JP2007134475A - Solid electrolytic capacitor, and method of manufacturing same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solid electrolytic capacitor which prevents a characteristic change caused by intruding of damp or oxygen from an external air through a packing resin, and to provide a method of manufacturing the same. <P>SOLUTION: A barrier layer 12 is formed on a packing resin of a capacitor body 11 via an intermediate member 13 in order to prevent damp or oxygen of an external air from its intruding. The barrier layer 12 is composed of a metal layer and/or an inorganic layer formed by a vapor-phase growth method, or a metal foil formed by a rolling method. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a solid electrolytic capacitor used in various electronic devices and vehicle circuits and a method for manufacturing the same.

  With recent downsizing, weight reduction, and digitization of electronic devices, the solid electrolytic capacitors used there are also small and light, such as an increase in equivalent series resistance (hereinafter referred to as ERS) and an increase in leakage current. There is little demand for deterioration of characteristics and there is an increasing demand for stable products.

  As shown in the sectional view of FIG. 9, the conventional solid electrolytic capacitor 45 is connected to a plurality of capacitor elements 41 laminated so as to connect the cathode layers 40 to each other, to each anode lead portion 36 and to the cathode layer 40. The anode terminal 42 and the cathode terminal 43, and a part of the anode terminal 42 and the cathode terminal 43 and the exterior resin 44 having an insulating property for covering the capacitor element 41 are included.

  As shown in the sectional view of FIG. 10, the capacitor element 41 is divided into a plate-like anode body 35 made of a valve metal, an insulator layer 37 for separating the surface of the anode body 35, and the anode body 35. An anode lead portion 36 as one end, a dielectric oxide film 38 formed on the surface of the other end, a solid electrolyte layer 39 made of a conductive polymer sequentially formed on the dielectric oxide film 38, The cathode layer 40 is comprised.

  Changes in characteristics such as the infiltration of moisture from the outside through the exterior resin 44 of the solid electrolytic capacitor 45 reduces the conductivity of the conductive polymer used for the solid electrolyte layer 39 and increases the ESR of the solid electrolytic capacitor 45. Occurs.

  As a conventional technique for preventing moisture from entering from the outside, there is known a technique in which a barrier layer made of metal is provided on almost the entire surface of the exterior resin 44, and this barrier layer is formed by electroless plating (see Patent Document 1). ).

Similarly, as a conventional technique for preventing moisture from entering from the outside, a technique in which a barrier layer made of a fluorine polymer layer is formed on almost the entire surface of the exterior resin 44 is known (see Patent Document 2).
JP 63-087721 A Japanese Utility Model Publication No. 64-54320

  However, in the conventional solid electrolytic capacitor 45 described above, in the case of Patent Document 1, the electrolytic solution component and moisture used for plating in the electroless plating layer forming step enter through the exterior resin 44, and the initial characteristics of the solid electrolytic capacitor 45. There was a problem of deteriorating the material.

  Further, in the case of Patent Document 2, if the fluorine-based polymer layer is formed thin in order to reduce the size and thickness of the solid electrolytic capacitor 45, unevenness in the thickness of the fluorine-based polymer layer is likely to occur, and the portion where the fluorine-based polymer layer is thin Therefore, there is a problem in that the moisture is infiltrated through the exterior resin 44 and the characteristics of the solid electrolytic capacitor 45 are deteriorated.

  Furthermore, since the conductive polymer used for the solid electrolyte layer 39 also reacts with oxygen, it is necessary to prevent oxygen from entering from the outside.

  An object of the present invention is to solve such a conventional problem and to provide a solid electrolytic capacitor having stable characteristics while preventing moisture and oxygen from entering from the outside.

  In order to solve the above-mentioned problems, the present invention provides a barrier layer made of a metal layer and / or an inorganic layer on an exterior resin so as to prevent moisture and oxygen from entering from the outside. Thus, a solid electrolytic capacitor is formed.

  In addition, the barrier layer which consists of metal foil may be provided on exterior resin, and this metal foil may be formed by a rolling method.

  According to the structure of this solid electrolytic capacitor, a barrier layer made of a metal layer and / or an inorganic material layer is provided on the exterior resin, and the metal layer and / or the inorganic material layer is formed by a vapor phase growth method. Even if the barrier layer is thin, the metal layer and / or inorganic layer has a dense structure, so that moisture and oxygen shielding from the outside can be improved. Thus, it is possible to provide a solid electrolytic capacitor having stable characteristics.

  In addition, the same effect is acquired also in what provides the barrier layer which consists of metal foil on exterior resin, and forms this metal foil by a rolling method.

  In the solid electrolytic capacitor of the present invention, a barrier layer composed of a metal layer and / or an inorganic layer is provided on an exterior resin, and the metal layer and / or the inorganic layer is formed by a vapor phase growth method. The solid electrolytic capacitor is configured such that an intermediate material is interposed therebetween.

  According to this configuration, moisture and oxygen can be prevented from entering from the outside by the barrier layer provided on the exterior resin, and the characteristics of the solid electrolytic capacitor can be stabilized.

  Furthermore, by providing a protective layer on the barrier layer, it is possible to prevent changes in capacitor characteristics due to damage to the metal layer and / or the inorganic layer.

  As a method of forming a barrier layer composed of a metal layer and / or an inorganic layer on the exterior resin, a step of forming a protective layer serving as a first layer on a support substrate, a metal layer serving as a second layer, and / Or a step of forming an inorganic layer on the first layer by vapor deposition, and an intermediate material to be the third layer is formed on the second layer to form a three-layer laminate. The process of forming on top and the process of transferring the laminate onto the exterior resin of the solid electrolytic capacitor are sequentially performed.

  The intermediate material only needs to be a resin having an action of closely bonding and fixing the exterior resin and the metal layer and / or the layer made of an inorganic material. For example, a polyester resin, an acrylic resin, a polypropylene resin, an epoxy resin, A phenol resin, a polyamide resin, or a polyimide resin can be used. When the thickness of the intermediate material is less than 0.5 μm, the adhesiveness with the exterior resin becomes insufficient, which is not preferable, and when it is thicker than 30 μm, the adhesiveness is not improved, so 0.5-30 μm is preferable. More preferably, it is 1-10 micrometers.

  The metal layer is made of a metal such as aluminum, nickel, copper, or silver, and an alloy in which these metals are combined may be used. The thickness of the metal layer is preferably 10 to 500 nm. When the thickness is less than 10 nm, moisture and oxygen shielding properties are low, and when the thickness is greater than 500 nm, cracks are likely to occur during formation of the metal layer, which is not preferable.

  The inorganic layer is made of an inorganic material such as aluminum oxide, silicon oxide, indium oxide, tin oxide, or zirconium oxide, and these inorganic materials may be combined. The thickness of the inorganic layer is preferably 10 to 150 nm. If the thickness is smaller than 10 nm, the moisture and oxygen shielding properties are low, and if it is larger than 150 nm, cracks are likely to occur during the formation of the inorganic layer.

  Furthermore, the layer composed of a metal layer and an inorganic substance may be used in combination with a metal such as aluminum, nickel, copper, or silver, and an inorganic substance such as aluminum oxide, silicon oxide, indium oxide, tin oxide, or zirconium oxide. .

  Further, the protective layer formed on the metal layer and / or the inorganic layer may be composed of, for example, a polyester resin, an acrylic resin, a urethane resin, an epoxy resin, a polyamide resin, a polyimide resin, or the like, such as aluminum oxide or silicon oxide. It may be composed of an inorganic material. Moreover, you may provide the resin layer which has the effect | action which improves the adhesiveness with a metal layer and / or an inorganic layer in this protective layer.

  Vapor deposition methods include physical vapor deposition (PVD) such as vacuum deposition, sputtering, and ion plating, or reactive vacuum deposition, reactive ion sputtering, and reactive ion plating. A conventionally well-known technique of chemical growth (CVD) can be used, and thereby a remarkable effect is obtained that a uniform thin film layer that hardly permeates moisture and oxygen can be obtained.

  Note that a metal layer and / or a layer made of an inorganic material may be formed directly on the exterior resin so as not to short-circuit the anode terminal and the cathode terminal by vapor deposition.

  In the solid electrolytic capacitor of the present invention, a barrier layer made of a metal foil is provided on the exterior resin, the metal foil is formed by a rolling method, and an intermediate material is interposed between the exterior resin and the barrier layer. The solid electrolytic capacitor is configured.

  According to this configuration, moisture and oxygen can be prevented from entering from the outside by the barrier layer provided on the exterior resin, and the characteristics of the solid electrolytic capacitor can be stabilized.

  Furthermore, by providing a protective layer on the barrier layer, it is possible to prevent changes in capacitor characteristics due to damage to the metal foil.

  In addition, as a method of forming a barrier layer made of a metal foil on the exterior resin, a metal formed by a step of forming a protective layer serving as a first layer on a support substrate and a rolling method serving as a second layer A step of laminating the foil on the first layer, a step of forming a laminate composed of three layers on the support substrate by forming an intermediate material to be the third layer on the second layer, and The process of transferring a laminated body on the exterior resin of a solid electrolytic capacitor is performed sequentially.

  The intermediate material only needs to be a resin having a function of closely fixing the exterior resin and the metal foil. For example, polyester resin, acrylic resin, polypropylene resin, epoxy resin, phenol resin, polyamide resin, polyimide Resin can be used. When the thickness of the intermediate material is less than 0.5 μm, the adhesiveness with the exterior resin becomes insufficient, which is not preferable, and when it is thicker than 30 μm, the adhesiveness is not improved, so 0.5-30 μm is preferable. More preferably, it is 1-10 micrometers.

  The metal foil is made of a metal such as aluminum, nickel, copper, or silver, and an alloy in which these metals are combined may be used. The thickness of the metal foil is preferably 0.5 to 30 μm, more preferably 0.5 to 10 μm. If the thickness is smaller than 0.5 μm, it is difficult to handle, and if it is larger than 30 μm, the thickness of the capacitor is increased. Absent.

  Furthermore, the protective layer formed on the metal foil may be made of, for example, a polyester resin, an acrylic resin, a urethane resin, an epoxy resin, a polyamide resin, a polyimide resin, or the like, and is made of an inorganic material such as aluminum oxide or silicon oxide. May be. Moreover, you may provide the resin layer which has the effect | action which improves the adhesiveness with metal foil in this protective layer.

  In addition, a barrier layer may be provided on substantially the entire surface of the exterior resin of the solid electrolytic capacitor, but at least the solid electrolyte layer of the capacitor element is interposed between the cathode terminal connection portion and the barrier layer. The formation area can be reduced.

  Next, specific embodiments will be described, but the present invention is not limited to these embodiments.

(Embodiment 1)
As shown in the cross-sectional view of FIG. 1, the solid electrolytic capacitor 14 of the present invention fixes a capacitor body 11, a barrier layer 12 provided on the upper surface of the capacitor body 11, and the barrier layer 12 and the capacitor body 11. And an intermediate member 13 for the purpose.

  The capacitor body 11 is formed by laminating a plurality of capacitor elements 7 to connect the cathode layers 6 to each other, to connect the anode terminal 8 to the anode lead portion 2, and to connect the cathode layer 6 to the cathode terminal 9; A part of the anode terminal 8 and the cathode terminal 9 and the capacitor element 7 are covered with the insulating exterior resin 10.

  As shown in FIG. 2, the capacitor element 7 includes a flat plate-like anode body 1 that is a valve metal, and an insulator for dividing the surface of the anode body 1 into an anode lead portion 2 and a dielectric oxide film 4. The layer 3, the solid electrolyte layer 5 made of polypyrrole, and the cathode layer 6 are sequentially formed on the dielectric oxide film 4.

  As shown in FIG. 3, the barrier layer 12 is formed by sequentially laminating an inorganic layer 15 made of aluminum oxide and a protective layer 16 made of polyester resin, and an exterior resin through an intermediate material 13 made of acrylic resin. 10 is provided.

  Next, a specific method for manufacturing the solid electrolytic capacitor will be described.

  First, the surface of a rectangular aluminum foil having a thickness of 100 μm, which is the anode body 1, is roughened by electrochemical etching, and the anode lead portion 2 and the cathode portion side having a width of 3.5 mm and a length of 4.0 mm are provided. A polyimide adhesive tape was provided around the aluminum foil so as to be divided into two.

  The capacitor element 7 is configured by sequentially forming the dielectric oxide film 4, the solid electrolyte layer 5, and the cathode layer 6 on the surface of the anode body 1 on the cathode portion side.

  Specifically, the cathode part side of the anode body 1 is immersed in a 3% ammonium adipate aqueous solution, and anodization is performed for 60 minutes at an applied voltage of 12 V and an aqueous solution temperature of 70 ° C., and a dielectric oxidation made of aluminum oxide is performed. Form a film 4, then immerse in a 30% aqueous solution of manganese nitrate, air dry, and then subject to thermal decomposition at 300 ° C. for 10 minutes to form a manganese oxide layer that becomes part of the solid electrolyte layer 5 To do.

  Then, water as a solvent and propyl phosphate as a pH adjuster are added to a mixed liquid composed of 0.5 mol / L of monomer and 0.1 mol / L of sodium propylnaphthalenesulfonate to adjust the pH to 2. As a result, a polymerization liquid for forming a solid electrolyte system is obtained. Next, the cathode part side of the anode body 1 is immersed in the polymerization solution for forming a solid electrolyte system, the electrode for initiating polymerization is brought into proximity, and electrolytic oxidation polymerization is performed at a polymerization voltage of 1.5 V, and the surface of the conductive layer is formed. A solid electrolyte layer 5 made of polypyrrole is formed.

  Then, it is immersed in a carbon colloid solution, dried, and then immersed in a silver paste and cured at a temperature of 120 to 200 ° C., thereby forming a cathode layer 6 composed of a carbon layer and a silver paste.

  The anode terminal 8 and the cathode terminal 9 are made of a metal plate made of copper or copper alloy and having a thickness of 0.1 mm, and provided with an anode terminal connection portion 17 and a cathode terminal connection portion 18 corresponding to the anode lead portion 2 and the cathode layer 6, respectively. Is.

  A plurality of the capacitor elements 7 are laminated, the cathode layers 6 are connected to each other through a conductive paste, the anode terminal connection portion 17 is bent so as to wrap each anode lead portion 2, and the anode lead portion 2 is joined by welding, The cathode layer 6 on the lower surface of the capacitor element 7 in which the cathode terminal connection portions 18 having a width of 3.6 mm and a length of 4.2 mm are laminated so as to correspond to the shape of the cathode layer 6 is bonded via a conductive adhesive, The anode terminal 8 and the cathode terminal 9 were bent in steps so as to be exposed from the side surface of the capacitor body.

  Next, the solid capacitor main body 11 was formed by coating the laminated capacitor element 7, the anode terminal connection portion 17, and the cathode terminal connection portion 18 with an exterior resin 10 made of an epoxy resin by transfer molding. This epoxy resin contains an epoxy resin cured product of a main skeleton dicyclopentanediene type epoxy resin and a phenol novolac resin, and inorganic particles such as silica having an average particle diameter of 60 to 80 μm in a mass ratio of 80 to 90%. It has the structure made.

  Next, a laminate 19 composed of the barrier layer 12 and the intermediate material 13 is formed on the tape 22 and formed on the upper surface of the capacitor body 11 by transfer. As shown in FIG. 4, the laminate 19 has a protective layer 16 as a first layer, an inorganic layer 15 as a second layer, and an intermediate material 13 as a third layer on a tape 22 that is a supporting substrate. It has a laminated structure.

  Specifically, by applying and drying a mixed solution in which a silicone-based resin is dissolved on one side of a tape base material 20 made of an ethylene terephthalate resin film having a band-like thickness of 10 to 50 μm, a thickness of 0.01 to 1 μm is obtained. By forming the release layer 21, a tape 22 serving as a supporting substrate was obtained.

  A polyester resin was applied to the tape 22 and dried, and then an acrylic resin was further applied and dried to form a protective layer 16 as a first layer having a thickness of 2 μm. This acrylic resin improves the adhesion between the polyester resin of the protective layer 16 and the inorganic layer 15.

Next, the degree of vacuum in the vacuum apparatus is set to 5 × 10 ⁻⁶ to 10 ⁻⁴ Torr, and oxygen is introduced into the tape 21 on which the protective layer 16 installed on the cooling drum is introduced, while aluminum is electron-beamed. By heating and reacting with vaporized aluminum and oxygen, and depositing aluminum oxide as an inorganic material, an inorganic layer 15 as a second layer having a thickness of 40 nm was formed on the protective layer 16.

  Further, an acrylic resin is applied on the inorganic layer 15 and dried to form an intermediate material 13 as a third layer having a thickness of 3 μm on the inorganic layer 15, thereby forming a thickness of about 5 μm consisting of three layers. The laminate tape 23 was formed by forming the laminate 19 on the tape 22.

  Then, the laminated body 19 side of the laminated body tape 23 is brought into close contact with the upper surface of the capacitor body 11, and the heating body is pressed against the upper surface of the capacitor body 11 from the tape 22 side of the laminated body tape 23. Adhere to the upper surface of the main body 11.

  Next, when the laminate tape 23 is peeled from the capacitor body 11, the portion of the laminate 19 bonded to the upper surface of the capacitor 11 is cut off from the laminate tape 23, whereby the intermediate material 13 is placed on the upper surface of the capacitor body 11. A barrier layer 12 was provided on the exterior resin 10.

  This local heating was performed under the conditions of 150 to 200 ° C. and 1 to 60 seconds using a heating body having the same shape as the upper surface of the capacitor body 11.

  Next, the anode terminal 8 and the cathode terminal 9 exposed from the side surface of the capacitor body 11 are processed and bent so as to be in contact with the mounting surface on the lower surface, the outer dimensions are height 1.8 mm, width 4.3 mm, length 7.3 mm, A solid electrolytic capacitor 14 having a rated voltage of 2 V and a capacitance of 150 μF was obtained.

  In the above configuration, the inorganic material layer 15 prevents moisture and oxygen from entering from the outside through the exterior resin 10, so that the conductivity of the conductive polymer used for the solid electrolyte layer 5 is lowered and the ESR of the solid electrolytic capacitor 14 is increased. The effect that can be prevented by the barrier layer 12 is obtained.

  In particular, since at least the solid electrolyte layer 5 is interposed between the barrier layer 12 and the cathode terminal connection portion 18, the cathode terminal connection portion 18 prevents moisture and oxygen from entering from the lower surface of the capacitor body 11. Therefore, by providing the barrier layer 12 only on the upper surface of the capacitor body 11, it is possible to effectively prevent the characteristic change of the solid electrolytic capacitor.

  In this case, if the width of the cathode terminal connection portion 18 is increased and the side surface of the capacitor element 7 is also covered, the characteristic change can be further prevented.

  Further, if the inorganic layer 15 made of an insulator is formed, there is no possibility of conduction due to contact with the barrier layer 12 from the outside without providing the protective layer 16.

  Furthermore, by using the laminate tape 23 in which the laminate 19 is formed on the tape 22, the laminate 19 can be continuously transferred to the capacitor body 11.

  In addition, although the foil of aluminum which is a valve action metal was used for the anode body 1, you may use the porous sintered compact which consists of valve action metal foils, such as aluminum, a tantalum, niobium, titanium, or valve action metal powder. .

  The solid electrolyte layer 5 is made of polypyrrole, but may be made of a conductive polymer such as polythiophene or polyaniline.

  In the embodiment, the cathode terminal connection portion 18 is bonded to the lower surface of the capacitor element 7. However, the cathode terminal connecting portion 18 may be bent at both ends of the capacitor element 7 so as to be bonded along the side surface of the cathode layer 6.

  The thickness of the protective layer 16 is preferably 1 μm or more so that the exposure of the inorganic layer 15 can be reduced by physical or chemical damage.

  The constituent material used for the exterior resin 10 is not limited to an epoxy resin, but may be an insulating resin having heat resistance.

  Further, by increasing the flatness of the surface of the exterior resin 10, the adhesion with the barrier layer 12 can be improved even if the intermediate material 13 is thin. When the exterior resin 10 is formed by transfer molding, If the thickness of the material 13 is 1 to 10 μm, sufficient adhesion can be obtained.

  The material used for the release layer 21 may be a fluorine-based resin, a melanin resin, a nitrocellulose resin, a wax, or a surfactant that has an effect of releasing the tape 22 and the protective layer 16.

  As a material used for the intermediate material 13, a mixed coating liquid of a high molecular weight epoxy polymer composed of bisphenol A type epoxy resin and phenol, an oxyanhydride-based curing agent, and an organic solvent is used, and is applied by a reverse coating method. The intermediate material 13 made of an uncured epoxy resin may be formed by heat drying at a temperature that does not cause a curing reaction, for example, 50 to 100 ° C.

  After forming the barrier layer 12 on the exterior resin 10, the adhesion between the barrier layer 12 and the exterior resin 10 may be improved by heat treatment.

  Furthermore, as a method for forming the release layer 21, the protective layer 16, and the intermediate material 13, coating may be performed by a gravure coating method, a reverse coating method, or the like that applies an organic solvent or an aqueous solution of a resin or a mixture.

  Note that when the structure of this embodiment is used and a manganese oxide containing manganese dioxide or the like is used for a solid electrolyte, an increase in leakage current due to moisture intrusion from the outside can be prevented.

  In addition, in order to improve the appearance of the barrier layer 12 formed on the upper surface of the capacitor body 11, half-cutting is performed in advance on the laminated body 19 side of the laminated body tape 22 in accordance with the upper surface outline of the capacitor body 11, and the laminated body tape 23. May be transferred by positioning. Alternatively, a laminate tape 23 in which the laminate 19 corresponding to the upper surface shape of the capacitor body 11 is formed by forming the laminate 19 on the masked tape 22 may be used.

  Furthermore, the laminate 19 may be bonded to the upper surface of the capacitor 11 and the tape 22 may be peeled off by cutting the laminate tape 23 according to the shape of the upper surface of the capacitor body 11.

  In the present embodiment, the supporting base material is the tape 22 in which the release layer 21 is formed on the tape base material 20. However, if the support base material is peelable from the laminate 19 and the laminate 19 can be formed. A metal transfer roller or the like may be used as the support substrate.

(Embodiment 2)
The second embodiment is different from the first embodiment only in the configuration of the barrier layer 25, and the description of the first embodiment is used for other configurations and manufacturing methods.

  As shown in FIG. 5, the barrier layer 25 is composed of a protective layer 16 and a metal layer 26.

  This protective layer 16 is formed by the same material and forming method as in the first embodiment, and the thickness thereof is 1 μm or more so that the exposure of the metal layer 26 can be reduced by physical or chemical damage. Is preferred.

Specifically, the degree of vacuum in the vacuum apparatus is 5 × 10 ⁻⁶ to 10 ⁻⁴ Torr, aluminum is heated by an electron beam, and aluminum is applied to the tape 22 on which the protective layer 16 installed on the cooling drum is formed. A metal layer 26 having a thickness of 50 nm was formed on the protective layer 16 by vapor deposition.

  In the above configuration, since the metal layer 26 of the barrier layer 25 prevents moisture and oxygen from entering from the outside through the exterior resin 10 of the capacitor body 11, it is possible to suppress changes in the characteristics of the solid electrolytic capacitor.

(Embodiment 3)
The third embodiment is different from the first embodiment only in the configuration of the barrier layer 27, and the description of the first embodiment is used for other configurations and manufacturing methods.

  As shown in FIG. 6, the configuration of the barrier layer 27 is made up of a protective layer 16, an inorganic layer 29, and a metal layer 28.

  This protective layer 16 is formed by the same material and forming method as in the first embodiment, and its thickness is 1 μm so that exposure of the metal layer 28 and the inorganic layer 29 can be reduced by physical or chemical damage. The above is preferable.

Specifically, the degree of vacuum in the vacuum apparatus is 5 × 10 ⁻⁶ to 10 ⁻⁴ Torr, and aluminum is heated by an electron beam while introducing oxygen, thereby forming the protective layer 16 installed on the cooling drum. By depositing aluminum on the tape 22, an inorganic layer 29 having a thickness of 40 nm was formed on the protective layer 16.

  Subsequently, aluminum is heated by an electron beam, and aluminum is vapor-deposited on the tape 22 on which the inorganic layer 29 formed on the cooling drum is deposited, thereby forming a metal layer 28 having a thickness of 50 nm on the inorganic layer 29. I did it.

  In the above configuration, since the metal layer 28 and the inorganic layer 29 of the barrier layer 27 prevent moisture and oxygen from entering from the outside through the exterior resin 10 of the capacitor body 11, it is possible to suppress changes in characteristics of the solid electrolytic capacitor. .

(Embodiment 4)
The fourth embodiment is different from the first embodiment only in the configuration of the barrier layer 30, and the description of the first embodiment is used for other configurations and manufacturing methods.

  As shown in FIGS. 7 and 8, the barrier layer 30 is composed of a protective layer 32 and a metal foil 31.

  The protective layer 32 is made of the same material as that used in the first embodiment, and the same formation method is used. The thickness of the protective layer 32 can be reduced by physical or chemical damage. It is preferable that it is 1 micrometer or more.

  Specifically, an aluminum foil formed to a thickness of 1 μm by a rolling method is placed on the tape 22 on which the protective layer 32 serving as the first layer placed on the cooling plate is formed, and 200 ° C. in an argon atmosphere. By pressure-bonding under the conditions, a metal foil 31 serving as a second layer having a thickness of 1 μm was laminated on the protective layer 32.

  Furthermore, by applying and drying an acrylic resin, the intermediate material 13 as a third layer having a thickness of 3 μm is formed on the metal foil 31, so that the laminated body 33 having a thickness of about 6 μm consisting of three layers is supported on the support base. The laminated body tape 34 was comprised by forming on the tape 22 which is material.

  In the above configuration, the metal foil 31 of the barrier layer 30 prevents moisture and oxygen from entering from the outside through the exterior resin 10 of the capacitor body 11, so that it is possible to suppress changes in the characteristics of the solid electrolytic capacitor.

  In particular, it is possible to form a barrier layer having excellent mechanical strength by using a metal foil formed by a rolling method and having improved mechanical strength by heat treatment.

(Comparative example)
In the first embodiment, a capacitor body 11 in which the barrier layer 12 is not provided on the exterior resin 10 is used as a conventional comparative example.

  About the solid electrolytic capacitors of the first to fourth embodiments and the comparative example, after mounting by reflowing at a peak temperature of 260 ° C. for 10 seconds twice, a high temperature no-load test test of 125 ° C., a temperature of 85 ° C., and a relative humidity Table 1 shows the measurement results of the ESR at a frequency of 100 kHz and the capacitance change rate at a frequency of 120 Hz.

  As apparent from Table 1, the solid electrolytic capacitors of Embodiments 1 to 4 were tested, and as a result, changes in ESR and capacitance were reduced as compared with the comparative example which is a conventional product.

  This is presumably because the barrier layer provided in the solid electrolytic capacitors of Embodiments 1 to 4 prevented moisture and oxygen from entering through the exterior resin from the outside.

  As described above, the solid electrolytic capacitor of the present invention can stabilize the characteristics of the solid electrolytic capacitor by forming the barrier layer composed of the metal layer and / or the inorganic layer on the exterior resin. Even if it is thin, the effect can be sufficiently exhibited.

  The same effect can be obtained by forming a barrier layer made of a metal foil on the exterior resin.

  In the solid electrolytic capacitor according to the present invention, a barrier layer composed of a metal layer and / or an inorganic layer is provided on an exterior resin, and the metal layer and / or the inorganic layer is formed by a vapor phase growth method. Even if the barrier layer is thin without deterioration, the metal layer and / or inorganic layer has a dense structure, which can improve the moisture and oxygen shielding properties from the outside. It is possible to obtain an effect that a solid electrolytic capacitor that can be used and used in various electronic devices and vehicle circuits having stable characteristics can be provided.

  A similar effect can be obtained by providing a barrier layer made of a metal foil on the exterior resin and forming the metal foil by a rolling method.

Sectional drawing of the solid electrolytic capacitor in Embodiment 1 of this invention Sectional drawing of the capacitor | condenser element in the same Embodiment 1 Sectional drawing of the barrier layer in Embodiment 1 Sectional drawing of the laminated body tape in Embodiment 1 Sectional drawing of the barrier layer in Embodiment 2 of this invention Sectional drawing of the barrier layer in Embodiment 3 of this invention Sectional drawing of the barrier layer in Embodiment 4 of this invention Sectional drawing of the laminated body tape in Embodiment 4 Cross section of a conventional solid electrolytic capacitor A perspective sectional view of a conventional capacitor element

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Anode body 4 Dielectric oxide film 5 Solid electrolyte layer 6 Cathode layer 7 Capacitor element 8 Anode terminal 9 Cathode terminal 10 Exterior resin 11 Capacitor body 12, 25, 27, 30 Barrier layer 13 Intermediate material 15, 29 Inorganic layer 16, 32 Protective layer 18 Cathode terminal connection 19, 33 Laminate 22 Tape 26, 28 Metal layer 31 Metal foil

Claims (7)

A capacitor element in which a dielectric oxide film is formed on the surface of an anode body made of a valve metal and a solid electrolyte layer made of a conductive polymer and a cathode layer are sequentially formed thereon, and an anode terminal and a cathode terminal are formed on the capacitor element. In a solid electrolytic capacitor in which an exterior resin is formed to connect and cover this capacitor element, a barrier layer made of a metal layer and / or an inorganic layer is formed on the exterior resin to prevent moisture and oxygen from entering from the outside. A solid electrolytic capacitor in which the metal layer and / or the inorganic material layer is formed by a vapor phase growth method, and an intermediate material is interposed between the exterior resin and the barrier layer. The solid electrolytic capacitor according to claim 1, wherein a barrier layer is composed of a metal layer and / or an inorganic layer and a protective layer formed thereon. A capacitor element in which a dielectric oxide film is formed on the surface of an anode body made of a valve action metal and a solid electrolyte layer made of a conductive polymer and a cathode layer are sequentially formed thereon has an anode terminal and a cathode terminal In a solid electrolytic capacitor in which an exterior resin is formed so as to cover and cover this capacitor element, a barrier layer made of a metal foil is provided on the exterior resin to prevent moisture and oxygen from entering from the outside. Is a solid electrolytic capacitor formed by a rolling method and further having an intermediate material interposed between the exterior resin and the barrier layer. The solid electrolytic capacitor according to claim 3, wherein a barrier layer is constituted by a metal foil and a protective layer formed thereon. The solid electrolytic capacitor according to claim 1, wherein at least a solid electrolyte layer is interposed between the cathode terminal connection portion and the barrier layer. A step of forming a protective layer as a first layer on a supporting substrate, a step of forming a metal layer and / or an inorganic layer as a second layer on the first layer by vapor deposition, and a third layer Forming an intermediate material to be formed on the second layer to sequentially form a three-layer laminate on the support substrate, and transferring the laminate to a solid electrolytic capacitor exterior resin. A method for producing a solid electrolytic capacitor. A step of forming a protective layer as a first layer on a supporting substrate, a step of laminating a metal foil formed by a rolling method as a second layer on the first layer, and an intermediate material as a third layer. Production of a solid electrolytic capacitor in which the step of forming a laminate composed of three layers on a support substrate by forming on the second layer and the step of transferring the laminate to the exterior resin of the solid electrolytic capacitor are sequentially performed Method.

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