectric film according to claim 1, comprising at least one selected from the group consisting of (c2) a non-fluorinated thermoplastic resin and (c3) rubber particles.
High dielectric inorganic particles (c1)
(C1a) Formula (c1a):
M 1 a1 N b1 O C1
(Wherein M 1 is a Group 2 metal element; N is a Group 4 metal element; a1 is 0.9 to 1.1; b1 is 0.9 to 1.1; c1 is 2.8 to 3.2. A plurality of M 1 and N may be present),
(C1b) Formula (c1b):
M 2 a2 M 3 b2 O c2
(In the formula, M 2 and M 3 are different, M 2 is a Group 2 metal element of the periodic table, M 3 is a metal element of the fifth period of the periodic table; a2 is 0.9 to 1.1; 9 to 1.1; c2 is 2.8 to 3.2)
And (c1c) at least selected from the group consisting of complex oxide particles containing at least three metal elements selected from the group consisting of Group 2 metal elements and Group 4 metal elements of the periodic table The laminated high dielectric film according to claim 6, which is one type.
The laminated high dielectric constant according to claim 6 or 7, wherein the non-fluorinated thermoplastic resin (c2) is at least one selected from the group consisting of a cellulose resin, a polyester resin, a polystyrene resin, a polyolefin resin, and an acrylic resin. Sex film.
The laminate according to any one of claims 1 to 8, wherein the vinylidene fluoride resin film layer (A) has a thickness of 1 to 30 µm, and the insulating resin layer (B) has a thickness of 0.5 to 5 µm. Type high dielectric film.
The laminated high dielectric film according to any one of claims 1 to 9, which is used for a film capacitor.
A film capacitor in which an electrode layer is laminated on at least one surface of the laminated high dielectric film according to any one of claims 1 to 10.
A laminated high dielectric film characterized in that an insulating resin layer (B) is formed by applying a coating composition containing an insulating resin to at least one surface of a vinylidene fluoride resin film layer (A). Production method.