JP2021097165A - Solid electrolytic capacitor - Google Patents

Abstract

To provide a solid electrolytic capacitor which is little in change of ESR due to thermal stress.SOLUTION: A solid electrolytic capacitor 1 includes a resin molding 9, a first external electrode 11, and a second external electrode 13. The resin molding includes a laminate 30 in which a plurality of capacitor elements are laminated, and a sealing resin 8 sealing the periphery of the laminate. The capacitor element includes an anode 3 having a dielectric layer 5 thereon, and a cathode 7 opposite to the anode through the dielectric layer. In the first external electrode, a non-contact region 41 where a cathode of the one capacitor element and a cathode of the other capacitor element are not brought into contact with each other, and a contact region 42 that surrounds the non-contact region and where the cathode of the one capacitor element and the cathode of the other capacitor element are brought into contact with each other are present between at least one set of adjacent capacitor elements in a lamination direction.SELECTED DRAWING: Figure 2

Description

The present invention relates to a solid electrolytic capacitor.

The solid electrolytic capacitor includes a valve acting metal substrate having a dielectric layer on the surface of a substrate made of a valve acting metal such as aluminum, and a cathode layer including a solid electrolyte layer provided on the dielectric layer.

For example, Patent Document 1 describes (A) a step of preparing a valve acting metal substrate having a dielectric layer formed on its surface and a first sheet having a solid electrolyte layer provided on the dielectric layer. B) A step of preparing a second sheet made of a metal foil, (C) a step of coating the first sheet with an insulating material, and (D) a conductor layer on the solid electrolyte layer of the first sheet. (E) A step of laminating the first sheet and the second sheet to prepare a laminated sheet, and (F) filling a through hole of the laminated sheet with a sealing material to form a laminated block. It includes a step of manufacturing a body, (G) a step of manufacturing a plurality of element laminated bodies by cutting a laminated block body, and (H) a step of forming a first external electrode and a second external electrode. A method for manufacturing a solid electrolytic capacitor is disclosed.

JP-A-2019-79866

According to Patent Document 1, a plurality of element laminates are produced by cutting a laminate obtained by laminating a first sheet and a second sheet, and an external electrode is formed on the element laminate. It is said that a plurality of solid electrolytic capacitors can be efficiently manufactured.

However, when a solid electrolytic capacitor in which a plurality of capacitor elements are laminated is heated by a heat treatment such as reflow, a large thermal stress is applied to the bottom surface side of the solid electrolytic capacitor, and a thermal stress is also applied to the upper surface side of the solid electrolytic capacitor. Join. As a result, there arises a problem that the laminated capacitor elements are peeled off and the equivalent series resistance (ESR) changes.

In particular, in a solid electrolytic capacitor in which a plurality of capacitor elements are laminated on a substrate made of glass epoxy resin or the like, the capacitor elements are easily peeled off due to a large warp of the substrate, so that the above problem becomes remarkable.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a solid electrolytic capacitor in which the change in ESR due to thermal stress is small.

The solid electrolytic capacitor of the present invention includes a resin molded body, a first external electrode, and a second external electrode. The resin molded body includes a laminated body in which a plurality of capacitor elements are laminated, and a sealing resin that seals the periphery of the laminated body. The resin molded body has a bottom surface and an upper surface facing the thickness direction parallel to the stacking direction of the capacitor elements, a first end surface and a second end surface facing the length direction orthogonal to the stacking direction, and the stacking direction. And has a first side surface and a second side surface which are opposite to each other in the width direction orthogonal to the length direction. The first external electrode is provided on the first end surface of the resin molded product. The second external electrode is provided on the second end surface of the resin molded product. The capacitor element includes an anode having a dielectric layer on its surface and a cathode facing the anode via the dielectric layer. The anode includes a valve acting metal substrate having a porous portion on the surface of the core portion. The cathode includes a cathode lead-out layer. The first external electrode is electrically connected to the valve acting metal substrate exposed from the first end surface. The second external electrode is electrically connected to the cathode lead-out layer exposed from the second end surface. Between at least one set of capacitor elements adjacent to each other in the stacking direction, a non-contact region in which the cathode of one capacitor element and the cathode of the other capacitor element do not contact and the non-contact region are surrounded by one capacitor element. There is a contact region where the cathode of the capacitor and the cathode of the other capacitor element come into contact with each other.

According to the present invention, it is possible to provide a solid electrolytic capacitor in which the change in ESR due to thermal stress is small.

FIG. 1 is a perspective view schematically showing an example of the solid electrolytic capacitor of the present invention. FIG. 2 is a cross-sectional view taken along the line II-II of the solid electrolytic capacitor shown in FIG. FIG. 3 is a plan view of the resin molded product shown in FIG. 2 as viewed from the thickness direction. FIG. 4 is a cross-sectional view schematically showing another example of the solid electrolytic capacitor of the present invention.

Hereinafter, the solid electrolytic capacitor of the present invention will be described.
However, the present invention is not limited to the following configurations, and can be appropriately modified and applied without changing the gist of the present invention. It should be noted that a combination of two or more desirable configurations of each embodiment described below is also the present invention.

[Solid electrolytic capacitor]
FIG. 1 is a perspective view schematically showing an example of the solid electrolytic capacitor of the present invention.
The solid electrolytic capacitor 1 shown in FIG. 1 is a surface mount type solid electrolytic capacitor, and includes a resin molded body 9, a first external electrode 11, and a second external electrode 13.

The resin molded body 9 has a rectangular parallelepiped shape. The resin molded body 9 has a first end surface 9a and a second end surface 9b facing the length direction (L direction), a bottom surface 9c and a top surface 9d facing the thickness direction (T direction), and a width direction (W direction). It has a first side surface 9e and a second side surface 9f facing each other. Here, the length direction, the width direction, and the thickness direction are orthogonal to each other.

The first end surface 9a is provided with the first external electrode 11, and the second end surface 9b is provided with the second external electrode 13.

The bottom surface 9c is a surface on the side that becomes the mounting surface of the solid electrolytic capacitor 1.

In the present specification, the surface of the solid electrolytic capacitor or the resin molded product along the length direction and the thickness direction is referred to as an LT surface, and the surface along the length direction and the width direction is referred to as an LW surface, and is referred to as a width direction and a thickness. The surface along the direction is called the WT surface. Therefore, in the solid electrolytic capacitor 1 shown in FIG. 1, the first end surface 9a and the second end surface 9b of the resin molded body 9 are WT surfaces, the bottom surface 9c and the top surface 9d are LW surfaces, and the first side surface 9e and the first side surface 9e and the first surface 9d. The 2 side surface 9f is an LT surface.

FIG. 2 is a cross-sectional view taken along the line II-II of the solid electrolytic capacitor shown in FIG.
The resin molded body 9 includes a laminated body 30 in which a plurality of capacitor elements 20 are laminated, and a sealing resin 8 that seals the periphery of the laminated body 30. In the example shown in FIG. 2, eight capacitor elements 20A, 20B, 20C, 20D, 20E, 20F, 20G, and 20H are laminated. The stacking direction of the capacitor elements 20 is parallel to the thickness direction (T direction) of the resin molded body 9.

In the example shown in FIG. 2, the support substrate 9 g is provided on the bottom of the resin molded body 9, and the bottom surface of the support substrate 9 g is the bottom surface 9c of the resin molded body 9. The support substrate 9g is provided to integrate the laminated body 30 of the capacitor elements 20.

The capacitor element 20 includes an anode 3 having a dielectric layer 5 on its surface, and a cathode 7 facing the anode 3 via the dielectric layer 5. In the laminated body 30, the laminated capacitor elements 20 may be bonded to each other via a conductive adhesive (not shown). In that case, the conductive adhesive is also regarded as a part of the cathode 7.

The anode 3 constituting the capacitor element 20 includes a valve acting metal substrate 3a. The valve acting metal substrate 3a has a porous portion such as an etching layer on the surface of the core portion. A dielectric layer 5 is provided on the surface of the porous portion.

The valve acting metal substrate 3a is drawn out to the first end surface 9a of the resin molded body 9. The first external electrode 11 provided on the first end surface 9a of the resin molded body 9 is electrically connected to the valve acting metal substrate 3a exposed from the first end surface 9a.

The cathode 7 constituting the capacitor element 20 includes a solid electrolyte layer 7a formed on the dielectric layer 5, a conductive layer 7b formed on the solid electrolyte layer 7a, and a cathode extraction layer formed on the conductive layer 7b. Includes 7c and.

The cathode drawing layer 7c is drawn out to the second end surface 9b of the resin molded body 9. The second external electrode 13 provided on the second end surface 9b of the resin molded body 9 is electrically connected to the cathode extraction layer 7c exposed from the second end surface 9b.

Between the set of capacitor elements 20D and 20E adjacent to each other in the stacking direction of the capacitor elements 20, that is, the thickness direction (T direction) of the resin molded body 9, the cathode 7 of one capacitor element 20D and the other capacitor element 20E There is a non-contact region 41 in which the cathode 7 of the capacitor element 7 does not contact, and a contact region 42 surrounding the non-contact region 41 in which the cathode 7 of one capacitor element 20D and the cathode 7 of the other capacitor element 20E are in contact with each other. In the contact region 42, the cathodes 7 are in mechanical and electrical contact with each other, and in the non-contact region 41, the cathodes 7 are not in mechanical or electrical contact with each other.

In the example shown in FIG. 2, the cathode extraction layer 7c forming a part of the cathode 7 is located in the capacitor element 20D, and a non-contact region 41 is formed between the cathode element 20E and the cathode 7 on the opposite side. The cathode extraction layer 7c forming a part of the cathode 7 may be located on the capacitor element 20E, and a non-contact region 41 may be formed between the cathode element 20D and the cathode 7 on the opposite side.

On the other hand, in the vicinity of the first end surface 9a and the second end surface 9b of the resin molded body 9, the contact region 42 is formed by the cathode 7 of the capacitor element 20D and the cathode 7 of the capacitor element 20E coming into contact with each other.

By providing the non-contact region of the cathode between the capacitor elements, it is possible to relieve the thermal stress due to heating at the time of manufacturing or reflowing the solid electrolytic capacitor. As a result, the laminated capacitor elements are less likely to be peeled off, so that the change in ESR due to thermal stress can be reduced.

Furthermore, by providing the contact region of the cathode so as to surround the non-contact region, the laminated capacitor elements are less likely to peel off regardless of the direction in which the thermal stress is applied, so that the thermal stress can be relaxed. it can.

FIG. 3 is a plan view of the resin molded product shown in FIG. 2 as viewed from the thickness direction.
As shown in FIG. 3, the non-contact region 41 surrounded by the contact region 42 is preferably located at the center of the resin molded body 9 in the length direction (L direction) and the width direction (W direction). .. In this case, the thermal stress applied from the bottom surface side and the top surface side of the solid electrolytic capacitor can be effectively relieved.

The size of the non-contact region 41 should be 1/3 or more and 2/3 or less of the dimensions in the length direction (L direction) and the width direction (W direction) of the resin molded body 9 for relaxation of thermal stress and resin molding. It is preferable to achieve both body adhesion and body adhesion. When the adjacent capacitor elements 20 are joined to each other via a conductive adhesive, the conductive adhesive may be provided in the same planar shape as the shape of the contact region 42.

In the present specification, the central portion in the length direction and the width direction of the resin molded body means a region including the center in the length direction and the width direction of the resin molded body. Preferably, in the length direction of the resin molded body, it is inside a distance of 1/2 or less of the distance from the center of the resin molded body to the first end face or the second end face, and in the width direction of the resin molded body. It means a region inside a distance of 1/2 or less of the distance from the center of the resin molded body to the first side surface or the second side surface.

As shown in FIG. 2, the non-contact region 41 is located between a set of capacitor elements (capacitor elements 20D and 20E in FIG. 2) closest to the central portion in the thickness direction (T direction) of the resin molded body 9. It is preferable to do so. In this case, the thermal stress applied from the bottom surface side and the top surface side of the solid electrolytic capacitor can be effectively relieved.

The arrangement, number, shape, etc. of the non-contact region 41 are not limited to the examples shown in FIGS. 2 and 3. For example, examples of the planar shape of the non-contact region 41 seen from the thickness direction (T direction) of the resin molded body 9 include an ellipse, a circle, and a rectangle. The planar shape of the non-contact region 41 may be a symmetrical shape or an asymmetrical shape.

The non-contact region 41 may exist between any one set of capacitor elements adjacent to each other in the stacking direction, or may exist between two or more sets of capacitor elements adjacent to each other in the stacking direction. For example, the non-contact region 41 may exist not only between the capacitor elements 20D and 20E but also between the capacitor elements 20A and 20B and between the capacitor elements 20B and 20C. Further, the non-contact region 41 may not exist between the capacitor elements 20D and 20E.

In the example shown in FIG. 3, one non-contact region 41 exists between a set of capacitor elements, but a plurality of non-contact regions 41 may exist between a set of capacitor elements.

The non-contact region 41 is preferably a void. Alternatively, at least a part of the non-contact region 41 may be filled with an insulating material. Since damage to each capacitor element itself due to thermal stress can be easily reduced, it is more preferable that the non-contact region 41 is a void.

FIG. 4 is a cross-sectional view schematically showing another example of the solid electrolytic capacitor of the present invention.
In the solid electrolytic capacitor 1A shown in FIG. 4, a part of the non-contact region 41 is filled with the insulating material 43.

Examples of the insulating material 43 include an insulating resin and the like. Examples of the insulating resin include epoxy resin, silicone resin, phenol resin and the like. The insulating material 43 preferably has adhesiveness.

From the viewpoint of stress relaxation, the insulating resin constituting the insulating material 43 is preferably a resin having a smaller coefficient of linear expansion than the sealing resin 8 constituting the resin molded body 9.

Although the entire non-contact region 41 may be filled with the insulating material 43, it is preferable that the insulating material 43 is filled so that a gap remains in a part of the non-contact region 41.

The valve-acting metal substrate 3a is made of a valve-acting metal exhibiting a so-called valve action. Examples of the valve acting metal include simple metals such as aluminum, tantalum, niobium, titanium, zirconium, magnesium and silicon, or alloys containing these metals. Among these, aluminum or an aluminum alloy is preferable.

The shape of the valve acting metal substrate 3a is not particularly limited, but it is preferably flat, more preferably foil.

Since the specific surface area of the valve acting metal substrate 3a is increased due to the porous portion provided on the surface of the valve acting metal substrate 3a, the capacitance of the solid electrolytic capacitor 1 can be increased. Examples of the porous portion include an etching layer formed on the surface of the valve acting metal substrate 3a, a porous layer formed by printing and sintering on the surface of the valve acting metal substrate 3a, and the like. When the valve acting metal is aluminum or an aluminum alloy, it is preferably an etching layer, and when it is titanium or a titanium alloy, it is preferably a porous layer.

The thickness of the valve acting metal substrate 3a is not particularly limited, but the thickness of the core portion excluding the porous portion is preferably 5 μm or more and 100 μm or less. The thickness of the porous portion (thickness on one side) is preferably 5 μm or more and 200 μm or less.

The thickness of the valve acting metal substrate 3a described above is the thickness inside the valve acting metal substrate 3a excluding the portion exposed from the end face.

The dielectric layer 5 is preferably made of an oxide film of the valve acting metal. For example, when an aluminum foil is used as the valve acting metal substrate 3a, the dielectric layer 5 is formed by anodizing in an aqueous solution containing boric acid, phosphoric acid, adipic acid, or a sodium salt or ammonium salt thereof. It is possible to form an oxide film.

The dielectric layer 5 is formed along the surface of the porous portion, so that pores (recesses) are formed. The thickness of the dielectric layer 5 is designed according to the withstand voltage and capacitance required for the solid electrolytic capacitor, but is preferably 10 nm or more, and preferably 100 nm or less.

Further, from the viewpoint of increasing the production efficiency of the solid electrolytic capacitor, a chemical conversion foil which has been subjected to a chemical conversion treatment in advance may be used as the valve acting metal substrate 3a on which the dielectric layer 5 is formed on the surface.

Examples of the material constituting the solid electrolyte layer 7a include conductive polymers having pyrroles, thiophenes, anilines and the like as skeletons. Examples of the conductive polymer having thiophenes as a skeleton include PEDOT [poly (3,4-ethylenedioxythiophene)], and PEDOT: PSS complexed with polystyrene sulfonic acid (PSS) as a dopant. It may be.

For the solid electrolyte layer 7a, for example, a polymer film such as poly (3,4-ethylenedioxythiophene) is formed on the surface of the dielectric layer 5 using a treatment liquid containing a monomer such as 3,4-ethylenedioxythiophene. It is formed by a method of forming, a method of applying a dispersion liquid of a polymer such as poly (3,4-ethylenedioxythiophene) to the surface of the dielectric layer 5, and drying. After forming the solid electrolyte layer for the inner layer that fills the pores (recesses), it is preferable to form the solid electrolyte layer for the outer layer that covers the entire dielectric layer.

The solid electrolyte layer 7a can be formed in a predetermined region by applying the above-mentioned treatment liquid or dispersion liquid onto the dielectric layer 5 by sponge transfer, screen printing, spray coating, dispenser, inkjet printing, or the like. .. The thickness of the solid electrolyte layer 7a is preferably 2 μm or more, and preferably 20 μm or less.

The conductive layer 7b is provided to electrically and mechanically connect the solid electrolyte layer 7a and the cathode extraction layer 7c. The conductive layer 7b is preferably a carbon layer, graphene layer or silver layer formed by applying a conductive paste such as carbon paste, graphene paste or silver paste. Further, the conductive layer 7b may be a composite layer in which a silver layer is provided on the carbon layer or the graphene layer, or a mixed layer in which the carbon paste or the graphene paste and the silver paste are mixed.

The conductive layer 7b can be formed by applying a conductive paste such as carbon paste on the solid electrolyte layer 7a by sponge transfer, screen printing, spray coating, dispenser, inkjet printing or the like. It is preferable that the cathode drawing layer 7c in the next step is laminated in a viscous state before the conductive layer 7b is dried. The thickness of the conductive layer 7b is preferably 2 μm or more, and preferably 20 μm or less.

A conductive adhesive layer may be provided on the conductive layer 7b. Examples of the material constituting the conductive adhesive layer include a mixture of an insulating resin such as an epoxy resin and a phenol resin and conductive particles such as carbon and silver.

The cathode lead-out layer 7c can be formed of a metal foil or a printed electrode layer.

When the cathode lead-out layer 7c is made of a metal foil, the metal foil is at least one selected from the group consisting of aluminum, nickel, copper, silver, alloys containing these metals as main components, and stainless steel (SUS). It is preferably made of metal. When the metal foil is made of the above metal, the resistance value of the metal foil can be reduced and the ESR can be reduced. Further, as the metal foil, a metal foil having a surface coated with carbon or titanium by a film forming method such as sputtering or vapor deposition may be used. It is more preferable to use carbon coated aluminum foil.

The thickness of the metal foil is not particularly limited, but from the viewpoint of handling in the manufacturing process, miniaturization, and reduction of ESR, it is preferably 20 μm or more, and preferably 50 μm or less.

It is preferable that a roughened surface is formed on the surface of the metal foil. When the roughened surface is formed on the surface of the metal foil, the adhesion between the cathode lead-out layer 7c and the conductive layer 7b and the like is improved, so that the ESR can be reduced. The method for forming the roughened surface is not particularly limited, and the roughened surface may be formed by etching or the like. In particular, when an aluminum foil is used, it is preferable to apply carbon coating or titanium coating to the surface that has been roughened by etching or the like in order to reduce the resistance.

Further, a coat layer made of an anchor coating agent may be formed on the surface of the metal foil. When a coating layer made of an anchor coating agent is formed on the surface of the metal foil, the adhesion between the cathode drawing layer 7c and the conductive layer 7b and the like is improved, so that ESR can be reduced.

When the cathode extraction layer 7c is composed of a printed electrode layer, the cathode extraction layer 7c is formed in a predetermined region by applying the electrode paste on the conductive layer 7b by sponge transfer, screen printing, spray coating, dispenser, inkjet printing, or the like. can do. As the electrode paste, an electrode paste containing nickel, silver or copper as a main component is preferable. When the cathode lead-out layer 7c is used as the print electrode layer, the cathode lead-out layer 7c can be made thinner than when the metal foil is used. For example, in the case of screen printing, the thickness can be 2 μm or more and 20 μm or less.

The thickness of the cathode extraction layer 7c described above is the thickness inside the cathode extraction layer 7c excluding the portion exposed from the end face.

The sealing resin 8 constituting the resin molded product 9 contains at least a resin, preferably a resin and a filler. Examples of the resin contained in the sealing resin 8 include epoxy resin, phenol resin, polyimide resin, silicone resin, polyamide resin, liquid crystal polymer and the like. As the form of the resin, either a solid resin or a liquid resin can be used. Examples of the filler contained in the sealing resin 8 include silica particles, alumina particles, and metal particles. It is more preferable to use a material containing silica particles in the solid epoxy resin and the phenol resin as the sealing resin 8.

When the sealing resin 8 contains the resin and the filler, the maximum diameter of the filler is preferably smaller than the minimum thickness of the cathode lead-out layer 7c from the viewpoint of ensuring the filling property of the sealing resin 8. The maximum diameter of the filler is preferably in the range of, for example, 30 μm or more and 40 μm or less.

As a molding method of the resin molded body 9, when a solid sealing material is used, it is preferable to use a resin mold such as a compression mold or a transfer mold, and it is more preferable to use a compression mold. When a liquid encapsulant is used, it is preferable to use a molding method such as a dispensing method or a printing method. It is preferable that the laminate 30 of the capacitor elements 20 is sealed with the sealing resin 8 by the compression mold to obtain the resin molded body 9.

As shown in the example shown in FIG. 2, it is preferable that the support substrate 9g is provided on the bottom of the resin molded body 9. The support substrate 9 g is preferably made of an insulating material. Examples of the insulating material constituting 9 g of the support substrate include glass epoxy resin, glass composite, phenol resin, polyimide resin, polyamide resin, fluororesin, polyphenylene oxide (PPO) resin, bismaleimide triazine (BT) resin and the like. ..

It is preferable that the corners of the resin molded body 9 are rounded by barrel polishing after the resin molding. The corner portion is a portion where the three surfaces of the resin molded body 9 intersect. Since the resin molded body is softer than the ceramic body, it is difficult to form rounded corners by barrel polishing, but the radius of curvature can be reduced by adjusting the composition, particle size, shape, barrel processing time, etc. of the media. Can form a roundness.

The first external electrode 11 and the second external electrode 13 can be formed by, for example, plating, sputtering, dip coating, printing, or the like. As the plating layer, Zn / Ag / Ni layer, Ag / Ni layer, Ni layer, Zn / Ni / Au layer, Ni / Au layer, Zn / Ni / Cu layer, Ni / Cu layer and the like can be used. .. It is preferable to further form, for example, a Cu plating layer, a Ni plating layer, and a Sn plating layer in this order (or except for a part) on these plating layers.

[Manufacturing method of solid electrolytic capacitor]
The solid electrolytic capacitor of the present invention can be manufactured, for example, by the following method.

(Manufacturing of capacitor element)
First, a valve acting metal substrate such as an aluminum foil having a porous portion such as an etching layer on the surface of the core portion is prepared, and the surface of the porous portion is anodized to form a dielectric layer. Next, a solid electrolyte layer is formed on the dielectric layer by screen printing, subsequently, a carbon layer to be a conductive layer is formed on the solid electrolyte layer by screen printing, and an electrode lead-out layer is laminated on the carbon layer. Alternatively, it is formed by screen printing. A capacitor element is obtained by the above steps.

(Preparation of resin molded product)
After laminating a plurality of capacitor elements, they are crimped by a thermocompression bonding press or the like to prepare a laminated body. It is preferable that the capacitor elements are laminated on the support substrate. After that, the laminate is sealed with a sealing resin by a compression mold or the like. A resin molded product is obtained by the above steps.

For example, among the capacitor elements adjacent to each other in the stacking direction, the thickness and coating area of at least one of the cathodes (for example, the thickness of the carbon layer and the coating area) can be changed, and the pressure during crimping or sealing can be defined as the non-contact region. It is possible to form a non-contact region of the cathode by weakening the region in the vicinity of the region. Alternatively, it is also possible to apply a paraffin-based wax to a region to be a non-contact region and heat the region to scatter the wax to form a non-contact region of the cathode.

Further, by sandwiching an insulating film or the like between the capacitor elements in advance, it is possible to fill at least a part of the non-contact region with the insulating material.

A resin molded product may be produced by the production method described in JP-A-2019-79866. The method for producing the resin molded product includes a step of preparing a first sheet, a step of preparing a second sheet, a step of coating the first sheet with an insulating material, and a step of conducting conductivity on the solid electrolyte layer of the first sheet. A step of forming a body layer, a step of laminating a first sheet and a second sheet to prepare a laminated sheet, a step of sealing with a sealing resin to prepare a laminated block body, and cutting the laminated block body. Thereby, it has a step of producing a plurality of resin molded bodies.

The first sheet is a sheet provided with a valve acting metal substrate having a dielectric layer formed on its surface and a solid electrolyte layer provided on the dielectric layer, and the second sheet is a sheet made of a metal foil. Is. The first sheet and the second sheet each have a through hole in a portion to be a first end face or a second end face of the resin molded body, so that the through hole communicates with each other when forming a laminated sheet. .. Then, when sealing with the sealing resin, the through holes are filled with the sealing resin to prepare a laminated block body. A resin molded body can be obtained by cutting this laminated block body so as to separate the sealing resin sealed in the through hole. In this resin molded body, the valve acting metal substrate is divided into a plurality of anode portions and exposed by the sealing resin sealed in the through holes. Further, the cathode lead-out layer is also divided into a plurality of cathode portions and exposed by the sealing resin sealed in the through holes.

(Formation of external electrodes)
The first external electrode is formed on the first end surface of the resin molded body, and the second external electrode is formed on the second end surface of the resin molded body. By the above steps, the solid electrolytic capacitor of the present invention can be obtained.

The solid-state electrolytic capacitor of the present invention is not limited to the above-described embodiment, and various applications and modifications can be applied within the scope of the present invention regarding the configuration, manufacturing conditions, and the like of the solid-state electrolytic capacitor.

1, 1A Solid Electrode Capacitor 3 Anode 3a Valve Acting Metal Base 5 Dielectric Layer 7 Cathode 7a Solid Electrode Layer 7b Conductive Layer 7c Cathode Drawer Layer 8 Encapsulating Resin 9 Resin Molded Body 9a First End Face 9b Second End Face 9c Bottom 9d Top 9e 1st side surface 9f 2nd side surface 9g Support substrate 11 1st external electrode 13 2nd external electrode 20, 20A, 20B, 20C, 20D, 20E, 20F, 20G, 20H Capacitor element 30 Laminated body 41 Non-contact area 42 Contact area 43 Insulation material

Claims (5)

The laminate includes a laminate in which a plurality of capacitor elements are laminated, and a sealing resin that seals the periphery of the laminate, and the bottom surface and the top surface facing the thickness direction parallel to the lamination direction of the capacitor elements, and the laminate. A resin molded body having a first end surface and a second end surface facing in a length direction orthogonal to the direction, and a first side surface and a second side surface facing the width direction orthogonal to the stacking direction and the length direction.
A first external electrode provided on the first end surface of the resin molded body and
A second external electrode provided on the second end surface of the resin molded body and
A solid electrolytic capacitor with
The capacitor element includes an anode having a dielectric layer on its surface and a cathode facing the anode via the dielectric layer.
The anode contains a valvular metal substrate having a porous portion on the surface of the core portion.
The cathode includes a cathode lead-out layer.
The first external electrode is electrically connected to the valve acting metal substrate exposed from the first end face, and is electrically connected to the valve acting metal substrate.
The second external electrode is electrically connected to the cathode lead-out layer exposed from the second end face.
Between at least one set of capacitor elements adjacent to each other in the stacking direction, a non-contact region in which the cathode of one capacitor element and the cathode of the other capacitor element do not contact and the non-contact region are surrounded by one capacitor element. A solid electrolytic capacitor in which there is a contact area where the cathode of the capacitor and the cathode of the other capacitor element are in contact with each other. The solid electrolytic capacitor according to claim 1, wherein the non-contact region is located at a central portion in the length direction and the width direction of the resin molded product. The solid electrolytic capacitor according to claim 1 or 2, wherein the non-contact region is located between a set of capacitor elements closest to the central portion in the thickness direction of the resin molded product. The solid electrolytic capacitor according to any one of claims 1 to 3, wherein the non-contact region is a void. The solid electrolytic capacitor according to any one of claims 1 to 3, wherein at least a part of the non-contact region is filled with an insulating material.

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