JP2018067572A - Solid electrolytic capacitor, and method for manufacturing solid electrolytic capacitor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solid electrolytic capacitor which can suppress the degradation of a solid electrolyte layer with time.SOLUTION: A solid electrolytic capacitor 100 comprises: at least one capacitor element 170 having an anode part including a metal layer 141 and having an outer surface with a plurality of concave portions provided therein, a dielectric layer 150 provided on the outer surface of the metal layer 141, a solid electrolyte layer 165 provided on at least a part of an outer surface of the dielectric layer 150 and having a conductive polymer, and a cathode part 160 having current collector layers 161, 162 provided on an outer surface of the solid electrolyte layer 165; and an insulative resin body 110 in which the at least one capacitor element 170 is provided. In the solid electrolytic capacitor, a portion surrounding the at least one capacitor element 170 is in a low-humidity condition in which it contains such an amount of a moisture that the dew point temperature is 5°C or below.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a solid electrolytic capacitor containing a conductive polymer in a solid electrolyte and a method for manufacturing the solid electrolytic capacitor.

  As a document disclosing a conventional method of manufacturing a solid electrolytic capacitor, for example, Japanese Patent Application Laid-Open No. 2008-135427 (Patent Document 1) is cited.

  In the method for manufacturing a solid electrolytic capacitor disclosed in Patent Document 1, a plurality of capacitor elements are laminated on an anode terminal and a cathode terminal and joined together, and a plurality of anode terminals and cathode terminals are joined together. Capacitor elements are placed in a molding die, and a part of the anode terminals and the cathode terminals are removed, and a plurality of capacitor elements joined to the anode terminals and cathode terminals are integrated with an insulating exterior resin. And a coating step. In the process of integrally covering a plurality of capacitor elements to which the anode terminal and cathode terminal are bonded with an insulating exterior resin, a slide pin for positioning the cathode terminal by contacting the lower surface of the cathode terminal is disposed on the molding die. The molten exterior resin is injected into the molding die, and after the resin is cured, the slide pin is removed from the exterior resin.

  By arranging a slide pin for positioning the cathode terminal by contacting the lower surface of the cathode terminal to the molding die, the capacitor element and the cathode terminal are not injected even when a molten exterior resin is injected into the molding die at a high pressure. Since it is not deformed by the injection pressure, it becomes possible to perform molding with high dimensional accuracy, and it is possible to realize a small size and a large capacity.

JP 2008-135427 A

  However, in the solid electrolytic capacitor disclosed in Patent Document 1, there is no particular mention about the environment of the surrounding atmosphere when molding. For this reason, depending on the indoor environment, a considerable amount of moisture and oxygen remain around the plurality of capacitor elements in the state after resin molding.

  In such a case, dedoping of the conductive polymer proceeds with moisture and oxygen, and the solid electrolyte layer containing the conductive polymer deteriorates with time. Thereby, ESR will increase.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a solid electrolytic capacitor and a method for manufacturing the solid electrolytic capacitor that can suppress deterioration over time of the solid electrolyte. .

  The solid electrolytic capacitor according to the first aspect of the present invention has an outer surface provided with a plurality of recesses, an anode part made of a metal layer, a dielectric layer provided on the outer surface of the metal layer, At least one or more including a solid electrolyte layer having a conductive polymer provided on at least a part of the outer surface of the dielectric layer and a current collector layer provided on the outer surface of the solid electrolyte layer And an insulating resin body in which the at least one or more capacitor elements are provided, and the water around the at least one or more capacitor elements is a dew point temperature of 5 ° C. or less. It is in a low humidity state including.

  The solid electrolytic capacitor according to the second aspect of the present invention has an outer surface provided with a plurality of recesses, an anode part made of a metal layer, a dielectric layer provided on the outer surface of the metal layer, At least one including a solid electrolyte layer having a conductive polymer provided on at least a part of the outer surface of the dielectric layer and a cathode portion having a current collector layer provided on the outer surface of the solid electrolyte layer The above capacitor element and an insulating resin body in which at least one or more capacitor elements are provided are provided, and the periphery of the at least one capacitor element is compared with the outside of the insulating resin body. And it is in a low oxygen state.

  In the solid electrolytic capacitor according to the second aspect of the present invention, the periphery of the at least one capacitor element may be in a low-humidity state containing water in an amount such that the dew point temperature is 5 ° C. or less. .

  The solid electrolytic capacitor according to the first aspect and the second aspect of the present invention is electrically connected to the cathode portion inside the insulating resin body and drawn out of the insulating resin body. One terminal and a second terminal that is electrically connected to the anode part inside the insulating resin body and led out of the insulating resin body may be further provided.

  The solid electrolytic capacitor according to the first aspect and the second aspect of the present invention is electrically connected to the cathode portion through the lead conductor layer connected to the current collector layer and the lead conductor layer. And a first external electrode and a second external electrode electrically connected to the anode part. In this case, it is preferable that the insulating resin body has a first end surface and a second end surface that face each other in the extending direction of the metal layer. The first external electrode is preferably provided on the first end face, and the second external electrode is preferably provided on the second end face. Further, in this case, the lead conductor layer is preferably drawn to the first end face side and connected to the first external electrode, and is one end side of the metal layer exposed from the cathode portion. Is preferably drawn to the second end face side and connected to the second external electrode.

  In the solid electrolytic capacitor according to the first aspect and the second aspect of the present invention, the insulating resin body has an uncovered region that does not cover a part of the at least one capacitor element. A first insulating resin body and a second insulating resin body that fills the uncovered region and covers the part of the at least one capacitor element may be included.

  A method of manufacturing a solid electrolytic capacitor according to the first aspect of the present invention includes an anode having an outer surface provided with a plurality of recesses, an anode formed of a metal layer, and a dielectric provided on the outer surface of the metal layer. At least a part of the outer surface of the dielectric layer, a solid electrolyte layer having a conductive polymer, and a cathode portion having a current collector layer provided on the outer surface of the solid electrolyte layer Providing one or more capacitor elements; and providing the at least one capacitor element inside an insulating resin body, wherein the at least one capacitor element is disposed inside the insulating resin body. The step of providing includes a step of molding the at least one capacitor element using an insulating resin member, and the step of molding the at least one capacitor element. , Molding the said at least one capacitor element with low saturated vapor pressure dew point temperature is 5 ° C. or less.

  A method for manufacturing a solid electrolytic capacitor according to a second aspect of the present invention includes an anode having an outer surface provided with a plurality of recesses, an anode formed of a metal layer, and a dielectric provided on the outer surface of the metal layer. At least a part of the outer surface of the dielectric layer, a solid electrolyte layer having a conductive polymer, and a cathode portion having a current collector layer provided on the outer surface of the solid electrolyte layer Providing one or more capacitor elements; and providing the at least one capacitor element inside an insulating resin body, wherein the at least one capacitor element is disposed inside the insulating resin body. The step of providing includes a step of molding the at least one capacitor element using an insulating resin member, and the step of molding the at least one capacitor element. , Molding the said at least one capacitor element under oxygen environment.

  In the method for producing a solid electrolytic capacitor according to the second aspect of the present invention, in the step of molding the at least one capacitor element, the method is performed under a low saturated water vapor pressure at which a dew point temperature is 5 ° C. or less. At least one capacitor element may be molded.

  A method for manufacturing a solid electrolytic capacitor according to a third aspect of the present invention includes an anode having an outer surface provided with a plurality of recesses, an anode formed of a metal layer, and a dielectric provided on the outer surface of the metal layer. At least a part of the outer surface of the dielectric layer, a solid electrolyte layer having a conductive polymer, and a cathode portion having a current collector layer provided on the outer surface of the solid electrolyte layer Providing one or more capacitor elements, and providing the at least one capacitor element in an insulating resin body. The step of providing the at least one or more capacitor elements inside the insulating resin body includes a step of molding the at least one or more capacitor elements using an insulating resin member, and the at least one or more capacitors. The step of molding the element includes a step of forming a first insulating resin body having a non-covering region that does not cover a part of the at least one capacitor element using the first resin material, and the non-covering step. The method further includes supplying an inert gas around the at least one capacitor element through the region, and sealing the non-covered region with a second resin material.

  In the method for producing a solid electrolytic capacitor based on the first aspect, the second aspect, and the third aspect of the present invention, the step of providing the at least one capacitor element inside the insulating resin body. Includes a step of arranging the first terminal piece and the second terminal piece in a straight line in a state of being separated from each other, and the cathode portion side of the capacitor element is placed on the first terminal piece and exposed from the cathode portion. Laminating the at least one capacitor element on the first terminal piece and the second terminal piece so that the metal layer of the capacitor element of the part to be placed on the second terminal piece; May further be included. In this case, in the step of molding the at least one capacitor element, the end side of the first terminal piece located on the side opposite to the second terminal piece side and the side opposite to the first terminal piece side It is preferable that the first terminal piece, the second terminal piece, and the at least one capacitor element are molded so that the end portion side of the second terminal piece located at is exposed.

  In the solid electrolytic capacitor according to the first aspect, the second aspect, and the third aspect of the present invention, the step of providing the at least one or more capacitor elements inside the insulating resin body is an insulating process. A step of laminating the at least one capacitor element on the conductive resin substrate. In this case, in the step of molding the at least one capacitor element, it is preferable to mold the at least one capacitor element on the insulating resin substrate.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the solid electrolytic capacitor which can suppress deterioration with time of a solid electrolyte layer, and a solid electrolytic capacitor can be provided.

1 is a cross-sectional view showing a solid electrolytic capacitor according to a first embodiment. It is sectional drawing which expands and shows the II section shown in FIG. It is sectional drawing along the III-III line | wire shown in FIG. 3 is a diagram showing a manufacturing flow of the solid electrolytic capacitor according to Embodiment 1. FIG. 6 is a cross-sectional view showing a solid electrolytic capacitor according to Embodiment 2. FIG. 6 is a diagram showing a manufacturing flow of a solid electrolytic capacitor according to Embodiment 2. FIG. 6 is a perspective view showing a solid electrolytic capacitor according to Embodiment 3. FIG. It is sectional drawing along the VIII-VIII line shown in FIG. It is sectional drawing along the IX-IX line | wire shown in FIG. FIG. 10 is a diagram showing a manufacturing flow of the solid electrolytic capacitor according to the third embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following embodiments, the same or common parts are denoted by the same reference numerals in the drawings, and description thereof will not be repeated.

(Embodiment 1)
(Solid electrolytic capacitor)
1 is a cross-sectional view showing a solid electrolytic capacitor according to Embodiment 1. FIG. FIG. 2 is an enlarged cross-sectional view of the II part shown in FIG. FIG. 3 is a cross-sectional view taken along line III-III shown in FIG. A solid electrolytic capacitor 100 according to Embodiment 1 will be described with reference to FIGS. 1 to 3. 1 and 3 and the like, the length direction of an insulating resin body to be described later is indicated by L, the height direction of the insulating resin body is indicated by T, and the width direction of the insulating resin body is indicated by W. The height direction T is orthogonal to the length direction L, and the width direction W is orthogonal to each of the length direction L and the height direction T.

  As shown in FIGS. 1 to 3, the solid electrolytic capacitor 100 according to the first embodiment has a substantially rectangular parallelepiped outer shape. In the first embodiment, the outer dimensions of the solid electrolytic capacitor 100 are, for example, a dimension in the length direction L of 7.3 mm, a dimension in the width direction W of 4.3 mm, and a dimension in the height direction T of 1.9 mm. .

  Solid electrolytic capacitor 100 includes a plurality of capacitor elements 170, insulating resin body 110, first terminal 120, and second terminal 130.

  The insulating resin body 110 has a substantially rectangular parallelepiped outer shape. A plurality of capacitor elements 170 are provided inside the insulating resin body 110. The insulating resin body 110 includes a first main surface 110a and a second main surface 110b opposed in the height direction T, a first side surface 110c and a second side surface 110d opposed in the width direction W, and a relative relationship in the length direction L. A first end face 110e and a second end face 110f.

  As described above, the insulating resin body 110 has a substantially rectangular parallelepiped outer shape, but the corner portions and the ridge line portions may be rounded. The corner portion is a portion where three surfaces of the insulating resin body 110 intersect, and the ridge line portion is a portion where two surfaces of the insulating resin body 110 intersect. Irregularities may be formed on at least one of the first main surface 110a, the second main surface 110b, the first side surface 110c, the second side surface 110d, the first end surface 110e, and the second end surface 110f.

  The insulating resin body 110 is made of an insulating resin such as an epoxy resin in which glass or silicon (Si) oxide is dispersed and mixed as a filler.

  Each of the plurality of capacitor elements 170 includes an anode part, a dielectric layer 150, a solid electrolyte layer 165, and a cathode part 160. The plurality of capacitor elements 170 are stacked on each other in the height direction T. A part of the plurality of capacitor elements 170 is laminated on one side of the first terminal 120 and the second terminal 130 in the height direction T. The remaining portions of the plurality of capacitor elements 170 are stacked on the other side of the first terminal 120 and the second terminal 130 in the height direction.

  Among the plurality of capacitor elements 170, the capacitor element located on the one side in the stacking direction of the capacitor elements 170 is referred to as a first capacitor element 170a, and the capacitor element located on the other side is referred to as a second capacitor element 170b.

  A region R1 around the plurality of capacitor elements 170 is in a low-humidity state containing water in an amount that results in a dew point temperature of 5 ° C. or lower. In addition, the region R1 around the plurality of capacitor elements 170 is in a lower oxygen state than the outside of the insulating resin body 110.

  Here, in the manufacturing process to be described later, when the plurality of capacitor elements 170 are molded using the insulating resin to be the insulating resin body 110, the plurality of capacitor elements are covered with gas in the environment. Molded. Therefore, a minute space communicating along the periphery of the plurality of capacitor elements 170 is formed by the gas remaining in the insulating resin. The region R1 of the plurality of capacitor elements 170 is constituted by this minute space. This minute space is in a low-humidity state that includes an amount of water that has a dew point temperature of 5 ° C. or lower, and is in the low-oxygen state. The partial pressure of oxygen in the minute space is preferably 10 [kPa] or less, for example.

  Note that the low oxygen state means that the concentration of an inert gas such as nitrogen and argon is higher than the outside air of the insulating resin body 110, so that the oxygen concentration in the space becomes higher than that of the insulating resin body 110. It is a state that is lower than the outside air.

  The anode part is made of, for example, a metal layer 141. The metal layer 141 has an outer surface provided with a plurality of recesses. The outer surface of the metal layer 141 is porous. Since the outer surface of the metal layer 141 is porous, the surface area of the metal layer 141 is increased. Note that the present invention is not limited to the case where both the front and back surfaces of the metal layer 141 are porous, and only one of the front and back surfaces of the metal layer 141 may be porous. For example, only the back surface of the metal layer 141 on the side facing the second main surface 110b of the insulating resin body 110 may be porous.

  The metal layer 141 has a flat plate shape. The metal layer 141 is made of, for example, a metal foil. Specifically, the metal layer 141 is made of an aluminum foil. Note that the metal layer 141 is not limited to aluminum, and may be composed of a single metal such as tantalum, niobium, titanium, zirconium, magnesium, and silicon, or a valve metal such as an alloy thereof or an aluminum alloy. . An oxide film can be formed on the surface of the valve metal.

  In addition, the anode part should just be comprised by the porous part provided in the circumference | surroundings of the core part and the said core part, what etched the metal rolling foil (the said metal foil), and was porous in the said metal rolling foil What formed the quality fine powder sintered compact can be employ | adopted suitably.

  The dielectric layer 150 is provided on the outer surface of the metal layer 141. In the first embodiment, the dielectric layer 150 is constituted by, for example, an oxide film provided on the surface of the valve metal. Specifically, the dielectric layer 150 is made of an oxide of aluminum. As will be described later, the aluminum oxide is formed by anodizing the outer surface of the metal layer 141.

  The solid electrolyte layer 165 is provided on a part of the outer surface of the dielectric layer 150. The solid electrolyte layer 165 is not provided on the outer surface of the dielectric layer 150 provided on the outer surface of the metal layer 141 located near the second end face 110f. In this portion of the dielectric layer 150, the outer surface of the portion adjacent to the portion where the solid electrolyte layer 165 is provided is covered with an insulating layer 151 described later.

  As shown in FIG. 2, the solid electrolyte layer 165 is provided so as to fill a plurality of concave portions of the metal layer 141. However, the part of the outer surface of the dielectric layer 150 may be covered with the solid electrolyte layer 165, and a recess of the metal layer 141 that is not filled with the solid electrolyte layer 165 may exist.

  The solid electrolyte layer 165 can be formed of any of a conductive polymer, a conductive organic material, a conductive inorganic oxide, and the like, for example. In this capacitor element 170, for example, a conductive polymer film such as poly (3,4-ethylenedioxythiophene) is used as the solid electrolyte layer 165.

  In general, a dopant is used for the conductive polymer, and any dopant compound can be used as the dopant. For example, organic sulfonic acid, inorganic sulfonic acid, organic carboxylic acid and salts thereof can be used. In general, an aryl sulfonate dopant is used. For example, salts such as benzenesulfonic acid, toluenesulfonic acid, naphthalenesulfonic acid, anthracenesulfonic acid, anthraquinonesulfonic acid, or substituted derivatives thereof can be used.

  The cathode unit 160 includes a first current collector layer 161 and a second current collector layer 162. The first current collector layer 161 is provided on the outer surface of the solid electrolyte layer 165. The second current collector layer 162 contains carbon. The second current collector layer 162 contains silver.

  As described above, in the portion of the dielectric layer 150 where the solid electrolyte layer 165 is not provided, the portion adjacent to the portion where the solid electrolyte layer 165 is provided has a composition different from that of the insulating resin body 110. The outer surface is covered with the insulating layer 151.

  The insulating layer 151 is formed, for example, by applying a masking agent such as a composition made of insulating resin, inorganic fine powder and cellulose resin. Although not limited to insulating materials, specific examples include, for example, polyphenylsulfone (PPS), polyethersulfone (PES), cyanate ester resin, fluororesin (tetrafluoroethylene, tetrafluoroethylene / perfluoroalkyl). Vinyl ether copolymers, etc.), low molecular weight polyimides and derivatives thereof, precursors thereof, compositions composed of soluble polyimide siloxane and epoxy resin, and the like.

  As shown in FIGS. 1 and 3, the current collector layers of the capacitor elements 170 adjacent to each other in the stacking direction are electrically connected to each other by the connection conductor layer 190. The width of the connection conductor layer 190 in the width direction W is equal to the width of the metal layer 141 in the width direction W. The connection conductor layer 190 contains silver. The connection conductor layer 190 is made of, for example, a conductive adhesive material.

  End portions near the second end face 110f in the metal layers 141 of the capacitor elements 170 adjacent to each other in the stacking direction are electrically connected to each other by resistance welding or the like.

  In this case, it is preferable that low melting point metal plating is applied to the end portion side of the second terminal 130 on the side located inside the insulating resin body 110. The anode portion where the dielectric layer 150 is exposed from the cathode portion 160 is overlaid on the portion where the low melting point metal plating is applied. Resistance welding is performed on the portion where the anode portion is overlapped. By performing resistance welding, the portion where the anode portions are overlapped generates heat due to the specific resistance of the dielectric layer 150 on the end portion side of the anode portion near the second end face 110f. Thereby, the low melting point metal plating of the second terminal 130 is melted, and the second terminal 130 and the end portion of the anode part are joined together.

  Further, when an aluminum conversion foil is used as the metal layer 141, the surface of the aluminum conversion foil is melted by the heat generated by the oxide film as the dielectric layer 150, and the surface of the aluminum conversion foil in the overlapped portion is mutually bonded. Melt and join together.

  As described above, the end portions of the metal layer 141 between the capacitor elements 170 near the second end face 110f are electrically connected by another connection conductor layer that is electrically insulated from the connection conductor layer 190. Also good. Other connection conductor layers may be formed of a conductive adhesive.

  The plurality of capacitor elements 170 are arranged in a fan shape so that the tip ends of the cathode portion 160 are separated from each other in the height direction T when viewed in a cross section parallel to the height direction T and the length direction L. The plurality of capacitor elements 170 are arranged so that the inclination of the metal layer 141 in the portion covered with the cathode portion 160 increases as the distance from the first terminal 120 in the portion located inside the insulating resin body 110 increases. Yes.

  The first terminal 120 is a lead frame. The first terminal 120 is electrically connected to the cathode portion 160 of each of the plurality of capacitor elements 170 and is drawn out of the insulating resin body 110. In the first terminal 120, the portion located inside the insulating resin body 110 faces the current collector layers of the two capacitor elements 170 adjacent to each other in the stacking direction, and each of the current collector layers And the connection conductor layer 190. In the first terminal 120, the portion located outside the insulating resin body 110 is bent along the first end surface 110 e and the second main surface 110 b of the insulating resin body 110.

  The second terminal 130 is a lead frame. The second terminal 130 is electrically connected to the anode portion of each of the plurality of capacitor elements 170 and is drawn out to the outside of the insulating resin body 110. In the second terminal 130, the portion located inside the insulating resin body 110 is sandwiched between the end portions near the second end face 110f of the metal layer 141 of the two capacitor elements 170 adjacent to each other in the stacking direction. These are connected to each of the metal layers 141 by resistance welding or the like. In the second terminal 130, the portion located outside the insulating resin body 110 is bent along the second end surface 110 f and the second main surface 110 b of the insulating resin body 110.

  As described above, in the solid electrolytic capacitor 100 according to the first embodiment, an amount in which the region R1 around the plurality of capacitor elements 170 provided in the insulating resin body 110 has a dew point temperature of 5 ° C. or less. It is in a low humidity state containing the above water and the low oxygen state.

  Thereby, even if the gas remaining in the region R1 around the plurality of capacitor elements 170 enters the solid electrolyte layer 165, it is possible to prevent the conductive polymer from being dedoped by moisture and oxygen. Can do. As a result, the solid electrolyte layer can suppress deterioration over time, and the reliability of the solid electrolytic capacitor 100 can be improved.

(Method for manufacturing solid electrolytic capacitor)
FIG. 4 is a diagram showing a manufacturing flow of the solid electrolytic capacitor according to the first embodiment. A manufacturing flow of the solid electrolytic capacitor according to the first embodiment will be described with reference to FIG.

  As shown in FIG. 4, when manufacturing the solid electrolytic capacitor 100, first, at least one or more capacitor elements 170 are prepared in step S10. In the first embodiment, a plurality of capacitor elements 170 are prepared. Specifically, a plurality of metal layers 141 are prepared, and the following steps S11 to S14 are performed.

  First, in step S11, the dielectric layer 150 is provided on the outer surface of the metal layer 141. In the present embodiment, an aluminum oxide serving as the dielectric layer 150 is formed by immersing an aluminum foil as the metal layer 141 in an aqueous solution of ammonium adipate and performing anodization. When the aluminum foil on which aluminum oxide has already been formed is cut and used as the metal layer 141, the cut metal layer 141 is made of ammonium adipate in order to form aluminum oxide on the cut surface. It is immersed again in an aqueous solution and anodized.

  Next, a part of the metal layer 141 is masked in step S12. This masking is performed in order to define the formation region of the solid electrolyte layer 165 to be performed in the next step. Specifically, a masking agent made of an insulating resin such as a polyimide resin or a polyamideimide resin is applied to a part of the outer surface of the metal layer 141. The masking portion formed by this process becomes the insulating layer 151.

  Next, in step S <b> 13, the solid electrolyte layer 165 is provided on a part of the outer surface of the dielectric layer 150. Specifically, the outer surface of the dielectric layer 150 located in the formation region of the solid electrolyte layer 165 defined by the masking portion formed in step S12 includes 3,4-ethylenedioxythiophene and an oxidizing agent. A treatment liquid is attached to form a polymerized film. The treatment liquid is a dispersion of a conductive polymer, and this polymerized film becomes the solid electrolyte layer 165.

  Next, a current collector layer is provided on the outer surface of the solid electrolyte layer 165 in step S14. Specifically, the first current collector layer 161 is formed on the outer surface of the solid electrolyte layer 165 by applying carbon. A second current collector layer 162 is formed on the outer surface of the first current collector layer 161 by applying silver.

  At least one capacitor element 170 is prepared through steps S11 to S14.

  Next, in step S <b> 20, at least one capacitor element 170 is provided inside the insulating resin body 110. In the first embodiment, a plurality of capacitor elements 170 are provided inside insulating resin body 110. Specifically, the following step S21 and step S22 are performed.

  First, in step S21, the first terminal piece to be the first terminal 120 and the second terminal piece to be the second terminal 130 are linearly arranged in a state of being separated from each other. The first terminal piece and the second terminal piece are in a state before being bent and have a plate shape.

  Next, in step S <b> 22, the capacitor element 170 is stacked on the first terminal 120 and the second terminal 130. Specifically, the cathode portion 160 side of the capacitor element 170 is placed on the first terminal piece, and the portion of the metal layer 141 of the capacitor element 170 exposed from the cathode portion 160 is placed on the second terminal piece. In addition, at least one capacitor element 170 is laminated on the first terminal piece and the second terminal piece.

  At this time, on the cathode portion 160 side, a conductive adhesive serving as the connection conductor layer 190 is interposed between the capacitor elements 170 adjacent to each other. Similarly, a conductive adhesive serving as the connection conductor layer 190 is interposed between the first terminal piece and the capacitor element 170 adjacent thereto. Thereby, the cathode part 160 of the some capacitor | condenser element 170 and the 1st terminal piece are electrically connected.

  After laminating the plurality of capacitor elements 170, one end of the metal layer 141 of the plurality of capacitor elements 170, the second terminal piece, and the like are electrically connected using welding or the like.

  Next, in step S23, at least one capacitor element 170 is molded using an insulating resin member. Specifically, the end side of the first terminal piece located on the side opposite to the second terminal piece side and the end side of the second terminal piece located on the side opposite to the first terminal piece side are exposed. One terminal piece, a second terminal piece, and at least one capacitor element are molded.

  More specifically, the first terminal piece, the second terminal piece, and the plurality of capacitor elements 170 are placed in the mold so that the end side of the first terminal piece and the end side of the second terminal piece are exposed. Accommodate. In addition, the said metal mold | die is arrange | positioned in the chamber.

  By reducing the pressure in the chamber or supplying an inert gas such as nitrogen or argon into the chamber, the chamber is under a low-saturated water vapor pressure environment with a dew point temperature of 5 ° C. or lower, and in a deoxygenated environment. And The deoxygenated environment is an environment in which the oxygen concentration is lower than the outside air outside the chamber.

  In this low saturated water vapor pressure environment and in a deoxygenated environment, an insulating resin such as an epoxy resin is filled in the mold. When the insulating resin is solidified, an insulating resin body 110 is formed, and a plurality of capacitor elements 170 are provided inside the insulating resin body 110.

  The mold is released, and the insulating resin body 110 in which the plurality of capacitor elements 170 are provided is taken out from the chamber. The first terminal 120 is formed by bending a portion of the first terminal piece protruding outward from the insulating resin body 110 along the first end surface 110e and the second main surface 110b. In addition, the second terminal 130 is formed by bending the second terminal piece protruding from the insulating resin body 110 along the second end surface 110f and the second main surface 110b.

  Through the steps as described above, the solid electrolytic capacitor 100 according to the first embodiment is manufactured.

  As described above, in the method for manufacturing solid electrolytic capacitor 100 according to the first embodiment, in the step of molding one or more capacitor elements, the dew point temperature is 5 ° C. or lower and the saturated water vapor pressure is low. At least one capacitor element is molded in an oxygen environment.

  As a result, the plurality of capacitor elements 170 can be molded in a low-humidity state in which the surroundings of the plurality of capacitor elements 170 contain moisture in an amount such that the dew point temperature is 5 ° C. or less, and in the low-oxygen state.

  For this reason, even if the gas remaining in the region R1 around the plurality of capacitor elements 170 enters the solid electrolyte layer 165, it is possible to suppress the progress of the dedoping of the conductive polymer due to moisture and oxygen. Can do. As a result, the solid electrolyte can suppress deterioration over time, and the reliability of the solid electrolytic capacitor 100 can be improved.

  In the solid electrolytic capacitor 100 according to the first embodiment described above, the periphery of the plurality of capacitor elements 170 is compared with the outside of the insulating resin body in a low-humidity state where the dew point temperature includes 5 ° C. or less of moisture. The case where the oxygen concentration is in a low oxygen state has been described as an example. However, the present invention is not limited to this and may be in one of a low humidity state and a low oxygen state.

  When the surroundings of the plurality of capacitor elements 170 provided in the insulating resin body 110 are in a low humidity state, the moisture enters the solid electrolyte layer 165, whereby the conductivity contained in the solid electrolyte layer 165 is reached. The dedoping of the conducting polymer can be suppressed. As a result, the solid electrolyte can suppress deterioration over time, and the reliability of the solid electrolytic capacitor 100 can be improved.

  In order to manufacture a solid electrolytic capacitor in which the periphery of the plurality of capacitor elements 170 provided inside the insulating resin body 110 is in a low humidity state, in the step of molding at least one capacitor element, A plurality of capacitor elements are molded in the saturated water vapor pressure environment.

  On the other hand, when the periphery of the plurality of capacitor elements 170 provided inside the insulating resin body 110 is in a low-oxygen state, oxygen enters the solid electrolyte layer 165 to enter the solid electrolyte layer 165. De-doping of the conductive polymer contained can be suppressed. As a result, the solid electrolyte can suppress deterioration over time, and the reliability of the solid electrolytic capacitor 100 can be improved.

  In order to manufacture the solid electrolytic capacitor in which the periphery of the plurality of capacitor elements 170 provided inside the insulating resin body 110 is in the low humidity state, at least one capacitor element is molded. Then, a plurality of capacitor elements are molded in a deoxygenated environment.

(Embodiment 2)
(Solid electrolytic capacitor)
FIG. 5 is a cross-sectional view showing the solid electrolytic capacitor according to the second embodiment. With reference to FIG. 5, a solid electrolytic capacitor 100A according to the second embodiment will be described.

  As shown in FIG. 5, the solid electrolytic capacitor 100 </ b> A according to the second embodiment is different from the solid electrolytic capacitor 100 according to the first embodiment in the configuration of the insulating resin body 110 </ b> A. Specifically, the insulating resin body 110 </ b> A includes a first insulating resin body 111 and a second insulating resin body 112.

  The first insulating resin body 111 has an uncovered region R <b> 2 that does not cover a part of the plurality of capacitor elements 170. In the second embodiment, the uncovered region R2 is a region that does not cover a part of the main surface on the one side of the first capacitor element 170a located on the most side in the stacking direction of the capacitor elements 170. The uncovered region R2 is provided so as to reach the one main surface of the first capacitor element 170a from the first main surface 110Aa of the insulating resin body 110A. The uncovered region R2 has a columnar shape.

  The uncovered region R2 may be a region that does not cover a part of the main surface on the other side of the second capacitor element 170b located on the other side in the stacking direction of the capacitor elements 170. In this case, the uncovered region R2 is provided so as to reach the other main surface of the second capacitor element 170b from the second main surface 110Ab of the insulating resin body 110A. Further, the non-covering region R2 may be provided so as to reach from the first end face 110Ae to the tip side of the cathode portion 160 of any one of the plurality of capacitor elements 170. Further, the non-covering region R2 may be provided so as to reach the one end side of the metal layer 141 exposed from the cathode portion 160 from the second end face 110Af.

  The first insulating resin body 111 is made of substantially the same material as the insulating resin body 110 according to the first embodiment.

  The second insulating resin body 112 is filled in the uncovered region R2 and covers the part of the plurality of capacitor elements 170 that are not covered by the first insulating resin body 111. The second insulating resin body 112 may be configured by the same member as the first insulating resin body 111 or may be configured by a different member.

  The second insulating resin body 112 is made of a low-permeability resin having low oxygen and water vapor permeability. As the low-permeability resin, for example, an epoxy resin, a phenol resin, and a furan resin can be employed.

  Even in this case, the region R1 around the plurality of capacitor elements 170 provided in the insulating resin body 110A is in a low humidity state including an amount of water that has a dew point temperature of 5 ° C. or lower, and is in the low oxygen state. ing.

  As a result, even in the solid electrolytic capacitor 100A according to the second embodiment, the solid electrolyte layer can suppress deterioration over time as in the solid electrolytic capacitor 100 according to the first embodiment. Reliability can be improved.

(Method for manufacturing solid electrolytic capacitor)
FIG. 6 is a diagram showing a manufacturing flow of the solid electrolytic capacitor according to the second embodiment. With reference to FIG. 6, a method of manufacturing solid electrolytic capacitor 100A according to the second embodiment will be described.

  As shown in FIG. 6, the method for manufacturing solid electrolytic capacitor 100 </ b> A according to the second embodiment has an insulating resin body that includes at least one capacitor element as compared with the method for manufacturing solid electrolytic capacitor 100 according to the first embodiment. The process S20A provided in the inside is different.

  When manufacturing the solid electrolytic capacitor 100A, at least one capacitor element 170 is prepared in step S10 as in the first embodiment. Specifically, a plurality of metal layers 141 are prepared, and steps S11 to S14 are performed as in the first embodiment.

  Next, at step S20A, at least one capacitor element 170 is provided inside the insulating resin body 110A. In the second embodiment, a plurality of capacitor elements 170 are provided inside insulating resin body 110A. Specifically, the following steps S21 to S23A are performed.

  First, as in the first embodiment, step S21 and step S22 are performed. Next, in step S23A, at least one capacitor element 170 is molded using an insulating resin member. In this case, a plurality of capacitor elements 170 are molded.

  When molding a plurality of capacitor elements 170, first, in step S231, a first insulating resin having an uncovered region that does not cover at least a part of at least one capacitor element 170 using the first resin material. A body 111 is formed.

  Specifically, the first terminal piece, the second terminal piece, and the plurality of capacitor elements 170 are accommodated in the mold so that the end side of the first terminal piece and the end side of the second terminal piece are exposed. To do. The said metal mold | die contains a 1st metal mold | die, a 2nd metal mold | die, and a 3rd metal mold | die, for example.

  The first mold defines the first insulating resin body 111 that covers the capacitor element 170 laminated on one side of the capacitor element 170 in the lamination direction with respect to the first terminal piece and the second terminal piece. Is. The second mold defines the first insulating resin body 111 that covers the capacitor element 170 laminated on the other side of the capacitor element 170 in the lamination direction with respect to the first terminal piece and the second terminal piece. Is. The third mold includes a portion having a shape corresponding to the non-covering region R2, and defines a region where the non-covering region R2 is not filled with a first resin material to be described later. The third mold abuts on the first capacitor element 170a located on the most side in the stacking direction.

  The first mold, the second mold, and the third mold are provided independently of each other and are configured to be able to be released from the mold. A mold constituted by the first mold, the second mold, and the third mold is disposed in the chamber.

  The mold is filled with a first resin material such as an epoxy resin in an environment substantially the same as that outside the chamber. When the first resin material is solidified, the first insulating resin body 111 having the uncovered region R2 is formed.

  Next, the third mold is released. Thereby, a part of the cathode portion 160 of the first capacitor element 170a located on the most one side is exposed. Thereby, the minute space formed around the plurality of capacitor elements 170 and the inside of the chamber communicate with each other through the non-covering region R2.

  Next, in step S232, an inert gas is supplied around at least one or more capacitor elements via the non-covering region R2. Specifically, an inert gas such as nitrogen and argon is introduced into the chamber. As a result, the inert gas is supplied around the plurality of capacitor elements 170 via the uncovered region R2. As a result, the periphery of the plurality of capacitor elements 170 is in a low-humidity state that includes an amount of water that has a dew point temperature of 5 ° C. or lower, and the low-oxygen state.

  Next, in step S233, the non-covering region R2 is sealed with the second resin material. Specifically, a second resin material such as an epoxy resin is filled in the non-covering region R2 with an inert gas introduced into the chamber. The second insulating resin body 112 is formed by curing the second resin material.

  As a result, the plurality of capacitor elements 170 are covered with the first insulating resin body 111 and the second insulating resin body 112, and the plurality of capacitor elements 170 are provided inside the insulating resin body 110A.

  Next, the first mold and the second mold are released, and the insulating resin body 110A provided with the plurality of capacitor elements 170 is taken out from the chamber. The first terminal 120 and the second terminal 130 are formed by bending the portions of the first terminal piece and the second terminal piece that protrude outward from the insulating resin body 110A.

  Through the steps as described above, solid electrolytic capacitor 100A according to Embodiment 1 is manufactured.

  Even in the case of manufacturing using the manufacturing method of the solid electrolytic capacitor 100A according to the second embodiment, a low-humidity state in which the surroundings of the plurality of capacitor elements 170 include water in an amount such that the dew point temperature is 5 ° C. or lower, and the above A plurality of capacitor elements 170 can be molded in a low oxygen state. As a result, as in the first embodiment, the solid electrolyte can suppress deterioration over time, and the reliability of the solid electrolytic capacitor 100 can be improved.

(Embodiment 3)
(Solid electrolytic capacitor)
FIG. 7 is a perspective view showing a solid electrolytic capacitor according to the third embodiment. 8 is a cross-sectional view taken along line VIII-VIII shown in FIG. FIG. 9 is a cross-sectional view taken along line IX-IX shown in FIG. A solid electrolytic capacitor 100B according to Embodiment 3 will be described with reference to FIGS.

  As shown in FIGS. 7 to 9, the solid electrolytic capacitor 100B according to Embodiment 3 has a substantially rectangular parallelepiped outer shape. The solid electrolytic capacitor 100B has a substantially rectangular parallelepiped outer shape. In the present embodiment, the outer dimensions of the solid electrolytic capacitor 100B are, for example, a dimension in the length direction L of 3.5 mm, a dimension in the width direction W of 2.8 mm, and a dimension in the height direction T of 1.9 mm.

  The solid electrolytic capacitor 100B includes a plurality of capacitor elements 170B, an insulating resin body 110, a lead conductor layer 180, a first external electrode 120B, and a second external electrode 130B.

  A plurality of capacitor elements 170 </ b> B and lead conductor layers 180 are embedded in the insulating resin body 110. The insulating resin body 110 has a substantially rectangular parallelepiped outer shape. The insulating resin body 110 includes a first main surface 110a and a second main surface 110b opposed in the height direction T, a first side surface 110c and a second side surface 110d opposed in the width direction W, and a relative relationship in the length direction L. A first end face 110e and a second end face 110f.

  As described above, the insulating resin body 110 has a substantially rectangular parallelepiped outer shape, but the corner portions and the ridge line portions are rounded. The corner portion is a portion where three surfaces of the insulating resin body 110 intersect, and the ridge line portion is a portion where two surfaces of the insulating resin body 110 intersect. Irregularities may be formed on at least one of the first main surface 110a, the second main surface 110b, the first side surface 110c, the second side surface 110d, the first end surface 110e, and the second end surface 110f.

  The insulating resin body 110 includes a first insulating resin body 111 and a second insulating resin body 112. The first insulating resin body 111 has a mold part 111a and a substrate 111b. The substrate 111b is made of an insulating resin substrate such as a glass epoxy substrate. The substrate 111b is made of a composite material such as FRP (Fiber Reinforced Plastics). As a material constituting the substrate 111b, a composite material in which a woven fabric or a nonwoven fabric made of carbon, glass, silica, or the like is placed in an insulating resin such as an epoxy resin can be used. The thickness of the substrate 111b is, for example, 100 μm.

  Mold part 111a seals most of a plurality of capacitor elements 170B on substrate 111b. The mold part 111a has an uncovered region R2. The uncovered region R2 is a region that does not cover a part of the main surface on the one side of the first capacitor element 170a located on the most side in the stacking direction of the capacitor elements 170B. The uncovered region R2 is provided so as to reach the main surface on one side of the first capacitor element 170a from the first main surface 110a of the insulating resin body 110. The uncovered region R2 has a columnar shape.

  The mold part 111a is composed of substantially the same member as the insulating resin body 110 according to the first embodiment.

  A plurality of conductive particles exist on each of the first end face 110e and the second end face 110f of the insulating resin body 110. The conductive particles contain Pd. The surface roughness (Ra) of each of the first end surface 110e and the second end surface 110f of the insulating resin body 110 is preferably 2.2 μm or more and 8.3 μm or less.

  The hardness of the mold part 111a is lower than the hardness of the substrate 111b. Therefore, at the corner of the insulating resin body 110, the corner of the mold portion 111a is rounder than the corner of the substrate 111b.

  The plurality of capacitor elements 170B are sealed with the mold part 111a and the second insulating resin body 112 on the substrate 111b.

  Each of the plurality of capacitor elements 170B includes an anode portion 140, a dielectric layer 150, a solid electrolyte layer 165, and a cathode portion 160. Capacitor element 170B differs from capacitor element 170 according to Embodiment 1 in the configuration of anode portion 140. Other configurations are almost the same.

  The anode part 140 includes a metal layer 141 extending in the length direction L. The anode part 140 further includes a first plating film 142 and a second plating film 143 provided on the metal layer 141.

  The end surface of the metal layer 141 near the second end surface 110 f is covered with the first plating film 142. The first plating film 142 is covered with the second plating film 143. The first plating film 142 contains Zn. The second plating film 143 contains Ni. Note that the first plating film 142 and the second plating film 143 are not necessarily provided.

  The insulating layer 151 covers the outer surface of the metal layer 141 from the position adjacent to the portion where the solid electrolyte layer 165 is provided to the end of the anode portion 140 near the second end face 110f. The length of the insulating layer 151 in the length direction L is preferably 0.025 to 0.5 times the length of the insulating resin body 110 in the length direction L. The thickness of the insulating layer 151 is preferably 5 μm or more and 30 μm or less.

  The plurality of capacitor elements 170B are stacked in the height direction T on the substrate 111b. The extending direction of each of the plurality of capacitor elements 170B is substantially parallel to the main surface of the substrate 111b.

  The current collector layers of the capacitor elements 170B adjacent to each other are connected to each other by the connection conductor layer 190. The width of the connection conductor layer 190 in the width direction W is equal to the width of the metal layer 141 in the width direction W.

  The lead conductor layer 180 is provided on the substrate 111 b that is a part of the insulating resin body 110. The lead conductor layer 180 is located closer to the second main surface 110 b inside the insulating resin body 110. The width of the lead conductor layer 180 in the width direction W is equal to the width of the metal layer 141 in the width direction W.

  The length of the lead conductor layer 180 in the length direction L is preferably not less than 0.3 times and not more than 0.8 times the length of the insulating resin body 110 in the length direction L. The thickness of the lead conductor layer 180 is preferably 10 μm or more and 100 μm or less.

  In the portion where the lead conductor layer 180 and the connection conductor layer 190 are connected, the distance in the length direction L between the position closest to the first end surface 110e and the first end surface 110e is 87.5 μm or more and 1750 μm or less. Preferably there is.

  The lead conductor layer 180 contains Cu. In the present embodiment, the end surface of the lead conductor layer 180 near the first end surface 110 e is covered with the third plating film 181. The third plating film 181 contains Ni. Note that the third plating film 181 is not necessarily provided.

  The lead conductor layer 180 is connected to the current collector layer of one capacitor element 170B among the plurality of capacitor elements 170B. Specifically, among the plurality of capacitor elements 170 </ b> B, the capacitor element 170 </ b> B located at the end closest to the second main surface 110 b in the height direction T is adjacent to the lead conductor layer 180. The current collector layer of only the capacitor element 170 B adjacent to the lead conductor layer 180 is connected to the lead conductor layer 180 by the connection conductor layer 190.

  The first external electrode 120 </ b> B is provided on the first end face 110 e of the insulating resin body 110. Specifically, the first external electrode 120B extends from the first end surface 110e of the insulating resin body 110 to each of the first main surface 110a, the second main surface 110b, the first side surface 110c, and the second side surface 110d. Is provided. The first external electrode 120B is electrically connected to each cathode portion 160 of the plurality of capacitor elements 170B.

  The first external electrode 120 </ b> B is composed of at least one plating layer provided on the first end face 110 e of the insulating resin body 110. In the present embodiment, the first external electrode 120 </ b> B includes a first plating layer 121 provided on the first end surface 110 e of the insulating resin body 110 and a second plating layer 122 provided on the first plating layer 121. And a third plating layer 123 provided on the second plating layer 122. The first plating layer 121 contains Cu. The second plating layer 122 contains Ni. The third plating layer 123 contains Sn.

  The first external electrode 120B is directly or indirectly connected to the lead conductor layer 180 at the first end face 110e of the insulating resin body 110. The first external electrode 120B is connected to the lead conductor layer 180 with the third plating film 181 interposed therebetween. That is, the third plating film 181 is provided between the first external electrode 120 </ b> B and the lead conductor layer 180.

  The second external electrode 130 </ b> B is provided on the second end surface 110 f of the insulating resin body 110. Specifically, the second external electrode 130B extends from the second end surface 110f of the insulating resin body 110 to each of the first main surface 110a, the second main surface 110b, the first side surface 110c, and the second side surface 110d. Is provided. The second external electrode 130B is electrically connected to the anode part 140 of each of the plurality of capacitor elements 170B.

  The second external electrode 130 </ b> B is composed of at least one plating layer provided on the second end surface 110 f of the insulating resin body 110. The second external electrode 130B includes a first plating layer 131 provided on the second end face 110f of the insulating resin body 110, a second plating layer 132 provided on the first plating layer 131, and a second plating layer. And a third plating layer 133 provided on 132. The first plating layer 131 contains Cu. The second plating layer 132 contains Ni. The third plating layer 133 contains Sn.

  The second external electrode 130B is directly or indirectly connected to each metal layer 141 of the plurality of capacitor elements 170B on the second end face 110f of the insulating resin body 110. The second external electrode 130B is connected to the metal layer 141 of each of the plurality of capacitor elements 170B with the first plating film 142 and the second plating film 143 interposed therebetween. That is, the first plating film 142 and the second plating film 143 are provided between the metal layer 141 and the second external electrode 130B of each of the plurality of capacitor elements 170B.

  Even in this case, the region R1 around the plurality of capacitor elements 170B provided in the insulating resin body 110 is in a low-humidity state containing water in an amount that causes a dew point temperature of 5 ° C. or lower, and is in the low-oxygen state. ing.

  Thereby, even in the solid electrolytic capacitor 100B according to the third embodiment, the solid electrolyte layer can suppress deterioration over time as in the solid electrolytic capacitor 100 according to the first embodiment, and the solid electrolytic capacitor 100B. Reliability can be improved.

  Further, in the solid electrolytic capacitor 100B according to the third embodiment, when compared with the solid electrolytic capacitor 100 according to the first embodiment, the first terminal and the second terminal protrude from the insulating resin body to the outside. It is not provided, and external electrodes are provided on the first end face and the second end face of the insulating resin. In addition, one end side of the metal layer 141 exposed from the cathode side is connected to the second external electrode. By having such a configuration, the outer shape of the solid electrolytic capacitor can be reduced.

(Method for manufacturing solid electrolytic capacitor)
FIG. 10 is a diagram showing a manufacturing flow of the solid electrolytic capacitor according to the third embodiment. With reference to FIG. 10, the manufacturing method of the solid electrolytic capacitor 100B which concerns on Embodiment 3 is demonstrated.

  As shown in FIG. 10, the method for manufacturing solid electrolytic capacitor 100 </ b> B according to the third embodiment includes at least one capacitor element as an insulating resin body as compared with the method for manufacturing solid electrolytic capacitor 100 according to the first embodiment. The difference is that the step S20B provided inside is different, and further includes steps S31 to S35 described later.

  When manufacturing the solid electrolytic capacitor 100B, at least one capacitor element 170B is prepared in step S10 as in the first embodiment. Specifically, a plurality of metal layers 141 are prepared, and steps S11 to S14 are performed as in the first embodiment.

  Next, in step S20B, at least one capacitor element 170B is provided inside the insulating resin body 110. In the third embodiment, a plurality of capacitor elements 170B are provided inside insulating resin body 110. Specifically, the following steps S21B to S23B are performed.

  First, in step S21B, at least one or more capacitor elements are stacked on the substrate 111b. Specifically, a plurality of capacitor elements 170B are stacked on the substrate 111b on which the lead conductor layer 180 is provided. At this time, the current collector layer of the capacitor element 170B and the lead conductor layer 180 are connected by a conductive adhesive such as Ag paste, and the current collector layers of the capacitor elements 170B adjacent to each other are connected. The lead conductor layer 180 is blackened. Subsequently, the substrate 111b and the capacitor element 170B are thermocompression bonded. The conductive adhesive heated and cured becomes the connection conductor layer 190.

  Next, in step S23B, at least one capacitor element is molded using an insulating resin member. In this case, a plurality of capacitor elements 170B are molded.

  When molding a plurality of capacitor elements 170B, first, in step S231, a first insulating resin having a non-covered region that does not cover at least a part of at least one capacitor element 170B using the first resin material. A body 111 is formed.

  Specifically, a substrate 111b on which a plurality of capacitor elements 170B are stacked is housed in a mold. The said metal mold | die contains a 1st metal mold | die, a 2nd metal mold | die, and a 3rd metal mold | die, for example.

  The first mold defines the first insulating resin body 111 that covers the capacitor element 170B far from the substrate 111b in the stacking direction of the plurality of capacitor elements 170B. The second mold defines the first insulating resin body 111 that covers the capacitor element 170B on the side closer to the substrate 111b in the stacking direction of the plurality of capacitor elements 170B. The second mold is configured to be in close contact with the outer surface of the substrate 111b so that the first resin material does not enter between the substrate 111b and the second mold. The third mold includes a portion having a shape corresponding to the non-covering region R2, and defines a region where the non-covering region R2 is not filled with a first resin material to be described later. The third mold abuts on the first capacitor element 170a located on the most side in the stacking direction.

  The first mold, the second mold, and the third mold are provided independently of each other and are configured to be able to be released from the mold. A mold constituted by the first mold, the second mold, and the third mold is disposed in the chamber.

  The mold is filled with a first resin material such as an epoxy resin in an environment substantially the same as that outside the chamber. When the first resin material is solidified, a mold part 111a having an uncovered region R2 is formed on the substrate 111b.

  Next, the third mold is released. Thereby, a part of the cathode portion 160 of the first capacitor element 170a located on the most one side is exposed. Thereby, the minute space formed around the plurality of capacitor elements 170B and the inside of the chamber communicate with each other through the non-covering region R2.

  Next, in step S232, an inert gas is supplied around at least one or more capacitor elements via the non-covering region R2. Specifically, an inert gas such as nitrogen and argon is introduced into the chamber. As a result, the inert gas is supplied around the plurality of capacitor elements 170B through the non-covering region R2. As a result, the surroundings of the plurality of capacitor elements 170B are in a low-humidity state that includes an amount of water that has a dew point temperature of 5 ° C. or lower, and the low oxygen state.

  Next, in step S233, the non-covering region R2 is sealed with the second resin material. Specifically, a second resin material such as an epoxy resin is filled in the non-covering region R2 with an inert gas introduced into the chamber. The second insulating resin body 112 is formed by curing the second resin material.

  Next, in step S31, the substrate 111b and the capacitor element 170B are cut so as to divide the masking portion formed in step S12. Specifically, the molded substrate 111b and the capacitor element 170B are cut by pressing, dicing, or laser cutting. By this step, a chip including the insulating resin body 110 is formed.

  Next, in step S32, the chip is barrel-polished. Specifically, the chip is sealed together with an abrasive in a small box called a barrel, and the chip is polished by rotating the barrel. Thereby, the corner | angular part and ridgeline part of a chip | tip are rounded.

  Next, in step S33, the end surface of the metal layer 141 exposed on the end surface of the chip is plated. Specifically, the oil content of the chip is removed with an alkali treatment agent. By performing alkali etching, the oxide film on the end face of the metal layer 141 is removed. The smut on the end surface of the metal layer 141 is removed by the smut removing process. A first plating film 142 is formed on the end surface of the metal layer 141 by substitution deposition of Zn by a zincate process. A second plating film 143 is formed on the first plating film 142 by electroless Ni plating. At this time, the third plating film 181 is formed on the end surface of the lead conductor layer 180.

  Next, in step S34, a liquid imparting conductivity is attached to both ends of the chip. Specifically, portions other than the both ends of the chip are masked. In order to improve the wettability of the liquid that imparts conductivity to the surfaces of both ends of the chip and to make the conductive particles contained in the liquid that imparts conductivity easily adsorbed to both ends of the chip, a surfactant is used. Degrease the chip. As a conditioner having degreasing power, any one of anionic, cationic, amphoteric and nonionic surfactants is selected and used in accordance with the type of liquid imparting conductivity.

  In the third embodiment, the conductive particles contained in the liquid imparting conductivity contain Pd as a catalytic metal serving as a nucleus of plating. However, the present invention is not limited to this. From Pd, Sn, Ag, and Cu What is necessary is just to contain the at least 1 sort (s) of metal selected from the group which consists of. The liquid imparting conductivity is a solution containing the above metal ions or a colloidal solution of the above metal.

  The chip on which the liquid imparting conductivity is attached to both ends is washed with water or a solvent and then dried to form conductive films on both ends of the chip. As a result, a plurality of conductive particles are present on each of the first end surface 110e and the second end surface 110f of the insulating resin body 110. The surface of both ends of the chip is roughened by microetching the chip having the conductive film formed at both ends.

  Next, in step S35, the first external electrode 120B and the second external electrode 130B are formed by plating on both ends of the chip. Specifically, a first plating layer 131 containing Cu is formed on the conductive films at both ends of the chip by electrolytic plating. The first plating layer 131 is formed using conductive particles attached to both ends of the chip as nuclei. A second plating layer 132 containing Ni is formed on the first plating layer 131 by electrolytic plating. A third plating layer 133 containing Sn is formed on the second plating layer 132 by electrolytic plating.

  Through the steps as described above, solid electrolytic capacitor 100B according to Embodiment 3 is manufactured.

  Even in the case where the solid electrolytic capacitor 100B according to the third embodiment is manufactured using the method for manufacturing the solid electrolytic capacitor 100B, the surroundings of the plurality of capacitor elements 170B include a low humidity state including an amount of water that has a dew point temperature of 5 ° C. or lower, and the above A plurality of capacitor elements 170B can be molded in a low oxygen state. As a result, as in the first embodiment, the solid electrolyte can suppress deterioration over time, and the reliability of the solid electrolytic capacitor 100 can be improved.

  In Embodiment 3 mentioned above, the mold part 111a of the 1st insulating resin body 111 has the non-covering area | region R2, and illustrates the structure by which the 2nd insulating resin body 112 is filled into the said non-covering area | region R2. However, the present invention is not limited to this, and the mold portion 111a may not have the non-covering region R2 and the second insulating resin body 112 may not be provided. That is, the insulating resin body 110 may be constituted by the first insulating resin body 111 including the mold part 111a and the substrate 111b.

  In this case, in the method for manufacturing the solid electrolytic capacitor, in step S231, the first resin member is used to mold the plurality of capacitor elements 170 on the substrate 111b so that the uncovered region R2 is not formed. Steps S232 and S233 are omitted. When molding a plurality of capacitor elements 170 on the substrate 111b so that the uncovered region R2 is not formed, the inside of the chamber is depressurized or an inert gas such as nitrogen or argon is supplied into the chamber. Thus, the inside of the chamber is placed in a low saturated water vapor pressure environment where the dew point temperature is 5 ° C. or lower and in a deoxygenated environment. Note that the plurality of capacitor elements 170 may be molded in either one of a low saturated water vapor pressure environment and a deoxygenated environment.

  In the method for manufacturing the solid electrolytic capacitor according to the above-described second and third embodiments, the first mold and the second mold are not released, and only the third mold is released. The case where the second resin material is filled in the non-covering region R2 has been described as an example. However, the present invention is not limited to this, and the second resin material is used in a state where the third mold is completely released from the first mold. The uncovered region R2 may be filled.

  Further, in the method for manufacturing the solid electrolytic capacitor according to the above-described second and third embodiments, the case where steps S231 to S233 are performed in the same chamber has been described as an example. However, each step is performed in different chambers. You may go on.

  In the first to third embodiments described above, the case where a plurality of capacitor elements 170 are provided inside the insulating resin body has been described as an example. However, the present invention is not limited to this, and one capacitor element 170 is provided. May be provided inside.

  Although the embodiments of the present invention have been described above, the embodiments disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is defined by the terms of the claims, and includes meanings equivalent to the terms of the claims and all modifications within the scope.

  100, 100A, 100B solid electrolytic capacitor, 110, 110A insulating resin body, 110a first main surface, 110b second main surface, 110c first side surface, 110d second side surface, 110e first end surface, 110f second end surface, 111 1st insulating resin body, 111a mold part, 111b substrate, 112 2nd insulating resin body, 120 1st terminal, 120B 1st external electrode, 121 1st plating layer, 122 2nd plating layer, 123 3rd plating layer , 130 second terminal, 130B second external electrode, 131 first plating layer, 132 second plating layer, 133 third plating layer, 140 anode part, 141 metal layer, 142 first plating film, 143 second plating film, 150 Dielectric layer, 151 Insulating layer, 160 Cathode portion, 161 First current collector layer, 162 Second current collector layer, 165 Solid Electrolyte layer, 170, 170B capacitor element, 170a first capacitor element, 170b second capacitor element, 180 lead conductor layer, 181 third plated film, 190 connecting conductor layer.

Claims (12)

Having an outer surface provided with a plurality of recesses, an anode part made of a metal layer, a dielectric layer provided on the outer surface of the metal layer, provided on at least a part of the outer surface of the dielectric layer; At least one capacitor element including a solid electrolyte layer having a conductive polymer, and a cathode portion having a current collector layer provided on an outer surface of the solid electrolyte layer;
An insulating resin body in which the at least one capacitor element is provided, and
A solid electrolytic capacitor in which the periphery of the at least one capacitor element is in a low-humidity state including an amount of water that has a dew point temperature of 5 ° C. or less. Having an outer surface provided with a plurality of recesses, an anode part made of a metal layer, a dielectric layer provided on the outer surface of the metal layer, provided on at least a part of the outer surface of the dielectric layer; At least one capacitor element including a solid electrolyte layer having a conductive polymer, and a cathode portion having a current collector layer provided on an outer surface of the solid electrolyte layer;
An insulating resin body in which the at least one capacitor element is provided, and
The solid electrolytic capacitor in which the periphery of the at least one capacitor element is in a low oxygen state as compared with the outside of the insulating resin body.   The solid electrolytic capacitor according to claim 2, wherein a periphery of the at least one capacitor element is in a low-humidity state including moisture in an amount that causes a dew point temperature of 5 ° C. or less. A first terminal electrically connected to the cathode portion inside the insulating resin body and drawn out of the insulating resin body;
4. The apparatus according to claim 1, further comprising: a second terminal that is electrically connected to the anode portion inside the insulating resin body and drawn out of the insulating resin body. The solid electrolytic capacitor as described. A lead conductor layer connected to the current collector layer;
A first external electrode electrically connected to the cathode portion through the lead conductor layer;
A second external electrode electrically connected to the anode part,
The insulating resin body has a first end surface and a second end surface facing in the extending direction of the metal layer,
The first external electrode is provided on the first end surface,
The second external electrode is provided on the second end surface,
The lead conductor layer is drawn to the first end face side and connected to the first external electrode;
4. The solid according to claim 1, wherein one end side of the metal layer exposed from the cathode portion is drawn out to the second end face side and connected to the second external electrode. Electrolytic capacitor.   The insulating resin body includes a first insulating resin body having a non-covered region that does not cover a part of the at least one capacitor element; and the at least one capacitor is filled in the non-covered region. The solid electrolytic capacitor according to claim 1, further comprising a second insulating resin body that covers the part of the element. Having an outer surface provided with a plurality of recesses, an anode part made of a metal layer, a dielectric layer provided on the outer surface of the metal layer, provided on at least a part of the outer surface of the dielectric layer; Preparing at least one capacitor element including a solid electrolyte layer having a conductive polymer and a cathode portion having a current collector layer provided on an outer surface of the solid electrolyte layer;
Providing the at least one capacitor element inside an insulating resin body,
The step of providing the at least one capacitor element inside the insulating resin body includes a step of molding the at least one capacitor element using an insulating resin member,
A method for producing a solid electrolytic capacitor, wherein in the step of molding the at least one capacitor element, the at least one capacitor element is molded under a low saturated water vapor pressure at which a dew point temperature is 5 ° C. or less. Having an outer surface provided with a plurality of recesses, an anode part made of a metal layer, a dielectric layer provided on the outer surface of the metal layer, provided on at least a part of the outer surface of the dielectric layer; Preparing at least one capacitor element including a solid electrolyte layer having a conductive polymer and a cathode portion having a current collector layer provided on an outer surface of the solid electrolyte layer;
Providing the at least one capacitor element inside an insulating resin body,
The step of providing the at least one capacitor element inside the insulating resin body includes a step of molding the at least one capacitor element using an insulating resin member,
A method for producing a solid electrolytic capacitor, wherein in the step of molding the at least one capacitor element, the at least one capacitor element is molded in a deoxygenated environment.   The solid electrolytic capacitor according to claim 8, wherein in the step of molding the at least one capacitor element, the at least one capacitor element is molded under a low saturated water vapor pressure with a dew point temperature of 5 ° C. or less. Production method. Having an outer surface provided with a plurality of recesses, an anode part made of a metal layer, a dielectric layer provided on the outer surface of the metal layer, provided on at least a part of the outer surface of the dielectric layer; Preparing at least one capacitor element including a solid electrolyte layer having a conductive polymer and a cathode portion having a current collector layer provided on an outer surface of the solid electrolyte layer;
Providing the at least one capacitor element inside an insulating resin body,
The step of providing the at least one capacitor element inside the insulating resin body includes a step of molding the at least one capacitor element using an insulating resin member,
The step of molding the at least one capacitor element uses a first resin material to form a first insulating resin body having an uncovered region that does not cover a part of the at least one capacitor element. A step of supplying an inert gas around the at least one capacitor element through the non-covered region, and a step of sealing the non-covered region with a second resin material. The manufacturing method of a solid electrolytic capacitor. The step of providing the at least one capacitor element inside the insulating resin body includes a step of arranging the first terminal piece and the second terminal piece in a straight line in a state of being separated from each other, and the cathode portion of the capacitor element. The first terminal piece and the first terminal piece are placed on the first terminal piece, and the metal layer of the capacitor element exposed from the cathode portion is placed on the second terminal piece. Laminating the at least one capacitor element on a two-terminal piece, and
In the step of molding the at least one capacitor element, the first terminal piece is located on the side opposite to the second terminal piece side and the first terminal piece side is located on the opposite side of the first terminal piece side. The said 1st terminal piece, the said 2nd terminal piece, and the said at least 1 or more capacitor | condenser element are molded so that the edge part side of 2 terminal pieces may be exposed. A method for producing a solid electrolytic capacitor. The step of providing the at least one capacitor element inside the insulating resin body further includes the step of laminating the at least one capacitor element on the insulating resin substrate,
The solid electrolysis according to any one of claims 7 to 10, wherein in the step of molding the at least one capacitor element, the at least one capacitor element is molded on the insulating resin substrate. Capacitor manufacturing method.

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