JP4392313B2 - SOLID ELECTROLYTIC CAPACITOR ELECTRODE MEMBER, ITS MANUFACTURING METHOD, AND SOLID ELECTROLYTIC CAPACITOR USING SOLID ELECTROLYTIC CAPACITOR ELECTRODE MEMBER - Google Patents

Description

  TECHNICAL FIELD The present invention relates to an electrode member for a solid electrolytic capacitor, a method for producing the same, and a solid electrolytic capacitor using the electrode member for a solid electrolytic capacitor. The present invention relates to an electrode member for a solid electrolytic capacitor using a molecule as a solid electrolyte, a manufacturing method thereof, and a solid electrolytic capacitor using the electrode member for a solid electrolytic capacitor.

  In general, it is strongly desired that an electrolytic capacitor used for a secondary circuit portion of a power supply circuit, a circuit portion around a CPU of a personal computer, and the like be small and have a high capacity. Further, this type of electrolytic capacitor is required to have a low ESR (equivalent series resistance) corresponding to a high frequency. In order to realize this low ESR, a solid electrolytic capacitor using a functional polymer having high conductivity as a solid electrolyte has been developed and put into practical use, and the demand for the polymer solid electrolytic capacitor is increasing.

  The conventional solid electrolytic capacitor is configured so that the surface area of the electrode can be increased in order to increase the capacity. As a structure of the solid electrolytic capacitor for realizing this, a cylindrical type in which a series of electrodes are rotated and a laminated type in which a number of electrodes are laminated are adopted.

  For example, in Japanese Patent Application Laid-Open No. 59-108311 (Patent Document 1), a plurality of foil-like aluminum sheets having a surface area enlarged by etching formed in a predetermined shape are laminated as a structure of a laminated solid electrolytic capacitor electrode. In addition, an aluminum foil laminate is formed by pressure bonding, and a plurality of grooves that penetrate from the upper surface to the lower surface are formed in the aluminum foil laminate.

  In a cylindrical solid electrolytic capacitor, an aluminum plate or aluminum foil or an aluminum etched plate or aluminum etched foil provided with a dielectric layer is used as an anode, and an aluminum foil or aluminum etched foil is used as a cathode conductor. Yes. In a multilayer solid electrolytic capacitor, an aluminum plate or aluminum foil or an aluminum etched plate or aluminum etched foil provided with a dielectric layer is used as an anode, and a graphite paste layer or a silver paste layer is used as a cathode conductor. Yes.

  It is the electrolyte layer that substantially acts as a cathode. As a material for this electrolyte layer, a functional polymer having high conductivity is used in order to achieve low ESR in a solid electrolytic capacitor. For example, conductive polymer compounds selected from the group consisting of polypyrrole, polyaniline, polythiophene, polyfuran, and dielectrics thereof, in particular, polypyrrole, polyaniline, polyethylenedioxythiophene, and the like are used for the purpose of reducing ESR.

  However, aluminum foil and aluminum etched foil used as a cathode conductor in a cylindrical solid electrolytic capacitor have a robust oxide film formed on the surface, so that the resistance value at the interface with the electrolyte layer (surface resistance) Value). This increase in the surface resistance value has been an obstacle to achieving low ESR in a cylindrical solid electrolytic capacitor.

  On the other hand, in order to realize miniaturization and high capacity, it is necessary to increase the surface area per unit projected area of the anode and cathode conductors in the solid electrolytic capacitor.

  For example, in order to realize a reduction in size and an increase in capacity, Japanese Patent Application Laid-Open No. 2002-367867 (Patent Document 2) is made of a valve action metal foil made of tantalum, niobium, or aluminum having a purity of 99% or more. There has been proposed an electrode member for a solid electrolytic capacitor comprising an anode body and an electrode layer made of a valve metal powder formed on the anode body.

  Further, in order to realize a reduction in size and an increase in capacity, Japanese Patent Laid-Open No. 2003-272958 (Patent Document 3) discloses a low melting point valve action metal foil made of niobium foil and a higher melting point than this valve action metal foil. There has been proposed an electrode member for a solid electrolytic capacitor comprising an electrode layer formed on the valve action metal foil using a powder of a valve action metal made of tantalum or an alloy thereof.

However, these electrode members do not have sufficient adhesion between the anode body and the electrode layer, and there is a limit in expanding the surface area per unit projected area. There wasn't.
JP 59-108311 A JP 2002-367867 A JP 2003-272958 A

  Accordingly, an object of the present invention is to solve the above-mentioned problems, and to provide an electrode member for a solid electrolytic capacitor that has a low surface resistance value and can achieve low ESR.

  Another object of the present invention is to provide an electrode member for a solid electrolytic capacitor in which the surface area per unit projected area of the electrode can be increased and the capacity can be increased.

  Furthermore, another object of the present invention is to provide a method of manufacturing an electrode member for a solid electrolytic capacitor that can achieve low ESR and high capacity.

  Still another object of the present invention is to provide a solid electrolytic capacitor using an electrode member for a solid electrolytic capacitor that can achieve low ESR and high capacity.

  As a result of intensive studies to solve the problems of the prior art, the present inventors have achieved solid electrolyte capacitors that can achieve the above-mentioned object by heating under specific conditions after adhering a carbon-containing material to aluminum. It has been found that an electrode member can be obtained. The present invention has been made based on such knowledge of the inventors.

  An electrode member for a solid electrolytic capacitor according to the present invention includes aluminum and a carbon-containing layer formed on the surface of the aluminum, and an aluminum element and carbon formed between the aluminum and the carbon-containing layer. An intervening layer containing an element is further provided.

  In this solid electrolytic capacitor electrode member, the intervening layer formed between the aluminum and the carbon-containing layer acts to enhance the adhesion between the aluminum and the carbon-containing layer. Therefore, the resistance does not increase inside the electrode member, and the reduction in ESR is not hindered. In addition, the carbon-containing layer acts to increase or increase the surface area of aluminum. Therefore, it is possible to achieve downsizing and high capacity of the solid electrolytic capacitor using the electrode member of the present invention.

  In the electrode member for a solid electrolytic capacitor of the present invention, the intervening layer constitutes a first surface portion including aluminum carbide formed in at least a part of the surface of the aluminum. The carbon-containing layer constitutes a second surface portion formed so as to extend outward from the first surface portion.

  In such a configuration, the second surface portion acts to increase the surface area of the aluminum. Moreover, since the 1st surface part containing the carbide | carbonized_material of aluminum is formed between aluminum and the 2nd surface part, this 1st part is the 2nd surface part which increases the surface area of aluminum, and It works to increase the adhesion between the two. Thereby, in the electrode member for solid electrolytic capacitors, improvement in adhesion of the carbon-containing layer and increase in surface area can be achieved more effectively.

  Furthermore, in the electrode member for a solid electrolytic capacitor according to the present invention, the carbon-containing layer further includes carbon particles, and the second surface portion is formed between the first surface portion and the carbon particles and includes aluminum carbide.

  In such a configuration, even when a thick carbon-containing layer is formed, the adhesion between the carbon-containing layer and aluminum can be reliably maintained.

  In the electrode member for a solid electrolytic capacitor of the present invention configured as described above, since the carbon-containing layer is present on the surface of aluminum instead of the oxide film, the solid electrolytic capacitor can be reduced without increasing the surface resistance value. ESR can be achieved.

  In the electrode member for a solid electrolytic capacitor according to the present invention, the carbon-containing layer includes aluminum particles in addition to the carbon particles, and is formed in at least a partial region of the surface of the aluminum particles and includes aluminum carbide surface portions. And an aluminum particle outer portion that is formed so as to extend from the surface portion of the aluminum particle toward the outside of the surface of the aluminum particle and contains an aluminum carbide. In this case, even if a thicker carbon-containing layer is formed, adhesion within the carbon-containing layer can be improved and peeling can be prevented.

  In the electrode member for a solid electrolytic capacitor according to the present invention, preferably, the carbon-containing layer includes an inclusion containing an aluminum element and a carbon element therein.

  When the carbon-containing layer is thin, the adhesion between aluminum and the carbon-containing layer can be improved as compared with the conventional case only by the presence of the intervening layer. However, when the carbon-containing layer is thick, peeling may occur inside the carbon-containing layer. In this case, by forming inclusions containing an aluminum element and a carbon element inside the carbon-containing layer, adhesion within the carbon-containing layer can be improved, and peeling can be prevented.

  The inclusion is preferably a compound of an aluminum element and a carbon element. The carbon-containing layer is preferably a compound of an aluminum element and a carbon element.

  In the electrode member for a solid electrolytic capacitor of the present invention, the carbon-containing layer is preferably formed so as to extend outward from the surface of aluminum. In this case, the carbon-containing layer exhibits the effect of expanding or increasing the surface area of aluminum more effectively.

  In the electrode member for a solid electrolytic capacitor of the present invention, the thickness of aluminum is preferably 5 μm or more and 1 mm or less.

  In the electrode member for a solid electrolytic capacitor of the present invention, the carbon-containing layer may be formed on at least one surface of aluminum, and the thickness is preferably 0.01 μm or more and 5 mm or less.

  A solid electrolytic capacitor according to the present invention includes an electrode member for a solid electrolytic capacitor having any of the above-described characteristics. Thereby, low ESR and high capacity of the solid electrolytic capacitor can be achieved.

  The method of manufacturing an electrode member for a solid electrolytic capacitor according to the present invention includes a step of attaching a carbon-containing material to the surface of aluminum, and placing the aluminum containing the carbon-containing material on the surface in a space containing the hydrocarbon-containing material. And heating in a heated state.

  In the manufacturing method of the present invention, the surface of aluminum can be covered with the carbon-containing layer by a simple process of attaching the carbon-containing material to the surface of aluminum and heating the aluminum in a space containing the hydrocarbon-containing material. Instead, an intervening layer containing an aluminum element and a carbon element can be formed between the aluminum and the carbon-containing material layer. Thereby, the adhesiveness between aluminum and a carbon containing layer can be improved.

  As described above, according to the electrode member for a solid electrolytic capacitor of the present invention, the surface resistance value can be reduced and the capacity of the solid electrolytic capacitor can be increased. Moreover, if a solid electrolytic capacitor is comprised using the electrode member for solid electrolytic capacitors of this invention, low ESR and high capacity | capacitance can be achieved.

  As shown in FIG. 1, according to one embodiment of the present invention, according to the cross-sectional structure of the electrode member for a solid electrolytic capacitor, a carbon-containing layer 2 is formed on the surface of aluminum (aluminum plate or aluminum foil) 1. Yes. An intervening layer 3 containing an aluminum element and a carbon element is formed between the aluminum 1 and the carbon-containing layer 2. The carbon-containing layer 2 is formed so as to extend outward from the surface of the aluminum 1. The intervening layer 3 constitutes a first surface portion including an aluminum carbide formed in at least a part of the surface of the aluminum 1. The carbon-containing layer 2 includes a second surface portion 21 formed so as to extend outward from the first surface portion 3 in the form of a fiber or a filament. The second surface portion 21 is a compound of an aluminum element and a carbon element. The carbon-containing layer 2 further includes a large number of carbon particles 22. The second surface portion 21 extends outward from the first surface portion 3 in the form of a fiber or filament, and is formed between the first surface portion 3 and the carbon particles 22 and contains aluminum carbide.

  Further, as shown in FIG. 2, as another embodiment of the present invention, the cross-sectional structure of the electrode member for a solid electrolytic capacitor has the same structure as the cross-sectional structure shown in FIG. Further included are carbon particles 22 and aluminum particles 23. The second surface portion 21 extends outward from the first surface portion 3 in the form of a fiber or a filament, and is formed between the first surface portion 3 and the carbon particles 22 and contains aluminum carbide. Furthermore, the aluminum particle surface portion 24 is formed in at least a partial region of the surface of the aluminum particle 23 and contains aluminum carbide. The aluminum particle outer portion 25 is formed so as to extend from the aluminum particle surface portion 24 toward the outside of the surface of the aluminum particle 23 in a cactus-like form, and contains aluminum carbide.

  The electrode member for a solid electrolytic capacitor of the present invention is suitably used for either an anode or a cathode conductor.

  In the electrode member for a solid electrolytic capacitor of the present invention, the carbon-containing layer may be formed on at least one surface of aluminum, and the thickness is preferably in the range of 0.01 μm to 5 mm. In particular, the foil is preferably within the range of 1 μm to 5 mm in the case of the anode, and within the range of 0.5 μm to 300 μm in the case of the cathode conductor.

  The solid electrolytic capacitor electrode member of the present invention is preferably an electrode member for a solid polymer electrolytic capacitor using aluminum as a base material and a functional polymer having high conductivity as a solid electrolyte.

  In one embodiment or another embodiment of the present invention, aluminum as a substrate on which the carbon-containing layer is formed is not particularly limited, and pure aluminum or an aluminum alloy can be used. Aluminum used in the present invention is composed of lead (Pb), silicon (Si), iron (Fe), copper (Cu), manganese (Mn), magnesium (Mg), chromium (Cr), zinc (Zn). ), Titanium (Ti), vanadium (V), gallium (Ga), nickel (Ni) and boron (B) at least one alloy element added within the necessary range, or the above inevitable impurities Also includes aluminum with limited elemental content.

  Although the thickness of aluminum is not specifically limited, It is preferable to exist in the range of 5 micrometers or more and 1 mm or less. In particular, in the electrode member for a solid electrolytic capacitor of the present invention, it is preferable that the anode is within a range of 20 μm to 1 mm, and the cathode conductor is within a range of 5 μm to 200 μm.

  As the above-mentioned aluminum, those produced by a known method can be used. For example, a molten aluminum or aluminum alloy having the above predetermined composition is prepared, and an ingot obtained by casting this is appropriately homogenized. Thereafter, aluminum can be obtained by subjecting the ingot to hot rolling and cold rolling. In addition, you may perform an intermediate annealing process in the range of 150 degreeC or more and 400 degrees C or less in the middle of said cold rolling process.

  In one embodiment of the method for producing an electrode member for a solid electrolytic capacitor of the present invention, the type of the hydrocarbon-containing substance used is not particularly limited. The types of hydrocarbon-containing substances include, for example, paraffinic hydrocarbons such as methane, ethane, propane, n-butane, isobutane and pentane, olefinic hydrocarbons such as ethylene, propylene, butene and butadiene, and acetylenes such as acetylene. Examples thereof include hydrocarbons and derivatives of these hydrocarbons. Among these hydrocarbons, paraffinic hydrocarbons such as methane, ethane, and propane are preferable because they become gaseous in the process of heating aluminum. More preferred is any one of methane, ethane and propane. The most preferred hydrocarbon is methane.

  The hydrocarbon-containing substance may be used in any state such as liquid or gas in the production method of the present invention. The hydrocarbon-containing material may be present in a space where aluminum is present, and may be introduced into the space where aluminum is disposed by any method. For example, when the hydrocarbon-containing substance is in a gaseous state (methane, ethane, propane, etc.), the hydrocarbon-containing substance may be filled alone or together with an inert gas in a sealed space where aluminum is heat-treated. Further, when the hydrocarbon-containing substance is a liquid, the hydrocarbon-containing substance may be filled alone or together with an inert gas so as to be vaporized in the sealed space.

  In the step of heating aluminum, the pressure of the heating atmosphere is not particularly limited, and may be normal pressure, reduced pressure, or increased pressure. Further, the pressure adjustment may be performed at any time during the temperature rise to a certain heating temperature or during the temperature lowering from the certain heating temperature while the pressure is maintained at a certain heating temperature.

  The weight ratio of the hydrocarbon-containing substance introduced into the space for heating aluminum is not particularly limited, but is usually in the range of 0.1 to 50 parts by weight in terms of carbon with respect to 100 parts by weight of aluminum. It is preferable to make it within a range of 0.5 parts by weight or more and 30 parts by weight or less.

  In the step of heating aluminum, the heating temperature may be appropriately set according to the composition of aluminum that is the object to be heated, etc., but is preferably within the range of 450 ° C. or higher and lower than 660 ° C. It is more preferable to carry out within the range. However, in the production method of the present invention, heating aluminum at a temperature lower than 450 ° C. is not excluded, and aluminum may be heated at a temperature exceeding at least 300 ° C.

  Although the heating time depends on the heating temperature and the like, it is generally in the range of 1 hour to 100 hours.

  When the heating temperature is 400 ° C. or higher, the oxygen concentration in the heating atmosphere is preferably 1.0% by volume or lower. When the heating temperature is 400 ° C. or higher and the oxygen concentration in the heating atmosphere exceeds 1.0% by volume, the thermal oxide film on the surface of aluminum is enlarged, and the surface resistance value of aluminum may be increased.

  Further, the surface of aluminum may be roughened before the heat treatment. The surface roughening method is not particularly limited, and known techniques such as cleaning, etching, blasting and the like can be used.

  In the production method of the present invention, after a carbon-containing material is attached to the surface of aluminum, or when a thick carbon-containing layer is formed, after a carbon-containing material and aluminum powder are attached, a space containing a hydrocarbon-containing material. The step of heating aluminum is employed. In this case, the carbon-containing substance attached to the surface of aluminum may be any of activated carbon fiber, activated carbon cloth, activated carbon felt, activated carbon powder, black ink, carbon black, or graphite. Moreover, carbon compounds, such as silicon carbide, can also be used conveniently. For the attachment method, the above-mentioned carbon-containing material prepared in a slurry, liquid, or solid form using a binder, solvent, water, or the like is attached on the surface of aluminum by coating, dipping, or thermocompression bonding. Just do it. After depositing the carbon-containing substance on the surface of aluminum, it may be dried at a temperature in the range of 20 ° C. or more and 300 ° C. or less before the heat treatment.

  In the production method of the present invention, the carbon-containing material may contain aluminum powder. Further, the carbon-containing material may contain a ferroelectric or a high dielectric constant oxide for the purpose of increasing the capacity of the solid electrolytic capacitor.

  In the production method of the present invention, when a binder is used to adhere a carbon-containing substance to the surface of aluminum, the binder is a carboxy-modified polyolefin resin, a vinyl acetate resin, a vinyl chloride resin, a vinyl chloride copolymer resin, Vinyl alcohol resin, vinyl fluoride resin, acrylic resin, polyester resin, urethane resin, epoxy resin, urea resin, phenol resin, acrylonitrile resin, nitrocellulose resin, paraffin wax, polyethylene wax and other synthetic resins, wax or tar, and glue Natural resin such as urushi, pine resin, beeswax or wax can be preferably used. These binders include those that volatilize when heated, depending on the molecular weight and the resin type, and those that remain in the carbon-containing layer as a carbon precursor by thermal decomposition. The binder may be diluted with an organic solvent or the like to adjust the viscosity.

  In the production method of the present invention, in order to form a thick carbon-containing layer, when the carbon-containing substance and the aluminum powder are adhered to the surface of aluminum, 0.01 part by weight with respect to 100 parts by weight of the carbon-containing substance. It is preferable to add the aluminum powder at a weight ratio in the range of 10000 parts by weight or less.

  The method for manufacturing an electrode member for a solid electrolytic capacitor according to the present invention includes a step of attaching a carbon-containing material to the surface of aluminum and heating the aluminum in a space containing the hydrocarbon-containing material, and then cooling the aluminum. And a reheating step, that is, an activation treatment step.

  In this case, the step of cooling and reheating aluminum is preferably performed in a temperature range of 100 ° C. or higher and lower than 660 ° C.

  Solid electrolytic capacitor electrode members (cathode conductors) were prepared according to the following conventional examples 1 and 2 and examples 1 to 10. For comparison with the examples, a reference example of the carbon-coated aluminum foil was also prepared.

(Conventional example 1)
An aluminum hard foil (JIS A1050-H18) having a thickness of 30 μm was heated in air at a temperature of 300 ° C. for 12 hours to produce an electrode member for a solid electrolytic capacitor. The nominal purity of the aluminum foil was 99.55% by mass, and the mass spectrometric values of the composition were 2250 ppm for silicon and 3800 ppm for iron.

(Conventional example 2)
AC etching for 50 seconds under conditions of a temperature of 50 ° C. and a current density of 0.5 A / cm ^{2 in} an electrolytic solution containing 15% hydrochloric acid and 0.5% sulfuric acid on an aluminum soft foil (JIS A1080-O) having a thickness of 50 μm After the treatment, the etched aluminum foil was washed with water and dried to produce a solid electrolytic capacitor electrode member.

(Examples 1 to 10)
A carbon-containing substance was applied to both surfaces of a 30 μm thick aluminum hard foil (JIS A1050-H18), and was adhered by drying at a temperature of 100 ° C. for 10 minutes. The composition of the carbon-containing material is obtained by adding 1 part by weight of an acrylic resin having an average molecular weight of 3000 and 1 part by weight of aluminum powder having an average particle diameter of 1 μm to 1 part by weight of carbon black having an average particle diameter of 0.05 μm as shown in Table 1. Was dispersed in toluene to a solid content of 30%. The adhesion of the carbon-containing material was set so that the thickness after drying became the value shown in Table 1 on one side of the aluminum foil.

  Thereafter, the aluminum foil to which the carbon-containing material was adhered was heated for 12 hours under the conditions of the atmosphere and temperature shown in Table 1 to produce a solid electrolytic capacitor electrode member.

(Reference example)
A carbon-containing substance was applied to both surfaces of a 30 μm thick aluminum hard foil (JIS A1050-H18), and was adhered by drying at a temperature of 100 ° C. for 10 minutes. The composition of the carbon-containing substance was obtained by adding 1 part by weight of polytetrafluoroethylene (PTFE) to 1 part by weight of carbon black (# 2400B manufactured by Mitsubishi Chemical Corporation). The carbon-containing substance was adhered such that the thickness after drying was 2 μm on one side of the aluminum foil.

  Thereafter, the aluminum foil to which the carbon-containing material was adhered was heated for 12 hours under the conditions of the atmosphere and temperature shown in Table 1 to produce a carbon-coated aluminum foil.

  The carbon-coated aluminum foil thus obtained corresponds to the heating atmosphere changed in Example 6.

  A solid electrolytic capacitor electrode member (anode) was produced according to the following Conventional Example 3 and Examples 11-14.

(Conventional example 3)
After subjecting an aluminum soft foil having a thickness of 100 μm to an AC etching process for 100 seconds in an electrolyte containing 12% hydrochloric acid and 0.6% phosphoric acid at a temperature of 40 ° C. and a current density of 0.5 A / cm ^2. And converted to 3 V in a 150 g / L ammonium adipate aqueous solution at 60 ° C. Then, the formed aluminum foil was washed with water and dried to produce a solid electrolytic capacitor electrode member. The nominal purity of the aluminum foil was 99.99 mass%, and the mass analysis values of the composition were 15 ppm for silicon, 16 ppm for iron, and 39 ppm for copper.

(Examples 11-14)
A carbon-containing substance was applied to both surfaces of a 30 μm thick aluminum hard foil (JIS A1050-H18), and was adhered by drying at a temperature of 100 ° C. for 10 minutes. The composition of the hydrocarbon carbon-containing material is 1 part by weight of an acrylic resin having an average molecular weight of 3000 and 1 part by weight of aluminum powder having an average particle diameter of 1 μm per 1 part by weight of carbon black having an average particle diameter of 0.05 μm. Was dispersed in toluene to a solid content of 50%. The adhesion of the carbon-containing material was set so that the thickness after drying became the value shown in Table 2 on one side of the aluminum foil.

  Thereafter, the aluminum foil to which the carbon-containing material was adhered was heated for 12 hours under the conditions of the atmosphere and temperature shown in Table 2, and then converted to 3 V in a 150 g / L ammonium adipate aqueous solution at 60 ° C. The formed aluminum foil was washed with water and dried to produce an electrode member for a solid electrolytic capacitor.

  In the electrode members for solid electrolytic capacitors (or carbon-coated aluminum foil) obtained in Conventional Examples 1 to 3, Examples 1 to 14 and Reference Examples, capacitance, surface resistance value, adhesion between the carbon-containing layer and aluminum Evaluated. The evaluation conditions are as follows. The evaluation results are shown in Tables 1 and 2.

[Capacitance]
The capacitance of each sample was determined according to the capacitance measurement method described in Section 7.4 of JEITA (Electronic Information Technology Industry Association) Standard RC-2364A “Test Method for Electrode Foil for Aluminum Electrolytic Capacitors”. Measured in aqueous ammonium or ammonium borate solution.

[Surface resistance value]
The surface resistance characteristics were evaluated by the AC impedance method.

  Each sample was immersed in a 1M hydrochloric acid aqueous solution having a liquid temperature of 20 ° C., and the AC impedance was measured under a constant current. The measurement frequency was 20 points from 0.5 to 1000 Hz. Generally, the simplest equivalent circuit at the electrode / aqueous solution interface is represented by a circuit in which a solution resistance is connected in series to a parallel circuit of a charge transfer resistance and an electric double layer capacitance. Therefore, the AC impedance measurement value measured under this condition is displayed as a vector on the complex plane, and the X axis is represented by a real part and the Y axis is represented by an imaginary part. Furthermore, in the AC impedance trajectory of each sample obtained by the above method, the value of the intersection with the X axis was adopted as the surface resistance value.

[Adhesion]
Adhesion was evaluated by a taping method. In a sample of a solid electrolytic capacitor electrode member having a width of 10 mm and a length of 100 mm, a pressure-sensitive adhesive tape having a bonding surface having a width of 15 mm and a length of 120 mm on the surface of the carbon-containing layer (product name “Scotch tape” manufactured by Sumitomo 3M Limited) ”), The adhesive tape was peeled off, and the adhesion was evaluated according to the following formula.

  Adhesion (%) = {weight of the carbon-containing layer after peeling (mg) / weight of the carbon-containing layer before peeling (mg)} × 100

表１と表２の結果から、実施例１〜１４の固体電解コンデンサ用電極部材は、従来例１〜３の固体電解コンデンサ用電極部材、参考例の炭素被覆アルミニウム箔に比べて、高い静電容量を示すとともに、低い表面抵抗値と高い密着性を示すことがわかる。すなわち、実施例１〜１４の固体電解コンデンサ用電極部材は、表面抵抗値を減少させるとともに、固体電解コンデンサの容量を増大させることができ、本発明の固体電解コンデンサ用電極部材を用いて固体電解コンデンサを構成すれば、低ＥＳＲ化と高容量化を達成することができることがわかる。

From the results of Tables 1 and 2, the electrode members for solid electrolytic capacitors of Examples 1 to 14 are higher in electrostatic capacity than the electrode members for solid electrolytic capacitors of Conventional Examples 1 to 3 and the carbon-coated aluminum foil of Reference Example. It can be seen that the capacitor exhibits a low surface resistance and high adhesion as well as a capacitance. That is, the electrode members for solid electrolytic capacitors of Examples 1 to 14 can reduce the surface resistance value and increase the capacity of the solid electrolytic capacitors, and solid electrolytic using the electrode members for solid electrolytic capacitors of the present invention. It can be seen that a low ESR and a high capacity can be achieved by configuring a capacitor.

  It should be considered that the embodiments and examples disclosed above are illustrative and non-restrictive in every respect. The scope of the present invention is shown not by the above embodiments and examples but by the scope of claims, and includes all modifications and variations within the scope and meaning equivalent to the scope of claims.

  By configuring the solid electrolytic capacitor using the electrode member for a solid electrolytic capacitor according to the present invention, low ESR and high capacity can be achieved.

It is a figure which shows typically the cross-sectional structure of the electrode member for solid electrolytic capacitors as one embodiment of this invention. It is a figure which shows typically the cross-sectional structure of the electrode member for solid electrolytic capacitors as another embodiment of this invention.

Explanation of symbols

  1: Aluminum, 2: Carbon-containing layer, 3: Intervening layer (first surface portion), 21: Second surface portion, 22: Carbon particles, 23: Aluminum particles, 24: Aluminum particle surface portion, 25: Aluminum Particle outer part.

Claims (10)

With aluminum,
A carbon-containing layer formed on the surface of the aluminum;
An intervening layer formed between the aluminum and the carbon-containing layer and containing an aluminum element and a carbon element;
The intervening layer includes a first surface portion including an aluminum carbide formed in at least a partial region of the aluminum surface;
The carbon-containing layer includes a second surface portion formed to extend outward from the first surface portion;
The electrode member for a solid electrolytic capacitor, wherein the carbon-containing layer further includes carbon particles, and the second surface portion is formed between the first surface portion and the carbon particles and contains an aluminum carbide.   The carbon-containing layer is formed of aluminum particles, an aluminum particle surface portion containing aluminum carbide formed in at least a part of the surface of the aluminum particles, and from the aluminum particle surface portion to the outside of the surface of the aluminum particles. The electrode member for a solid electrolytic capacitor according to claim 1, further comprising an aluminum particle outer portion formed so as to extend toward the surface and containing an aluminum carbide.   The electrode member for a solid electrolytic capacitor according to claim 1, wherein the carbon-containing layer includes an inclusion containing an aluminum element and a carbon element.   The electrode member for a solid electrolytic capacitor according to any one of claims 1 to 3, wherein the inclusion is a compound of an aluminum element and a carbon element.   The electrode member for a solid electrolytic capacitor according to any one of claims 1 to 4, wherein the carbon-containing layer is a compound of an aluminum element and a carbon element.   The electrode member for a solid electrolytic capacitor according to any one of claims 1 to 5, wherein the carbon-containing layer is formed to extend outward from the surface of the aluminum.   The thickness of the said aluminum is an electrode member for solid electrolytic capacitors of any one of Claim 1- Claim 6 which is 5 micrometers or more and 1 mm or less.   8. The electrode member for a solid electrolytic capacitor according to claim 1, wherein a thickness of the carbon-containing layer formed on one surface of the aluminum is 0.01 μm or more and 5 mm or less.   The solid electrolytic capacitor using the electrode member for solid electrolytic capacitors of any one of Claim 1- Claim 8. Attaching a carbon-containing material to the surface of the aluminum;
And heating the aluminum with the carbon-containing material attached to the surface in a state of being disposed in a space containing the hydrocarbon-containing material.

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