KR100988802B1 - Metal foil for capacitor, solid electrolytic capacitor using the foil and production methods of the foil and the capacitor - Google Patents

Abstract

The metal foil for the capacitor element is produced through a process consisting of etching a metal foil and forming an electrochemically after generating a cutting line in the form of a capacitor element having at least one part of a portion intended as an uninduced anode induction portion. The etching of the foil is preferably performed in the anode induction portion protected by the protective material. The capacitor | condenser element manufactured using the metal foil has a small change in capacity.

Description

Metal foil for capacitors, solid electrolytic capacitors using the foils, and methods for manufacturing the foils and capacitors

The present invention relates to a method for producing a metal foil for capacitors used in various electric appliances, and a capacitor produced using the metal foil. More specifically, the present invention relates to an etching method and an electrochemical forming method of a metal foil for multilayer solid electrolytic capacitors, and a solid electrolytic capacitor using the metal foil produced by the above method.

In accordance with the miniaturization of electronic devices, high-density packaging of printed boards, and the improvement of packaging efficiency, technology development for chip-type or small electronic components is being actively conducted. With the above technology development, there is an increasing demand for the manufacture of chip-type or small electrolytic capacitors used as components thereof. In view of these aspects and ease of handling, the development and dissemination of solid electrolytic capacitors without using an electrolytic solution has increased dramatically in recent years.

Generally, chip-type solid electrolytic capacitors produce an oxide dielectric film on an etched valve-acting metal foil, and form grooves cut in element form on the film (JP-A-5-283304 ("JP- A "refers to" Unexamined Japanese Patent Application "below) or, after fixing the foil cut in the form of an element on a metal support, and producing a solid electrolyte therein, the carbon paste and the silver paste are To prepare a conductive film of a negative electrode comprising, to prepare an outer jacket portion surrounding the whole.

Among valve-acting metals such as aluminum, tantalum, niobium and titanium, aluminum has an oxide film on its surface (electrochemical formation) formed by anodization using aluminum as the anode and its surface portion can be easily enlarged by etching treatment. The advantage of using is that a large capacity capacitor can be produced at a lower cost than other capacitors. Because of this property, aluminum solid electrolytic capacitors are widely used, especially for low voltages.

Recently, electrode foils for aluminum solid electrolytic capacitors are aluminum foils which are electrochemically or chemically etched to increase the surface area, and punched in the form of a pattern of a product to electrochemically form the cut end portions.

As a method of etching aluminum foil, an aluminum foil is used as an anode in an electrolytic solution composed of a chlorine ion-containing aqueous solution to which phosphoric acid, sulfuric acid, nitric acid or the like is added, and a direct current (using an electrode disposed adjacent to the aluminum foil as a cathode) DC) Between the electrodes disposed on both sides of the aluminum foil or aluminum foil and the foil in an electrolytic solution consisting of a direct current electrolytic etching method for etching an aluminum foil by flowing a current and a chlorine-ion containing aqueous solution to which phosphoric acid, sulfuric acid, nitric acid and the like are added. There is an alternating current electrolytic etching method in which an alternating current (AC) current is passed between each electrode disposed on both sides of the electrode.

In direct current electrolytic etching, etching proceeds while forming tunnel-type pits in crystal orientation. In the alternating current electrolytic etching, on the other hand, the etching proceeds while forming etch pits continuously connected like rosaries in a random direction, which makes it possible to enlarge the surface area (area expansion). Thus, although alternating electrolytic etching is mainly performed for etching aluminum foil, a method of combining the above two methods and a method of increasing the alternating voltage stepwise have also been proposed (see JP-A-11-307400). In addition, a method of adjusting the waveform, amplitude, etc. of the alternating current (JP-A-7-235456) to improve the effective area expansion and a method in which aluminum containing a specific metal serving as an initiation point of etching corrosion are used (JP- A-7-169657) is also presented.

After the valve-acting metal foil is made into a porous valve-acting metal foil by electrochemical etching or after a dielectric film is formed on the metal foil, cracks are formed in the porous layer formed by etching near the cut surface, or burrs are cut. It is created at the distal end and roughens the part.

Such cracks, burrs, and the like on the cutting edge surface generated at the time of cutting lower the properties of the condenser.

In the step of adhering the conductive polymer to the foil to create the negative electrode portion, masking is performed on the boundary between the anode-leading-out-part and the negative electrode portion to prevent the treatment solution from seeping into the positive electrode induction portion. However, the conductive polymer easily develops beyond the masking agent into the anode portion, resulting in an increase in leakage current.

WO 02/063645 proposes a method in which an etching film is formed on a cutting edge surface of foil cut in the form of a condenser element by electrolytic etching, in which burrs on the cutting edge portion are dissolved. In this way, however, etching is likely to be localized on the cut end of the foil, which makes it difficult to control the current distribution, and other problems reduce the effective surface area of the device by melting the cut edge portion or rapidly decreasing the strength of the portion. This makes it impossible to carry out the mass-production process of the etched foil with stability.

An object of the present invention is to provide a chemically formed foil and a method for producing the foil in order to produce a capacitor having a small variation in capacity and having a constant shape.

Another object of the present invention is to provide a capacitor element using the foil and a method of manufacturing the capacitor.

The present inventors have completed the present invention on the basis that they have found that the manufacture of metal foil for capacitors with a small variation in capacity can be carried out by a process comprising the following steps: to produce a large amount of capacitor elements at one time. Manufacturing a plurality of cut lines having a predetermined fine width on the valve-acting metal foil material such that the cut portion has an anode form of a condenser element; Etching the surface of the metal foil and the cut edge surface; Performing electrochemical formation

In addition, the inventors found that the etching layer can be formed only at the portion of the cathode portion by protecting the portion to be the anode-inducing portion of the capacitor element with a protective material, thereby adhering the conductive polymer to the cathode portion. In the step of, masking the anode induction part satisfactorily prevents the infiltration of the processing solution, and therefore, it is possible to manufacture a capacitor having a stable capacity and properties of reduced leakage current.

More specifically, the present invention relates to a valve-actuated metal foil for a capacitor, a solid electrolytic capacitor using the foil, and a method for producing the foil and the capacitor.

1) Making a cutting line in the form of a condenser element having at least one part of the valve-actuated metal foil to be an anode-leading-out-part, the cutting edge surface and the valve generated in the previous step A method of producing a metal foil for a capacitor, comprising the step of etching the surface portion of the functional metal foil, and electrochemically forming the metal foil;

2) The method of manufacturing the metal foil for capacitors according to 1 above, wherein etching is performed after protecting the portion to be the anode-inducing part of the capacitor element with a protective material.

3) the method for producing a metal foil for a capacitor according to 2 above, wherein the protective material is removed after etching, and an electrochemical forming step is performed;

4) the method for producing a metal foil for a capacitor according to 2 above, wherein the protective material is removed after electrochemical formation of the etched foil;

5) Masking is applied to the boundary between the anode induction portion and the portion having the solid electrolytic layer formed on the cathode portion before the protective material is removed after etching and electrochemically forming the portion to be the cathode portion. A method for producing a metal foil for capacitors according to 2 above;

6) The manufacturing method of the metal foil for capacitors as described in any one of said 1-3 whose each cut | disconnection site | part is rectangular, U-shaped (horseshoe type), or semicircle which has an uncut site | part;

7) The manufacturing method of the metal foil for capacitors as described in said 1 characterized by the cutting edge surface forming an acute angle of 30 degrees or more with the metal foil surface;

8) The manufacturing method of metal foil for capacitors as described in said 1 characterized by the width d of a cutting line being twice or less of metal foil thickness;

9) A method for producing a metal foil for capacitors as described in 1 above, wherein a plurality of metal foils for capacitors are produced in a single batch process by forming a plurality of cutting lines having a condenser element shape on a single valve-acting metal foil;

10) A method for producing a metal foil for a capacitor according to the above 1, wherein the foil is made of at least one valve-acting metal selected from the group of aluminum, niobium and tantalum;

11) The manufacturing method of the metal foil for capacitors as described in said 1 whose thickness of the said valve | bulb acting metal foil is 0.05-1 mm;

12) The valve-acting metal foil is an aluminum foil containing at least one element selected from the group consisting of Si, Fe, Cu, Zn, Ni, Mn, Ti, Pb, B, P, V and Zr. The manufacturing method of the metal foil for capacitors of 1 description;

13) The method for producing a metal foil for a capacitor according to 12, wherein the total amount of other elements other than the aluminum contained in the foil is from 1 to 1,000 ppm in atomic mass;

14) The manufacturing method of the metal foil for capacitors of said 12 characterized by the said aluminum foil containing 1-100 mass ppm of silicon, 1-100 mass ppm iron, and 1-100 mass ppm copper;

15) The method for producing a metal foil for a capacitor according to 1 above, wherein the etching is an alternating electrolytic etching using at least one waveform selected from the group consisting of a sine wave, a rectangular wave, and a triangle wave;

16) A method for manufacturing the metal foil for capacitors as described in 1 above, wherein the terminal is mounted on the valve-acting metal and the electrodes positioned on both sides of the valve-acting metal, and an alternating current is applied directly to the terminal mounted on the valve-acting metal. ;

17) The manufacturing method of metal foil for capacitors as described in said 1 whose said etching is direct current electrolytic etching;

18) Metal foil for capacitor | condenser produced by the manufacturing method in any one of said 1-17;

19) The metal foil for capacitors according to 18, wherein the edge of the portion to be the cathode has a radius of curvature r of 0.1 to 500 µm;

20) a porous layer formed at the site where the solid electrolyte of the metal foil surface and the cut edge surface is to be formed, wherein the thickness of the porous layer on the cut edge surface, T2 is 1 μm or more, and the thickness of the porous layer on the surface of the metal foil , T1 has the following relationship:

              T2 / T1≤2

It has a metal foil for capacitors as described in said 18 characterized by having;

21) A solid electrolytic capacitor device comprising a solid electrolyte layer and a conductive layer in order on the metal foil according to any one of 18 to 20 above;

22) the solid electrolytic capacitor device according to 21 above, wherein the solid electrolyte layer is made of a conductive polymer;

23) the solid electrolytic capacitor device according to item 22, wherein the monomer forming the conductive polymer is a monomer containing a heterocyclic 5-membered ring or a monomer compound having an aniline skeleton structure;

24) The solid electrolytic capacitor device according to item 23, wherein the heterocyclic 5-membered ring-containing monomer compound is a compound selected from the group consisting of pyrrole, thiophene, furan, polycyclic sulfide and substituted derivatives thereof. ;

25) The solid electrolytic capacitor device according to item 23, wherein the monomer compound containing a heterocyclic 5-membered ring is a compound represented by the following Formula (I):

              (I)

The substituents R ¹ and R ² are each independently a saturated or unsaturated hydrocarbon group having 1 to 10 carbon atoms having a hydrogen atom, linear or side chain, alkoxy group, alkyl ester group, halogen atom, nitro group, cyano group, primary and secondary or tertiary amino group, CF ₃ group, a phenyl group, and shows an top, selected from the group consisting of a substituted phenyl group, the hydrocarbon chains of R ¹ and R ² are together with the carbon atom substituted by R ¹ and R ² 3-, 4-, It may be bonded to each other at any position to form a 5-, 6- or 7-membered saturated or unsaturated hydrocarbon ring structure, and the ring formed may be carbonyl, ether, ester, amide, sulfide, sulfinyl, sulfonyl or already It can optionally contain a furnace bond.

26) The solid electrolytic capacitor device according to the above 23, wherein the monomer compound containing a heterocyclic 5-membered ring is a compound selected from 3,4-ethylenedioxythiophene and 1,3-dihydroisothianaphthene. ;

27) a multilayer solid electrolytic capacitor obtained by laminating a plurality of capacitor elements described in 21 above;

28) manufacturing a cutting line in the form of a condenser element each having at least one portion of the valve-acting metal foil to be an uncut portion of the anode-inducing portion; Etching, cutting the metal foil into respective comb-shaped stripes in which the foil portion cut into the element shape is connected to the anode induction portion, and then electrochemically forming the etched metal foil to produce an oxide dielectric film, the oxide dielectric film layer Forming a solid electrolyte layer on the step, forming a conductive layer on the solid electrolyte layer and the step of cutting the thin flakes in the form of a capacitor element respectively in the anode guide portion of the thin flakes Way.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram which shows the manufacturing process of the metal foil for capacitors of this invention.

FIG. 1A is a state diagram showing a valve-acting metal foil having a plurality of cutting lines in the form of a condenser element for producing a plurality of condenser elements from a single metal foil.

FIG. 1B is a state diagram showing the valve-acting metal foil of FIG. 1A together with the site to be the anode induction portion of the capacitor element protected by the protective material. FIG.

FIG. 1C is a state diagram showing the valve-acting metal foil of FIG. 1B with the protective material removed at the site to be the anode guide portion of the capacitor element after etching the entire foil. FIG.

FIG. 1D is a state diagram showing a portion to be a cathode of an electrochemically generated condenser element after cutting the valve-acting metal foil of FIG. 1C in a comb form. FIG.

2 is an enlarged view of FIG. 1A showing that the valve-actuated metal foil has been cut in the form of a condenser element.

3 is a cross-sectional view taken along the line x-x of FIG. 2.

4 is a cross-sectional view of the solid electrolytic capacitor device of the present invention.

5 is a cross-sectional view of one embodiment of a solid electrolytic capacitor of a multilayer film manufactured from the solid electrolytic capacitor device of the present invention.

The production method of the present invention is as follows.

(1) valve-acting metal

The valve-acting metal foil used in the present invention is a metal foil having a valve action such as aluminum, niobium, tantalum, aluminum alloy, niobium alloy, tantalum alloy. The metal used in the present invention may be in the form of a plate as well as a foil. Preferred examples are foils of aluminum or aluminum alloy, which are commercially available in rolls or plates. The thickness will be sufficient if the aluminum foil is in a range capable of maintaining sufficient strength after etching. The thickness is, for example, 0.05 to 1 mm, preferably 0.08 to 0.4 mm, more preferably 0.1 to 0.2 mm.

Aluminum may contain one or more elements selected from the group consisting of Si, Fe, Cu, Zn, Ni, Mn, Ti, Pb, B, P, V and Zr, and the total amount of these elements is 1 to 1,000 ppm by mass. If it is in a range, Preferably aluminum contains the said foil element in the quantity of 1-100 mass ppm with respect to the total amount of aluminum foil, More preferably, it is the quantity of 10-50 mass ppm.

In particular, aluminum containing 1-100 mass ppm of silicon, 1-100 mass ppm of iron, and 1-100 mass ppm of copper is preferable, and 10-50 mass ppm of silicon, 10-50 mass ppm of iron, 10 Aluminum containing copper of 50 mass ppm is more preferable.

Examples of aluminum alloys composed mainly of aluminum include aluminum alloys having one or more elements of silicon, titanium, zirconium, tantalum, niobium and hafnium.

The size of the original valve-acting metal foil to be cut is not limited as long as it is large enough to produce a plurality of, for example, plate-shaped condenser elements. In particular, the valve-actuated metal foil has a width of 1 to 50 mm, a length of 1 to 50 mm, more preferably a width of 2 to 20 mm, a length of 2 to 20 mm, and even more preferably, each unit of a substrate type element. It is preferable that it is 2-5 mm in width | variety, and has sufficient magnitude | size in the several capacitor element of 2-6 mm in length.

(2) generation of cutting lines

The method of manufacturing the cutting line in the metal foil will be described with reference to the drawings.

In the embodiment shown in Fig. 1A, the cutting line (cutting groove) 5 is produced in the form of a condenser element having a predetermined line width and having one or more portions to be an uninduced anode induction portion, It is created to make a total of 30 (10 lines × 3 lines) in foil (substrate).

As shown in FIG. 2, which is an enlarged view of FIG. 1A, a cutting line (cutting groove) 5 is generated while leaving the portion 2 scheduled to receive anode electricity in the anode induction portion or the final capacitor element in an uncut state. In the above embodiment, the cutting line has a rectangular shape with one side open (uncut), or the corner is an angled or rounded quadrilateral as long as the cutting line can form a condenser element, or U-shaped (horseshoe type), semicircle It can have any form. In FIG. 2, only one cut line appears, but a plurality of cut lines may be created on the valve-actuated metal foil at one time or separately, and the arrangement of the cut lines may be determined as long as the arrangement does not cause problems in subsequent steps. It is not limited to what is shown by).

FIG. 3 is a schematic diagram illustrating a cross section taken along an X-X line in FIG. 2. The width d of the cut line needs to be less than twice the thickness of the foil (if there is a difference in width between the front and back surfaces of the foil, d represents a smaller width). For example, in electrolytic etching, it is important to properly regulate the current because the amount of dissolution of the valve acting metal is mainly affected by the amount of electricity and the shape of the holes and grooves produced in the etching process is significantly affected by the current density. .

In an etching process in which a terminal is mounted on a valve-action metal foil and directly supplies electricity, current flows back and forth between the metal foil and the opposite electrode. Thus, if the foil and the electrode are parallel to each other, the current flows perpendicular to the foil surface and the electrode. However, in the case where the foil has a cutting line, the current does not flow straight vertically but toward the cutting edge or the cutting plane of the cutting line. On the other hand, the current flows through the path of decreasing resistance. That is, the electricity flowing to the electrode portion near the cutting line does not flow to the flat surface of the foil, but flows to the cutting edge or the cutting surface of the cutting line. Thus, the wider the width of the cut line, the more electricity is concentrated at the cut edge to strongly etch the cut edge.

The surface area of the foil is reduced by the width of the cut line created thereon and is increased by the cut surface area. In other words, the narrower the cut line, the less electricity is concentrated in the cut edge and cut surface portion of the cut line, so that the cut edge does not dissolve excessively.

In particular, when the thickness of the foil is t and the width of the cutting line is d, if the cutting edge surface is generated perpendicular to the flat surface portion of the foil, the decrease in the total surface area of the foil is 2d, and the increase is 2t. do. As the increase value "2t" is larger than the decrease value "2d", more current tends to concentrate on the cutting edge. For the purpose of preventing excessive dissolution of the cut edge surface, the reduction value 2d is preferably less than twice the increase value 2t. In other words, 2t × 2 ≧ 2d. In other words, the production of a cutting line having a width d, which is less than or equal to twice the thickness t, contributes to reducing the electrical conversion, thus preventing excessive dissolution of the cutting edge surface.

In general, the metal foil used in the present invention is 1 mm or less, preferably 0.4 mm or less, and more preferably 0.2 mm or less. Therefore, the width of the cut line is 2 mm or less, preferably 0.8 mm or less, and more preferably 0.4 mm or less. If the width exceeds 2 mm, current is concentrated at the cutting edge surface, and the cutting edge surface is locally dissolved, leading to a reduction in the effective area of the device, which in turn reduces the capacity.

Cutting lines are produced by, for example, cutters, Thompson blade cutting, mold punching, or laser cutting. The cutting produces an angle of cut surface and an obtuse angle on either the front surface or the back surface of the foil, while the other surface is angled to produce an angle A of the cutting surface and the acute angle (in the embodiment of FIG. The front surface produces the cut surface and the obtuse angle, while the back surface produces the cut surface and the acute angle). In the present invention, the acute angle A is preferably at least 30 °, more preferably at least 50 °. If the angle is less than 30 °, the etching proceeds at sharp edge sites, which dissolve excessively and as a result the effective area is reduced, resulting in a larger width change in capacity.

(3) etching

In etching the metal foil after the cutting line is formed on the valve-acting metal foil, the etching is performed by immersing the entire metal foil in an electrolytic solution prepared by adding phosphoric acid, sulfuric acid, nitric acid, acetic acid, oxalic acid, etc. to an aqueous solution containing chlorine ions. .

The electrolytic solution used for etching is a solution containing at least chlorine ions, which contains one or more ions including sulfate ions, phosphate ions, acetate ions, oxalate ions, etc., and additionally alkali metal ions or alkalis. Solutions containing earth metal ions can be added.

In the embodiment shown in Fig. 1B, each of the 30 cutting lines 5 each having the form of a condenser element is etched with a single valve-acting metal foil arranged in three lines x 10 lines. It is preferable that the site | part 2 to be an anode guide part for capacitor elements is protected by the protective material 4a. Protection with a protective material can be carried out on both the front and back surfaces of the foil as needed. This protection treatment reduces the proportion of defective products made due to insufficient electrical contact in the manufacture of a multilayer solid electrolytic capacitor composed by stacking a plurality of capacitor elements.

Protective materials that can be used in the etching step can be attached to the valve-acting metal foil close to the material (e.g. aluminum foil) and stably in the area to be protected without reacting with the electrolytic solution (etching solution). As long as it is, any material is possible. Examples of the protective material include acrylic resins, polyethylene sheets, and resist materials. A square rod of the material is inserted in an appropriate area or fixed with a pressure-sensitive adhesive tape or a material that can cover the area. The metal foil to which the protective material was added is immersed in the electrolytic solution and then etched, and then the protective material is removed as shown in Fig. 1C.

The etching is preferably performed by alternating current etching under the condition that the frequency is 1 to 1,000 Hz, the current density is 0.025 to 4 A / cm ² , and the etching electric quantity is 0.02 to 2,000 C / cm ² . It is preferable to increase the current density of the alternating current step by step, and then perform alternating electrolytic etching with a constant current.

In the case of an alternating current, the current has a waveform including any one or more of a waveform, such as a sine wave, a triangle wave, and a rectangular wave.

In addition, DC electrolytic etching and AC electrolytic etching may be used in combination by first performing direct current electrolytic etching and then performing alternating electrolytic etching. Etching may also be performed with direct current electrolytic etching.

Either alternating current, direct current, or a combination thereof may be used in any of the etch modes, and current must be supplied such that the valve-acting metal acts as a counter electrode to an electrode placed on either side of the metal.

It is preferable to mount the terminal to an electrode on both sides of the valve acting metal and the valve-acting metal, and to perform the etching by an alternating current electrolytic etching method in which alternating current is supplied directly between the valve-acting metal and the electrode. In this way the cut surface can also be etched appropriately.

After electrolytic etching, water washing is performed to remove the electrolytic solution components. In particular, in order to reduce the remaining chlorine ions, water washing may be performed after the metal foil is washed with nitric acid solution, sodium aluminate solution, aluminum hydroxide solution and the like. Furthermore, the metal foil can be washed with a solution containing an electrolytic solution used to prepare the dielectric film by anodization.

Further, chemical etching may be applied to enlarge the surface. Nitric acid, iron chloride, or the like may be used for chemical etching.

Therefore, in the resulting metal foil, the cut edge surface has a radius of curvature of 0.1 to 500 µm, preferably 1 to 100 µm, and more preferably 2 to 50 µm. If the radius of curvature is less than 0.1 mu m, the cut edge surface cannot exhibit the effect as a curvature surface, and does not reduce the leakage current.

The thickness T2 of the porous layer on the cut edge produced by etching is preferably equal to or less than twice the thickness T1 of the porous layer on the flat surface of the metal foil. If T2 is more than twice T1, the etching layer on the cut surface decreases in strength, and cracking occurs in the etching layer due to the pressure generated when the capacitor element is stacked or sealed. Fig. 1B shows the case where the protective material 4a is applied to the positive electrode induction part, but when not protected by the protective material, the porous layer also appears on the positive electrode induction part by etching.

(4) electrochemical formation

Subsequently, if the protective material is treated at the time of etching, the protective material is removed as shown in Fig. 1C. Then, the etched valve-actuated metal foil is cut into a comb-shaped foil stripe 10 (comb-shaped aluminum foil stripe) as shown in Fig. 1 (D), and the portion to be the entire stripe or at least the cathode part or the like. The portions 6, which are each intended to have the solid electrolyte produced above, that is, the portions other than the portions to be the anode induction portion 2 shown in FIG. 2, are subjected to the electrochemical forming step. Alternatively, the electrochemical forming step may be performed after removing the protective material and applying masking to the boundary portion between the positive electrode induction part 2 and the site where a solid electrolyte is formed thereon as the negative electrode part in a later step, or It may be done without removing it.

Electrochemical formation can be carried out in a variety of ways, and the conditions necessary for carrying out the electrochemical formation are not particularly limited. For example, electrochemical formation uses an electrolytic solution containing at least one of ions such as oxalic acid, adipic acid, borate, or phosphate, and the concentration of the electrolytic solution is 0.05-20 mass%, and the temperature is 20-20. Up to 90 ° C., the current density is between 0.01 and 600 mA / cm ² and the voltage can be carried out under conditions that are numerically dependent on the electrochemically formed voltage of the treated foil. As for said conditions, electrolyte solution concentration is 0.1-15 mass%, temperature is 40-85 degreeC, and current density is about 0.05-100 mA / cm <^2> .

After electrochemical production, if necessary, for example, it may be immersed in phosphoric acid to improve water resistance, or heat treatment may be performed to reinforce the film.

By the above processing step, the valve-acting metal foil of the present invention is obtained.

(5) masking

Next, a solid electrolyte is formed to become the negative electrode portion. If necessary, masking 4b is added as a pretreatment. Masking can completely insulate the conductive membrane (cathode portion) from the anode portion because it has a function of preventing the treatment solution from seeping into the masked portion in the step of producing the electrolyte membrane and the conductive membrane.

The masking material that can be used is a general heat-resistant resin, preferably a heat-resistant resin that is soluble or swellable in a solvent, a precursor of the resin or an inorganic fine powder and a cellulose resin (see JP-A-11-80596). The composition is used.

Examples of the above include polyphenylsulfone (PPS), polyethersulfone (PES), cyanic acid ester resin, fluoro-resin (tetrafluoroethylene, tetrafluoroethylene / perfluoroalkylvinyl ether copolymer, etc.), low Molecular weight polyimide and derivatives thereof. Among these, polyimide having low molecular weight, polyether sulfone, fluoro resin and its precursor are preferred, and polyimide having low molecular weight is more preferred.

The material is linearly coated with a solution or dispersion solution of an organic solvent, heat-treated, deformed to form a polymer, and then cured.

Masking may be performed by attaching a tape made of polypropylene, polyester, silicon-based resin, fluorine-based resin, or the like, or by forming a resin coating portion.

Masking is applied to the boundary between the anode guide portion 2 and the site 3 where the solid electrolyte 7 is produced.

(6) Formation of Solid Electrolyte

The conductive polymer forming the solid electrolyte used in the solid electrolytic capacitor of the present invention is not limited, but a conductive polymer having a π-electron conjugate structure is preferably used. Examples thereof include a compound having a thiophene skeleton structure as a repeating unit, poly Conductive polymers containing a compound having a cyclic sulfide skeleton, a compound having a pyrrole skeleton, a compound having a furan skeleton or a compound having an aniline skeleton.

Among the monomers used as starting materials for the conductive polymers, examples of the compound having a thiophene skeleton include compounds represented by formula (I).

        (I)

(The substituents R ¹ and R ² are each independently a saturated or unsaturated hydrocarbon group having 1 to 10 carbon atoms having a hydrogen atom, a linear or side chain, an alkoxy group, an alkyl ester group, a halogen atom, a nitro group, a cyano group, and a primary group. , secondary or tertiary amino group, CF _3, phenyl group and substituted phenyl group denotes a work top, selected from the group consisting of the hydrocarbon chain of R ¹ and R ² are R ¹ and R ² together with the carbon atom substituted with a 3-, 4- May be bonded to each other at any position to form a saturated, unsaturated, or hydrocarbon ring structure of 5-, 6 or 7-atoms, and the ring formed may be carbonyl, ether, ester, amide, sulfide, sulfinyl, sulfonyl or May optionally contain imino bonds.)

Specific examples of the compound include 3-methylthiophene, 3-ethylthiophene, 3-propylthiophene, 3-butylthiophene, 3-pentylthiophene, 3-hexylthiophene, 3-heptylthiophene, 3 -Octylthiophene, 3-nonylthiophene, 3-decylthiophene, 3-fluorothiophene, 3-chlorothiophene, 3-bromothiophene, 3-cyanothiophene, 3,4-dimethylthiophene, 3 Derivatives such as, 4-diethylthiophene, 3,4-butylthiophene, 3,4-methylenedioxythiophene and 3,4-ethylenedioxythiophene. Such compounds may be commercially available compounds and may be compounds prepared by known methods of manufacture (eg, the methods described in Synthetic Metal, Vol. 15, page 169 (1986)).

Specific examples of the compound having a polycyclic sulfide skeleton include compounds having a 1,3-dihydropolycyclic sulfide (also called 1,3-dihydrobenzo- [c] thiophene) and Compounds having a 1,3-dihydronaphtho [2,3-c] thiophene framework. In addition, compounds having a 1,3-dihydroanthra [2,3-c] thiophene skeleton and compounds having a 1,3-dihydronaphthaceno [2,3-c] thiophene skeleton may be used. . Such compounds can be prepared by known methods, for example, the method described in JP-A-8-3156.

Further, for example, compounds having a 1,3-dihydronaphtho [1,2-c] thiophene skeleton, 1,3-dihydrophenanthra [2,3-c] thiophene derivative, 1,3 Compounds having a dihydrotriphenylo [2,3-c] thiophene skeleton and 1,3-dihydrobenzo [a] anthraceno [7,8-c] thiophene derivatives may also be used.

In addition, a compound optionally containing nitrogen or a nitrogen-oxide in the condensed ring may be used, and examples of the above include 1,3-dihydrothieno [3,4-b] quinoxaline, 1,3-dihydro Thieno [3,4-b] quinoxaline-4-oxide and 1,3-dihydrothieno [3,4-b] quinoxaline-4,9-dioxide, although the present invention is not so limited. Do not.

Specific examples of the compound having a pyrrole skeleton include 3-methylpyrrole, 3-ethylpyrrole, 3-propylpyrrole, 3-butylpyrrole, 3-pentylpyrrole, 3-hexylpyrrole, 3-heptylpyrrole, 3-octylpyrrole , 3-nonylpyrrole, 3-decylpyrrole, 3-fluoropyrrole, 3-chloropyrrole, 3-bromopyrrole, 3-cyanopyrrole, 3,4-dimethylpyrrole, 3,4-diethylpyrrole, Derivatives such as 3,4-butylenepyrrole, 3,4-methylenedioxypyrrole and 3,4-ethylenedioxypyrrole, although the invention is not so limited. Such compounds may be commercially available compounds and may be prepared by known methods of preparation.

Specific examples of the compound having a furan skeleton include 3-methylfuran, 3-ethylfuran, 3-propylfuran, 3-butylfuran, 3-pentylfuran, 3-hexylfuran, 3-heptylfuran, 3-octylfuran, 3-nonylfuran, 3-decylfuran, 3-fluorofuran, 3-chlorofuran, 3-bromofuran, 3-cyanofuran, 3,4-dimethylfuran, 3,4-diethylfuran, 3, Derivatives such as 4-butylenefuran, 3,4-methylenedioxyfuran and 3,4-ethylenedioxyfuran, although the invention is not so limited. Such compounds may be commercially available compounds or may be prepared by known methods.

Specific examples of compounds having an aniline skeleton include 2-methylaniline, 2-ethylaniline, 2-propylaniline, 2-butylaniline, 2-pentylaniline, 2-hexylaniline, 2-heptylaniline, 2-octylaniline , 2-nonylaniline, 2-decylaniline, 2-fluoroaniline, 2-chloroaniline, 2-bromoaniline, 2-cyanoaniline, 2,5-dimethylaniline, 2,5-diethylaniline, 2 Derivatives such as, 3-butyleneaniline, 2,3-methylenedioxyaniline and 2,3-ethylenedioxyaniline, although the invention is not so limited. Such compounds may be commercially available products or may be prepared by known methods of preparation.

Compounds selected from the group consisting of the compounds described above may also be used in combination to produce a solid electrolyte as a copolymer. In this case, the composition ratio and the polymerizable monomer vary depending on the polymerization conditions and the like, but the preferred composition ratio and the polymerization conditions can be confirmed by a simple test. Examples of methods that can be used for this purpose include the method in which each of the monomers and the oxidizing agent is preferably coated in a solution state in order to separate them, or at the same time to coat a solid electrolyte on the oxide film of the metal foil (JP-A-2 -15611 and JP-A-10-32145 (US Pat. No. 6,124,930).

Generally, in conductive polymers, arylsulfonic acid based dopants such as benzenesulfonic acid, toluenesulfonic acid, naphthalenesulfonic acid, anthracenesulfonic acid or salts of anthraquinonesulfonic acid may be used as the dopant-donating agent.

As shown in FIG. 4, a carbon paste film and a metal powder-containing conductive layer (not shown) are applied to the surface of the solid electrolyte film 7 to form the cathode portion 8 of the capacitor. The metal powder-containing conductive film is tightly bonded with the solid electrolyte layer, serving as an adhesion layer for bonding not only the negative electrode but also the negative electrode induction terminal 9 of the final condenser product (FIG. 5). The thickness of the metal powder-containing conductive layer is not limited, but the thickness is generally about 10 to 100 μm, preferably 10 to 50 μm.

In the case of constituting a multilayer solid electrolyte capacitor using two or more capacitor elements of the present invention, as an embodiment particularly shown in FIG. 5, a plurality of stacked capacitor elements are bonded at the anode guide portion, and the lead frame 11 is bonded. Is coupled to the edge surface of the portion. The lead frame 11 may be sharpened at the edges, ie the edge edges are sharpened, and thus have a slightly flat or rounded shape.

Furthermore, the negative coupling part and the positive electrode coupling part facing the lead frame may serve as the lead terminals 9 and 13.

The material for the lead frame is not particularly limited as long as the material is generally used, but the lead frame may be copper-based (eg, copper-nickel, copper-silver, copper-tin, copper-iron, copper-nickel-silver, Copper-nickel-tin, copper-cobalt-phosphorus, copper-zinc-magnesium, copper-tin-nickel-phosphorus alloy) material or a material having a surface plated with a copper-based material, and when so configured For example, the shape of the lead frame can be devised to reduce the resistance or to obtain sufficient utility to cut the edge groove of the lead frame.

As shown in the cross-sectional view of FIG. 5, the lead terminal 13 is connected to a lead frame 11 coupled to the anode portion 12, and the lead terminal 9 is a solid electrolyte layer 7, a carbon paste layer and a metal. It is bonded to a cathode portion 8 composed of a powder-containing conductive layer, the whole being made of an insulating resin 15 such as an epoxy resin, whereby a solid electrolyte capacitor 14 is obtained.

The invention is described in more detail by reference to representative examples. This is merely a mere example for purposes of explanation and the invention is in no way limited thereto.

Example 1:

Steps to Create a Cut Line

On a 200 μm-thick aluminum foil (containing 20 mass ppm of silicon, 24 mass ppm of iron, 33 mass ppm of copper and 0.9 mass ppm of titanium), a rectangular shape with one side open, each having a width of 200 μm Cut lines were formed. Each of the rectangular shapes in the cut line forming the capacitor element is 3 mm wide and 6 mm long. As shown in Fig. 1A, cutting lines for 30 capacitor elements are arranged in three lines x 10 lines.

Etching steps

Both the front and back surfaces of the site to be the anode induction part were covered with a 1 mm-wide resin tape with a protective material (Fig. 1 (B)), and then the aluminum foil was first coated with an electrolytic solution (10% by mass hydrochloric acid + 0.5% sulfuric acid). It was immersed in 60% of aqueous solution), and it etched by alternating current electrolytic etching on the conditions shown in Table 1.

Electrochemical Formation Step

The resin tape was removed (FIG. 1C), the strips cut into aluminum foil with a comb-like shape with a cutter were immersed in a water-soluble ammonium adipic acid solution and subjected to a voltage of 13 V to form electrochemically non-forming parts electrochemically. Thus, a dielectric film was formed.

Masking steps

Along the surface of the anodic induction part, a masking 4b made of 0.5 mm of resin tape is separated 5 mm from the end of the portion where the solid electrolyte should be formed to control the portion of the solid electrolyte 7 to be formed thereon, the carbon paste and the silver paste. Was added to the site.

Solid electrolyte forming step

Solid electrolyte is produced in the electrochemically formed portion of the membrane as follows. The end of the condenser element of the aluminum foil strip was immersed in an isopropanol solution (solution 1) containing 20% by mass of 3,4-ethylenedioxythiophene, taken out and left at 25 ° C for 5 minutes. Thereafter, at the site treated with the monomer solution, the aluminum foil contained 30% by mass of a water-soluble ammonium persulfate solution prepared so that 2-anthraquinonesulfonate sodium (produced by Tokyo Kasei) had a concentration of 0.07% by mass. It was immersed in an aqueous solution (solution 2), and then dried at 60 ° C. for 10 minutes to perform oxidative polymerization. The procedure of immersion in solution 1 and then immersion in solution 2 was repeated 25 times to perform the oxidative polymerization, thereby forming a solid electrolyte layer. The carbon paste and the silver paste are coated on this solid electrolyte layer. The aluminum foil was cut from the aluminum foil strip and the solid electrolyte capacitor element 8 shown in FIG. 4 was produced.

Fabrication and Testing of Chip-type Multilayer Solid Electrolytic Capacitors

The two solid electrolytic capacitor elements are stacked by combining them on a lead frame made of silver paste, the anode lead terminals are welded to a portion where no conductive polymer is formed, the whole is molded with epoxy resin, and the resulting capacitor element is rated at 120 ° C. A voltage (6.3 V) was applied and left for 2 hours. In this way, a total of 150 chip-type solid capacitors were manufactured.

The resulting multilayer solid electrolytic capacitor was subjected to reflux testing to allow each capacitor to pass through a portion of temperature 230 ° C for 30 minutes, and measured leakage current for 1 minute after applying the rated voltage to 1CV at the rated voltage (6.3V). The average leakage current (kV) of the leakage current having the following measured values was determined. At this time, the leakage current having a measured value of 0.04 CV or more was evaluated as defective. In addition, it was evaluated that the capacity value measured by immersing the capacitor element in the ammonium adipic acid solution (15%) after electrochemical formation has a capacity of 30% or more smaller than the calculated capacity value of the capacitor was evaluated as defective. What was assessed as defective capacity was inspected by disassembly, and as having welding defects having deviations of the anodic electricity removed from the leads, the number of defective units / number of measured units was determined. The generated results are shown in Table 2.

With respect to r and T1 / T2, this value was obtained through the actual measurement on the optical micrograph after polishing the cut surface of the resulting solid electrolytic capacitor. When the foil is cut by punching in the form of a condenser element after the etching treatment, the values r and T2 are because the cutting edge surface is almost perpendicular to the flat surface of the foil, and the cutting edge surface where the core metal of the foil is exposed does not form an etching film. Are all zeros.

Example 2:

The multilayer solid electrolytic capacitor was manufactured in the same manner as in Example 1 except that the thickness of the aluminum foil was changed from 200 µm to 300 µm. The leakage current measurement and the reflux test were performed in the same way. The results obtained are shown in Table 2.

Example 3:

The capacitor was completed in the same manner as in Example 1 except that the portion to be the anode induction part in the etching step was not protected by the resin tape, which is the protective material used in Example 1. This capacitor element was measured in the same manner as in Example 1. The generated results are shown in Table 2.

Example 4:

A condenser was completed in the same manner as in Example 1 except that pyrrole was used in place of 3,4-ethylenedioxythiophene in Example 1. This capacitor element was measured in the same manner as in Example 1. The results obtained are shown in Table 2.

Example 5:

A capacitor was completed in the same manner as in Example 1 except that furan was used in place of 3,4-ethylenedioxythiophene in Example 1. This capacitor element was measured in the same manner as in Example 1. The results obtained are shown in Table 2.

Example 6:

The capacitor was completed in the same manner as in Example 1 except for using the etching current having the triangular waveform instead of the etching current having the sinusoidal waveform. This capacitor element was measured in the same manner as in Example 1. The obtained results are shown in Table 2.

Example 7:

The capacitor was completed in the same manner as in Example 1 except for using an etching current having a rectangular waveform instead of the etching current having a sinusoidal waveform. This capacitor element was measured in the same manner as in Example 1. The obtained results are shown in Table 2.

Comparative Example 1:

Using an aluminum foil having a thickness of 100 μm, etching the foil without cutting lines, cutting the etched foil into pieces having a predetermined size instead of making a cutting line, and then in Example 1 A multilayer solid electrolytic capacitor was prepared in the same manner as in Example 1 except for etching as follows. Leakage current measurements and reflux tests were performed in the same way. The results obtained are shown in Table 2.

Comparative Example 2:

A multilayer film solid electrolytic capacitor was produced in the same manner as in Example 1 except that a cutting line in aluminum foil was generated such that the angle A of the acute angle was 20 °. Measurement of leakage current and reflux test were performed in the same way. The obtained results are shown in Table 2.

Comparative Example 3:

A multilayer film solid electrolytic capacitor was fabricated in the same manner as in Example 1 except that a cutting line in aluminum foil was produced so that the width of the cutting line was 3 mm. Measurement of leakage current and reflux test were performed in the same way. The obtained results are shown in Table 2.

    Waveform  Frequency (Hz) Current density
(A / ㎠) Electricity
(C / ㎠) width
(mm) Acute A
(Degree)   Example 1     sign     30     0.5    400    0.2     90   Example 2     sign     30     0.5    650    0.2     90   Example 3     sign     30     0.5    400    0.2     90   Example 4     sign     30     0.5    400    0.2     90   Example 5     sign     30     0.5    400    0.2     90   Example 6    triangle     30     0.5    400    0.2     90   Example 7   Rectangle     30     0.5    400    0.2     90   Comparative Example 1      -      -      -      -      -     90   Comparative Example 2     sign     30     0.5    400    0.2     20   Comparative Example 3     sign     30     0.5    400    3.0     90

r
(Μm)
T2 / T1 Average capacity
(㎌) Volume
Defective Ratio ^* welding
Defective Ratio ^* Leakage current
Defective Ratio ^* Average
Leakage current
(㎂)   Example 1    52   0.7    63.5    0/150    0/150    0/150    0.15   Example 2    52   0.7    93.2    0/150    0/150    0/150    0.18   Example 3    52   0.7    62.2    3/150    3/150    2/150    0.17   Example 4    52   0.7    63.6    0/150    0/150    0/150    0.15   Example 5    52   0.7    63.5    0/150    0/150    0/150    0.15   Example 6    48   0.6    61.0    0/150    0/150    0/150    0.10   Example 7    47   0.6    62.5    0/150    0/150    0/150    0.14   Comparative Example 1     0   0.0    27.1    5/150    5/150   22/150    1.89   Comparative Example 2    10   0.3    59.0    0/150    0/150    5/150    0.78   Comparative Example 3    89   2.8    50.7    1/150    0/150   10/150    0.95

^* Defective Units / Measured Units

According to the present invention, the following effects are obtained.

(1) By creating a cutting line in a partial form of the condenser element before the etching process, the effective area of the valve-acting metal foil for the condenser element can be produced constantly, so that a porous valve-acting metal having a small change in capacity can be produced. Can be.

The porous layer is also formed on the cut edge surface of the porous valve acting metal at least at the portion where the conductive polymer is formed, and because the sharp edge corner portion of the cut portion is dissolved by etching to form a curved surface, a high capacity capacitor can be produced. And defect generation due to an increase in leakage current after molding and reflux.

(2) Since the porous layer is not formed on the anode-induced portion, and the conductive polymer is not formed on the anode-induced portion by the capillary phenomenon during chemical polymerization, a short circuit due to the formation of the conductive polymer does not occur, Welding becomes easy, and as a result, defects due to reduced welding failures are reduced, and contact resistance is small, so that a capacitor having a small amount of equivalent series of resistances can be produced.

Claims (28)

Making a cutting line in the form of a condenser element having at least one portion of the valve-acting metal foil to be an uncut portion of the anode-inducing portion, etching the cut edge surface and the surface portion of the valve-acting metal foil generated in the previous step, and A method for producing a metal foil for a capacitor, comprising the step of electrochemically forming a metal foil. The method of manufacturing a metal foil for a capacitor according to claim 1, wherein the etching step is performed after protecting a portion to be the anode induction part of the capacitor element with a protective material. The method of manufacturing a metal foil for a capacitor according to claim 2, wherein the protective material is removed after the etching step of the valve-acting metal foil, and an electrochemical forming step is performed. The method of claim 2, wherein the protective material is removed after the electrochemical forming step of the etched foil. 3. A portion according to claim 2, wherein the protective material is removed after the etching step and between the portion having a solid electrolyte layer formed over the portion of the anode-inducing portion and the portion to be the cathode portion before performing the step of electrochemically forming the portion to be the cathode portion. A method for producing a metal foil for capacitors, characterized in that a masking treatment is performed on the boundary line. The method for producing a metal foil for capacitors according to any one of claims 1 to 3, wherein each cut portion is a quadrangular, U-shaped (horseshoe type) or semicircle having an uncut portion. The method of manufacturing a metal foil for a capacitor according to claim 1, wherein the cut edge surface forms an acute angle of 30 ° or more with the metal foil surface. The method of manufacturing a metal foil for a capacitor according to claim 1, wherein the width d of the cut line is not more than twice the thickness of the metal foil. The method of manufacturing a metal foil for capacitors according to claim 1, wherein a plurality of capacitors are generated in a single batch process by forming a plurality of cutting lines in the form of a condenser element on a single valve-acting metal foil. The method of manufacturing a metal foil for a capacitor according to claim 1, wherein the foil is made of at least one valve-acting metal selected from the group of aluminum, niobium and tantalum. The method of manufacturing a metal foil for a capacitor according to claim 1, wherein the valve-acting metal foil has a thickness of 0.05 to 1 mm. The method of claim 1, wherein the valve-acting metal foil is an aluminum foil containing at least one element selected from the group consisting of silicon, iron, copper, zinc, nickel, manganese, titanium, lead, boron, phosphorus, vanadium and zirconium. A method for producing a metal foil for capacitors. The method for producing a metal foil for a capacitor according to claim 12, wherein the total amount of other elements other than aluminum contained in the foil is 1 to 1,000 mass ppm. The said aluminum foil contains 1-100 mass ppm of silicon, 1-100 mass ppm iron, and 1-100 mass ppm copper, The manufacturing method of the metal foil for capacitors of Claim 12 characterized by the above-mentioned. The method of manufacturing a metal foil for capacitors according to claim 1, wherein the etching is an alternating electrolytic etching using at least one waveform selected from the group consisting of sine waves, rectangular waves and triangle waves. 2. The method of claim 1, wherein the etching is an alternating electrolytic etching in which a terminal is mounted to an electrode located on both sides of the valve-acting metal and the valve-acting metal, and an alternating current is applied directly to the terminal mounted to the valve-acting metal. The manufacturing method of the metal foil for capacitors characterized by the above-mentioned. The method for producing a metal foil for capacitors according to claim 1, wherein the etching is direct current electrolytic etching. The metal foil for capacitors obtained by the manufacturing method in any one of Claims 1-5 and Claims 17-17. The metal foil for capacitors according to claim 18, wherein the edge of the cut portion has a radius of curvature r of 0.1 to 500 µm. 19. The metal foil of claim 18, further comprising a porous layer formed at the site where the solid electrolyte is to be formed on the surface of the metal foil and the cut edge surface, respectively, wherein the thickness of the porous layer on the cut edge surface, (T2), is at least 1 µm. The thickness of the porous membrane on the surface of (T1) is the following relationship:               T2 / T1≤2 Metal foil for a capacitor characterized in that it has a. A solid electrolyte layer and a conductive layer are formed in this order on the metal foil of Claim 18, The solid electrolytic capacitor element characterized by the above-mentioned. 22. The solid electrolytic capacitor device according to claim 21, wherein said solid electrolyte layer contains a conductive polymer. 23. The solid electrolytic capacitor device according to claim 22, wherein the monomer forming the conductive polymer is a monomer compound containing a heterocyclic 5-membered ring or a monomer compound having an aniline skeleton. 24. The solid electrolytic capacitor device according to claim 23, wherein the monomer compound containing a heterocyclic 5-membered ring is a compound selected from the group consisting of pyrrole, thiophene, furan, polycyclic sulfide and substituted derivatives thereof. . 24. The solid electrolytic capacitor device according to claim 23, wherein the monomer compound containing a heterocyclic 5-membered ring is a compound represented by the following formula (I).

     (I) (The substituents R ¹ and R ² are each independently a saturated or unsaturated hydrocarbon group having 1 to 10 carbon atoms having a hydrogen atom, linear or side chain, alkoxy group, alkyl ester group, halogen atom, nitro group, cyano group, primary, secondary or tertiary amino group, CF ₃ group, a phenyl group, and shows an top, selected from the group consisting of a substituted phenyl group, the hydrocarbon chains of R ¹ and R ² is 3, 4 together with the carbon atom substituted by R ¹ and R ² May be bonded to each other at any position to form a saturated, unsaturated, or hydrocarbon ring structure of 5-, 6 or 7-atoms, and the ring formed may be carbonyl, ether, ester, amide, sulfide, sulfinyl, sulfonyl or May optionally contain imino bonds.) 24. The solid electrolytic capacitor device according to claim 23, wherein the monomer compound containing a heterocyclic 5-membered ring is a compound selected from 3,4-ethylenedioxythiophene and 1,3-dihydroisothianaphthene. . A multilayer solid electrolytic capacitor obtained by laminating a plurality of capacitor elements according to claim 21 Manufacturing a cutting line in the form of a condenser element, each having at least one portion to be an uncut anodized portion of the valve-actuated metal foil; Cutting the metal foil into comb-shaped stripes in which the foil portion cut into the element shape is connected to the anode induction portion, and then electrochemically forming the etched metal foil to produce an oxide dielectric film, on the oxide dielectric film Forming a solid electrolyte layer on the solid electrolyte layer, forming a conductive layer on the solid electrolyte layer, and cutting the thin flakes in the anode induction portion of the thin flakes, respectively, in the form of a capacitor element. Method for manufacturing an electrolytic capacitor device.

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