JP3958725B2 - Surface mount thin capacitor and manufacturing method thereof - Google Patents

Description

  The present invention relates to a solid electrolytic capacitor using a polymer as an electrolyte, and more particularly to a surface mount thin capacitor and a method for manufacturing the same.

  Conventionally, as this type of capacitor, those shown in FIG. 4 and FIG. 5 are known (hereinafter referred to as the prior arts 1 and 2, respectively).

  The solid electrolytic capacitor according to the prior art 1 shown in FIG. 4 is called a three-terminal transmission line element type (for example, see Patent Document 1). In this solid electrolytic capacitor according to the prior art 1, the conductive functional polymer film 12 is a solid electrolyte, and an anodic oxide film layer is formed on the surface of the valve action metal to form an anode body 10 of the valve action metal. The conductive functional polymer film 12 is formed so as to cover the center part of the surface of the anodic oxide coating layer 10, the graphite layer 13 is formed around the conductive polymer film 12, and the silver paste layer is sequentially formed as the cathode layer 14. After that, the anode terminal 11 is joined to both ends of the anode body 10 extending further outward through the portion where the resist 16 is formed. The upper periphery of the cathode layer 14 (silver paste layer) is covered with a heat-adhesive resin-impregnated tape 15a, and the upper side thereof is covered with an element reinforcing metal plate 17, and the lower side of the cathode layer 14 (silver paste layer) is covered. Around the periphery, a hole 15c is provided in a heat-adhesive resin-impregnated tape 15b, and after filling with a conductive paste 19, a cathode terminal 18 is formed to form a surface-mounted capacitor.

In the solid electrolytic capacitor according to Prior Art 2, the anode body 20 and the anode terminal 21 are connected only by ultrasonic welding (welding) as shown in FIG.
JP 2002-313676 A

  However, the anode terminal 21 is connected only by ultrasonic welding (welding) to the anode body 20, and the connection strength is weak because the anode terminal 21 and the thermoadhesive insulating resin impregnated tape 25 are not connected. If the heat-adhesive green resin-impregnated tape 25 is longer than the anode body 20, the resin is likely to adhere to the terminal mounting surface side (opposite to the anode body connection surface) during high-temperature pressure curing. It causes a defect.

  The technical problem of the present invention is to provide a surface mount thin capacitor of a high capacity and low ESR product that can improve the anode terminal connection strength and can be easily laminated.

  According to the present invention, in a solid electrolytic capacitor having a plate-like or foil-like surface-enhanced metal having an anode body and a conductive polymer layer / graphite layer / silver layer as a cathode layer, A pair of anode terminals that are bent into a U-shaped cross-section so as to cover both sides, and connected to the anode body, and impregnated with a heat-adhesive insulating resin attached on the anode terminal and the anode body A tape and a metal plate are provided, and the anode terminal and the heat-adhesive insulating resin-impregnated tape are connected by curing the heat-adhesive insulating resin-impregnated tape and the metal plate at high temperature and pressure. A surface mount thin capacitor is obtained.

  Further, according to the present invention, the first and second anode bodies made of an enlarged metal having a plate-like or foil-like valve action, and the cathode layer made of conductive polymer layer / graphite layer / silver layer In the solid electrolytic capacitor having the first and second anodes, the first and second anodes are bent into a U-shaped cross section so as to cover both sides of the anode body in order to connect to the first and second anode bodies, respectively. A terminal pair, a heat-adhesive insulating resin-impregnated tape affixed to the first and second anode terminal pairs and the anode body, and an element reinforcing metal plate covering an upper side of the heat-adhesive insulating resin-impregnated tape And connecting the anode terminal and the thermally adhesive insulating resin impregnated tape by high-temperature pressurizing and curing the thermally adhesive insulating resin impregnated tape and the metal plate, the first and second The bent parts of the anode terminals of However, the first layer including the first anode terminal and the first anode terminal pair, and the second layer including the second anode terminal and the second anode terminal pair are connected using a conductive paste or a plating method. A surface-mount thin capacitor characterized in that two layers are laminated is obtained.

  Further, according to the present invention, the concave portion formed in a state where the anode terminal is bent in a U-shape is bent so as to be larger than the thickness of the anode body and to cover the anode body. A gap is formed between one of the convex portions of the bent anode terminal and the anode body, and the thermoadhesive green resin-impregnated tape layer is formed in the gap. A surface mount thin capacitor is obtained.

According to the present invention, there is also provided a method for producing a solid electrolytic capacitor having a plate-like or foil-like surface-enhanced metal having an anode body and a conductive polymer layer / graphite layer / silver layer as a cathode layer. In order to connect the anode terminal to the anode body, the thickness of the recess formed in a state where the anode terminal is folded in a U-shaped cross section is larger than the thickness of the anode body, and the anode A step of bending so as to cover the body, a step of attaching a heat-adhesive insulating resin-impregnated tape and a metal plate thereon, and an anode terminal and a heat-adhesive insulating resin-impregnated tape by curing at high temperature and pressure. A step of connecting, and a step of forming the thermoadhesive green resin-impregnated tape layer in a gap between one of the convex portions of the bent anode terminal and the anode body , Of surface mount thin capacitors Production method can be obtained.

  According to the surface mount thin capacitor according to the present invention, ultrasonic welding (welding) is performed when connecting the anode terminal in a solid electrolytic capacitor having a plate-like or foil-like surface-enhanced metal having a valve action as an anode body. In this way, electrical connection is performed, and bending is performed so that the side surface of the terminal covers the anode body, and a heat-adhesive insulating resin-impregnated tape is applied thereon, so that the connection strength of the anode terminal can be maintained. .

  Further, according to the surface mount thin capacitor according to the present invention, a plurality of the anode terminal bending portions can be laminated by connecting the anode terminals with each other using solder, conductive paste, plating method, etc. High-capacity and low-ESR surface-mount thin capacitors can be provided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a cross-sectional view of a solid electrolytic capacitor according to an embodiment of the present invention. A surface-mount thin capacitor according to an embodiment of the present invention will be described with reference to FIG. First, an anodic oxide film layer is formed on the surface of the valve metal, thereby forming the anode 1 of the valve metal. After forming a silver paste layer as the cathode layer 4 around the center of the anode body 1, anode terminals 11 are connected so as to cover both ends of the anode body 1 extending outward. The cathode layer 4 is composed of a conductive polymer layer, a graphite layer, and a silver layer, and the upper side surface integration and lower side surface integration of the anode body 1 are strengthened by bending the anode terminal 3 and ultrasonic welding (welding). Connected.

  Here, the connection method of the anode terminal 3 and the anode body 1 can also be other connection methods. For example, as shown in FIG. 2, the thickness of the concave portion (thickness in the height direction in FIG. 2) formed in a state where the anode terminal 3 is bent in a U-shape is larger than the thickness of the anode body 1. It is bent. The concave portion is bent in a direction covering the anode body 1, and a heat-adhesive insulating resin-impregnated tape 5 is further applied thereon so as to cover the cathode layer 4, and then a metal plate 7 for element reinforcement is further attached. Apply and cure at high temperature and pressure. As a result, the heat-adhesive insulating resin-impregnated tape 5 adheres to not only the anode body 1 and the cathode layer 4 but also the anode terminal 3, thereby preventing peeling of the interface between the anode body 1 and the anode terminal 3.

  Here, the description returns to FIG. When connecting the anode terminal 3, the anode body 1 and the anode terminal 3 are electrically connected by ultrasonic welding (welding), and bending is performed so that the side surface of the anode terminal 3 covers the anode body 1. A thermal adhesive insulating resin impregnated tape 5 is attached from above. The bending of the anode terminal 3 described above is performed in a U-shaped cross section as can be seen with reference to FIG. Furthermore, it can be easily understood that the connection strength between the anode terminal 3 and the anode body 1 is improved because the heat-adhesive insulating resin-impregnated tape 5 is stuck thereon.

  Further, the upper periphery of the cathode layer 4 (silver paste layer) is covered with a heat-adhesive insulating resin-impregnated tape 5, and the upper side thereof is covered with an element reinforcing metal plate 7. After the conductive paste 9 is filled around the lower side of the cathode layer 4 (silver paste layer), the cathode terminal 8 is formed to obtain a single-layer surface-mount thin capacitor.

  FIG. 3 is a cross-sectional view of a solid electrolytic capacitor according to another embodiment of the present invention. A surface mount thin capacitor according to another embodiment of the present invention will be described with reference to FIG. The other embodiment of the present invention is basically the same as the above-described one embodiment except that two anode terminal bending portions are provided, and thus the description thereof is omitted. Hereinafter, different points will be described. First, two anode terminal bending portions are provided, and a plurality of anode terminals 3a and 3b are connected to each other and stacked using solder, conductive paste, plating method, or the like. Further, in the cathode layer (silver paste layer) 4, a plurality of layers are laminated by connecting the cathode layers 4 with the conductive paste 9 or the like to obtain a multilayer surface mount thin capacitor.

  The surface-mount thin capacitor according to the present invention can be applied to a type of electric capacitor that is surface-mounted on a substrate such as a printed wiring board of an electronic component or an electric component.

(A) is the anode-cathode side sectional drawing of the solid electrolytic capacitor by one embodiment of this invention, (b) is the sectional view on the AA line of (a). It is an anode-cathode side sectional view for explaining other embodiments of bending processing of an anode terminal. It is the anode-cathode side sectional drawing of the solid electrolytic capacitor by further another embodiment of this invention, (b) is the sectional view on the AA line of (a). It is sectional drawing which shows the solid electrolytic capacitor by the prior art 1. FIG. (A) is the anode-cathode side sectional drawing which shows the solid electrolytic capacitor by the prior art 2, (b) is the sectional view on the AA line of (a).

Explanation of symbols

1, 1a, 1b, 10, 20 Anode body 3, 3a, 3b, 11, 21 Anode terminal 4, 14 Cathode layer 5, 5a, 5b, 15a, 15b, 25 Thermal adhesive insulating resin impregnated tape 7, 17 Element reinforcement Metal plate 8, 18 Cathode terminal 9, 19 Conductive paste 12 Conductive functional polymer film 12d, 13d, 14d Both ends 13 Graphite layer 16 Resist

Claims (4)

In a solid electrolytic capacitor having a plate-like or foil-like surface-enhanced metal having an anode body as an anode body and a conductive polymer layer / graphite layer / silver layer as a cathode layer,
A pair of anode terminals that are bent into a U-shaped cross section so as to cover both sides of the anode body, and connected to the anode body;
A heat-adhesive insulating resin-impregnated tape and a metal plate attached on the anode terminal and the anode body,
A surface-mounting thin capacitor characterized in that the anode terminal and the thermally adhesive insulating resin impregnated tape are connected by curing the thermally adhesive insulating resin impregnated tape and the metal plate at a high temperature and pressure. In a solid electrolytic capacitor comprising first and second anode bodies made of a metal having a plate-like or foil-like valve action and a cathode layer made of a conductive polymer layer / graphite layer / silver layer,
First and second anode terminal pairs bent into a U-shaped cross section so as to cover both sides of the anode body in order to connect to the first and second anode bodies, respectively;
A heat-adhesive insulating resin-impregnated tape affixed to the first and second anode terminal pairs and the anode body;
An element reinforcing metal plate covering the upper side of the thermally adhesive insulating resin impregnated tape;
By connecting the anode terminal and the thermal adhesive insulating resin impregnated tape by high-temperature pressurizing and curing the thermal adhesive insulating resin impregnated tape and the metal plate,
The bent portions of the first and second anode terminals are connected to each other using a solder, a conductive paste, or a plating method, and include a first anode terminal and a first anode terminal pair. And a second layer including the second anode terminal and the second anode terminal pair.   Bending is performed so that the thickness of the concave portion formed in a state where the anode terminal is bent in a U-shaped cross section is larger than the thickness of the anode body, and the anode body is covered. 3. The surface according to claim 1, wherein a gap is formed between one of the convex portions of the anode terminal and the anode body, and the thermoadhesive green resin impregnated tape layer is formed in the gap. Mounting thin capacitor. In a method for producing a solid electrolytic capacitor having a plate-like or foil-like surface-enhanced metal having an anode body and a conductive polymer layer / graphite layer / silver layer as a cathode layer,
In order to connect the anode terminal to the anode body, the thickness of the concave portion formed in a state where the anode terminal is folded in a U-shape is larger than the thickness of the anode body, and the anode body is A process of bending to cover,
A step of attaching a heat-adhesive insulating resin impregnated tape and a metal plate thereon,
A step of connecting the anode terminal and the thermally adhesive insulating resin-impregnated tape by high-temperature pressure curing;
A surface mount thin capacitor comprising a step of forming the thermoadhesive green resin impregnated tape layer in a gap between one of both convex portions of the bent anode terminal and the anode body Production method.

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