JP2002270468A - Capacitor manufacturing method and capacitor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a capacitor manufacturing method, which can eliminate a creep phenomenon considered to be caused directly by an electric short circuit and makes a capacitor small-sized and large in capacitance even when the sizes of an anode body and an anode terminal become shorter in the manufacturing process of the capacitor, and to provide the capacitor. SOLUTION: Before or after a dielectric film is formed on the anode body of the capacitor (solid electrolytic capacitor), a resin costing is formed by applying and drying a fluororesin water repellent to which silicone resin is added at a specific mixing rate near the anode lead.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for downsizing electronic components, and more particularly, to an electrical short circuit even when the size of an anode body and an anode terminal becomes shorter and shorter during a capacitor manufacturing process. Crawling of the semiconductor base material, which is considered to be the direct cause of
As a result, the present invention relates to a capacitor manufacturing method and a capacitor capable of reducing the size and capacity of the capacitor.

[0002]

2. Description of the Related Art In recent years, electronic components have tended to be miniaturized.
In particular, in a solid electrolytic capacitor using a valve metal, the dimensions of the anode body and the anode terminal are becoming shorter and shorter with the progress of miniaturization and large capacity. For this reason, even during the manufacturing process of the solid electrolytic capacitor, the occurrence of the phenomenon that the electrolyte layer creeps up on the anode lead often directly causes an electrical short circuit.

For this reason, conventionally, a resin coating film is formed on a part of the anode lead using a fluorine-based material or a silicone-based material to prevent the electrolyte layer from creeping up (hereinafter referred to as a creeping-up prevention method). ).

[0004] Such a prior art is disclosed, for example, in JP-A-56-083023 (first prior art). The prior art described in Japanese Patent Application Laid-Open No. 56-083023 discloses a capacitor in which one of a water-repellent agent such as silicone resin and fluorine resin is applied to the vicinity of the root of a lead before forming a dielectric film. I have.

The prior art (second prior art) described in Japanese Patent Application Laid-Open No. 2000-216061 and Japanese Patent Application Laid-Open No.
The prior art described in Japanese Patent No. 7519 (third prior art) and the prior art described in Japanese Patent No. 3080851 (fourth prior art) include a silicone resin as a water repellent near the root of a lead after forming a dielectric film. There is disclosed a capacitor coated with any one of fluorinated resin and the like.

The prior art (fifth prior art) described in JP-A-10-316820 and JP-A-5-177
No. 768, the prior art (sixth prior art) includes:
Although the purpose is different than the one used for the capacitor,
A member having a super-water-repellent surface formed by a surface layer containing silicone and a water-repellent fluororesin is disclosed.

[0007]

However, in the above-mentioned first to fourth prior arts, the water-repellent and oil-repellent properties and the chemical resistance of the fluorine-based material are determined by immersion or heating in the chemical performed during the formation of the electrolyte layer. However, there is a problem that the electrolyte layer is formed on the resin coating film or over the resin coating film. Also, when a silicone-based material is used, although water- and oil-repellency and chemical resistance, which were insufficient with a fluorine-based material, are improved, the resin coating is thicker than the fluorine-based material, and the non-adhesiveness is inferior. In the worst case, it is difficult to obtain a stable and highly accurate coating state, and in the worst case, the resin coating that penetrates the anode body inhibits the formation of the dielectric coating and the electrolyte layer and adversely affects the electrical characteristics of the capacitor There was a point.

In the fifth and sixth prior arts, a member having a super water-repellent surface formed by a surface layer containing silicone and a water-repellent fluororesin is disclosed. However, there is no suggestion to which part of the capacitor such a member should be applied.

The present invention has been made in view of such a problem, and an object thereof is to provide a case where the dimensions of an anode body and an anode terminal become shorter and shorter during a capacitor manufacturing process. This also eliminates the phenomenon of creeping up of the semiconductor base material, which is considered to be the direct cause of the electrical short circuit, resulting in the miniaturization of capacitors (particularly solid electrolytic capacitors using valve metal). It is another object of the present invention to provide a capacitor manufacturing method and a capacitor which can be realized.

[0010]

The gist of the present invention is to provide a fluorine resin-based water repellent in which a silicone resin is added to a part of an anode lead at a predetermined mixing ratio. A method for manufacturing a capacitor, comprising a step of applying the fluororesin-based water-repellent agent to a part of the anode lead and drying to form a resin coating film. Further, the gist of the invention according to claim 2 of the present invention is that, before the formation of the dielectric film on the anode body, the fluorine resin-based material is provided near the anode body side of the anode lead connecting the anode body and the anode terminal. The method for producing a capacitor according to claim 1, further comprising a step of forming a dried resin film by applying a water repellent agent. The gist of the invention described in claim 3 of the present invention is that, after the formation of the dielectric film on the anode body, the fluororesin-based repellent is provided near the anode body side of the anode lead connecting the anode body and the anode terminal. The method according to claim 1, further comprising a step of forming a dried resin film by applying a liquid agent. The gist of the invention according to claim 4 of the present invention is that a step of forming the anode body by molding a fine powder of a valve action metal into a columnar shape, and one end face of the columnar body,
A step of sintering the column with the metal wire into a porous sintered body in a state where the metal wire to be the anode lead is erected, and a part of the anode lead, By applying a water repellent and drying, the step of forming the resin coating, on the surface of the anode body and the anode lead,
Along with forming the dielectric coating using an anodizing method, a manganese nitrate solution is immersed and thermally decomposed to form a manganese dioxide layer on the dielectric coating, or a chemical polymerization treatment is performed. Forming a conductive polymer layer, a step of forming an electrolyte layer, and a step of forming a conductive layer formed of a carbon layer, a silver paste layer, etc. on the electrolyte layer to form a cathode; 3. The method according to claim 2, further comprising the step of welding the anode terminal made of a solderable metal material to the anode lead to form an anode. The gist of the invention described in claim 5 of the present invention is that a metal wire to be the anode lead is erected on one end face of the column, and the column with the metal wire is sintered. The method according to claim 4, further comprising a step of forming a porous sintered body by heating. Further, the gist of the invention according to claim 6 of the present invention is a step of forming the anode body by molding a fine powder of valve action metal into a columnar shape,
Forming a porous sintered body by sintering the column with the metal wire in a state where the metal wire to be the anode lead is erected on one end surface of the column; Forming a porous sintered body, and then forming the dielectric coating on the surface of the porous sintered body by using an anodic oxidation method, and the anode lead having the dielectric coating formed on the surface. A step of forming the resin coating by applying and drying the fluororesin-based water repellent in the vicinity of the anode body side, and immersing and pyrolyzing a manganese nitrate solution on the dielectric coating. By forming a manganese dioxide layer, or, by performing a chemical polymerization treatment to form a conductive polymer layer, and a step of creating an electrolyte layer, on the electrolyte layer,
Forming a conductive layer composed of a carbon layer, a silver paste layer and the like to form a cathode; and forming an anode by welding the anode terminal made of a solderable metal material to the anode lead. 4. The method according to claim 3, wherein
In the method of manufacturing a capacitor. The gist of the invention according to claim 7 of the present invention is to form a resin coating film by applying a fluororesin-based water repellent obtained by adding a silicone resin at a predetermined mixing ratio to a part of an anode lead and drying the coating. A capacitor characterized by having a structure. Further, the gist of the invention described in claim 8 of the present invention is that, before forming a dielectric film on the anode body, the fluorine resin-based repellent is provided near the anode body side of the anode lead connecting the anode body and the anode terminal. The capacitor according to claim 7, further comprising a structure in which the resin coating film formed by applying a liquid agent and dried is provided. Further, claim 9 of the present invention
The gist of the invention described in is that after the formation of the dielectric film on the anode body, the fluorine resin-based water repellent was applied and dried in the vicinity of the anode body side of the anode lead connecting the anode body and the anode terminal, and dried. 8. The capacitor according to claim 7, wherein the capacitor has a structure in which the resin coating film is formed.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A feature of the present invention is that a fluorine resin-based water repellent (water repellent resin) is prepared by adding a silicone resin (water repellent resin) to a part of an anode lead (anode lead 2 described later) at a predetermined mixing ratio. ) Was applied and dried to form a resin coating (resin coating 3 described later). In particular,
Solid electrolytic capacitor (solid electrolytic capacitor 1 described later)
0) before the formation of the dielectric coating 4 on the anode body 1 (the first
(FIG. 1) or after the formation of the dielectric film 4 (second embodiment (FIG. 2) described later), an anode body (an anode body 1 described later) and an anode terminal (an anode terminal 7 described later). ) Is coated with a fluororesin-based water repellent to which a silicone resin is added at a predetermined mixing ratio in the vicinity of the anode lead (anode lead 1 described later) of the anode lead (anode lead 2 described later) and dried. It is characterized in that a resin coating film (resin coating film 3 described later) is formed. Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following, description will be given by taking the solid electrolytic capacitor 10 as an example of the capacitor of the present invention.

(First Embodiment) FIG. 1 is a cross-sectional view of a capacitor for explaining a capacitor manufacturing method and a capacitor according to a first embodiment of the present invention. In FIG. 1, 1 is an anode body, 2 is an anode lead, 3 is a resin coating, 4
Denotes a dielectric film, 5 denotes an electrolyte layer, 6 denotes a conductor layer, 7 denotes an anode terminal, and 10 denotes a solid electrolytic capacitor.

Referring to FIG. 1, a capacitor according to the present embodiment mainly includes an anode body 1, an anode lead 2, a resin coating 3, a dielectric coating 4, an electrolyte layer 5, a conductor layer 6, and an anode terminal 7. It is configured.

In the solid electrolytic capacitor 10 of the present embodiment, before forming the dielectric film 4 on the anode body 1, the anode lead 1 of the anode lead 2 connecting the anode body 1 and the anode terminal 7 is formed.
In the vicinity of the side, there is provided a structure in which a resin coating film 3 formed by applying and drying a fluororesin-based water repellent to which a silicone resin is added at a predetermined mixing ratio is formed.

Next, a method of manufacturing a capacitor according to the present embodiment will be described. Referring to FIG. 1, in the present embodiment, first, fine powder of a valve action metal such as tantalum, niobium, or aluminum is formed into a columnar shape (a cylinder, a prism, or the like) to obtain an anode body 1. At this time, the pillar (ie,
A metal wire to be the anode lead 2 is planted on one end face of the anode body 1), and the column with the metal wire is sintered to form a porous sintered body.

Next, a fluororesin-based water repellent to which a silicone resin is added at a predetermined mixing ratio is applied to a part of the anode lead 2 and dried to obtain a resin coating 3.

Next, the anode body 1 and the anode lead 2
A dielectric film 4 is formed on the surface of the substrate by using an anodic oxidation method. Then, a manganese nitrate solution is immersed and thermally decomposed on the dielectric film 4 to form a manganese dioxide layer, or a chemical polymerization treatment is performed to form a conductive polymer layer. Layer 5 is obtained. further,
A conductor layer 6 composed of a carbon layer, a silver paste layer, or the like is formed on the electrolyte layer 5 to form a cathode.

Thereafter, an anode terminal 7 made of a solderable metal material is welded to the anode lead 2 to form an anode.

As described above, according to the present embodiment, the silicone resin is added to the fluororesin-based water-repellent at a predetermined mixing ratio, applied on the anode lead 2 and dried to obtain the fluororesin-based water-repellent. This material alone is not sufficient for repeated immersion in chemicals and repeated heating during formation of the electrolyte layer 5 while ensuring the ease of application obtained from the thin film properties and non-adhesive properties that are the characteristics of the agent. The existing water and oil repellency and chemical resistance are complemented and improved by characteristics obtained from the chemical stability of the silicone resin.

As a result, the electrolyte layer 5 is not excessively formed on the resin coating 3, and electrical short-circuiting caused by the contact between the electrolyte layer 5 and the anode lead 2 can be prevented.

That is, even when the dimensions of the anode body 1 and the anode terminal 7 become shorter and shorter during the manufacturing process of the capacitor, the semiconductor base material which is considered to be a direct cause of the electric short circuit rises. It is possible to eliminate the occurrence of the phenomenon (the phenomenon of the electrolyte layer 5 (manganese dioxide or conductive polymer) creeping up on the anode lead 2), and as a result, a capacitor (particularly, a solid electrolytic capacitor using a valve action metal) 10) It is possible to achieve the effect of achieving a small size and a large capacity.

(Second Embodiment) FIG. 2 is a sectional view of a capacitor for explaining a capacitor manufacturing method and a capacitor according to a second embodiment of the present invention. The same parts as those already described in the first embodiment are denoted by the same reference numerals, and the duplicate description will be omitted.

In the first embodiment, the resin coating 3 is formed before the formation of the dielectric coating 4 by the fluororesin-based water repellent to which the silicone resin is added at a predetermined mixing ratio. It can be performed after the formation of the body coat 4.

Specifically, in the solid electrolytic capacitor 10 of the present embodiment, after the formation of the dielectric film 4 on the anode body 1, the anode lead 2 connecting the anode body 1 and the anode terminal 7 is on the anode body 1 side. In the vicinity, there is provided a structure in which a resin coating film 3 formed by applying a fluororesin-based water repellent to which a silicone resin is added at a predetermined mixing ratio and drying the coating is formed.

Referring to FIG. 2, in this embodiment, an anode body 1 and an anode lead 2 are provided in the same manner as in the first embodiment.
Is sintered into a porous sintered body, and then a dielectric film 4 is formed on the surface of the porous sintered body by using an anodic oxidation method.

Next, a fluororesin-based water-repellent to which a silicone resin is added at a predetermined mixing ratio is applied to a part (near) of the anode lead 2 having the dielectric coating 4 formed on the surface, and dried. Then, a resin coating film 3 is obtained.

Thereafter, similarly to the first embodiment,
An electrolyte layer 5 and a conductor layer 6 are formed as a cathode, and finally,
An anode terminal 7 made of a solderable metal material is welded to the anode lead 2 to form an anode.

As described above, in the present embodiment, in addition to the effects described in the first embodiment, at the time of forming the electrolyte layer 5, the resin coating 3 is peeled off from the anode lead 2,
Further, even when the electrolyte layer 5 is formed by entering the peeled portion, the anode lead 2 and the electrolyte layer 5 do not come into direct contact with each other because the dielectric film 4 is previously formed thereunder. There is an effect that an electrical short circuit can be prevented more than in the first embodiment.

It should be noted that the present invention is not limited to the above embodiments, and it is clear that the embodiments can be appropriately modified within the scope of the technical idea of the present invention. Further, the number, position, shape, and the like of the constituent members are not limited to the above-described embodiment, and can be set to numbers, positions, shapes, and the like suitable for carrying out the present invention. In each drawing, the same components are denoted by the same reference numerals.

[0030]

In the capacitor according to the present invention, a silicone resin is added to a fluororesin-based water repellent, applied on an anode lead and dried to obtain a thin film and a non-woven fabric characteristic of the fluororesin-based water repellent. This material alone was insufficient for the immersion in chemicals and repeated heating during the formation of the electrolyte layer, while ensuring the ease of application obtained from the adhesiveness. Is enhanced by characteristics obtained from the chemical stability of the silicone resin. As a result, there is an effect that the electrolyte layer is not excessively formed on the resin coating film, and an electrical short circuit caused by contact between the electrolyte layer and the anode lead can be prevented.

That is, even if the dimensions of the anode body and the anode terminal become shorter and shorter during the manufacturing process of the capacitor, the creeping-up phenomenon of the semiconductor base material which is considered to be a direct cause of the electric short circuit is obtained. The generation can be eliminated, and as a result, there is an effect that the capacitor can be reduced in size and capacity.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a capacitor for explaining a capacitor manufacturing method and a capacitor according to a first embodiment of the present invention.

FIG. 2 is a capacitor cross-sectional view for explaining a capacitor manufacturing method and a capacitor according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Anode body 2 ... Anode lead 3 ... Resin coating film 4 ... Dielectric coating film 5 ... Electrolyte layer 6 ... Conductor layer 7 ... Anode terminal 10 ... Solid electrolytic capacitor

Claims (9)

[Claims] A step of preparing a fluororesin-based water repellent in which a silicone resin is added to a part of the anode lead at a predetermined mixing ratio; A method for manufacturing a capacitor, comprising a step of forming a resin film by drying. 2. A method for forming a dielectric film on an anode body, comprising:
A step of applying the fluororesin-based water repellent and drying the resin coating film in the vicinity of the anode body side of the anode lead connecting the anode body and the anode terminal; 2. The method for manufacturing a capacitor according to item 1. 3. After the formation of the dielectric film on the anode body,
A step of applying the fluororesin-based water repellent and drying the resin coating film in the vicinity of the anode body side of the anode lead connecting the anode body and the anode terminal; 2. The method for manufacturing a capacitor according to item 1. 4. A step of forming the anode body by molding a fine powder of valve action metal into a columnar shape, and a state in which a metal wire to be the anode lead is erected on one end surface of the columnar body. In the step of sintering the columnar body with the metal wire to a porous sintered body, by applying and drying the fluororesin-based water repellent on a part of the anode lead, Forming a resin coating film, forming the dielectric coating on the surfaces of the anode body and the anode lead using an anodic oxidation method, immersing a manganese nitrate solution on the dielectric coating and heating the dielectric coating. A step of forming an electrolyte layer by performing a decomposition treatment to form a manganese dioxide layer or a chemical polymerization treatment to form a conductive polymer layer; and forming a carbon layer and a silver layer on the electrolyte layer. Form conductor layer composed of paste layer etc. A step of creating a cathode Te, the anode lead, the capacitor manufacturing method according to claim 2, characterized in that it comprises a step of creating an anode and welding the anode terminal made of solderable metal. 5. A step of implanting a metal wire to be the anode lead on one end face of the column, and sintering the column with the metal wire into a porous sintered body. The method for manufacturing a capacitor according to claim 4, further comprising: 6. A step of forming said anode body by molding a fine powder of valve action metal into a columnar shape, and a state in which a metal wire to be said anode lead is erected on one end surface of said columnar body. A step of sintering the columnar body with the metal wire to form a porous sintered body; and, after forming the porous sintered body, sintering the porous body using an anodic oxidation method. A step of forming the dielectric film on the surface of the resultant body, and applying and drying the fluororesin-based water repellent near the anode body side of the anode lead having the dielectric film formed on the surface. Forming a manganese dioxide layer by performing a manganese nitrate solution immersion process and a thermal decomposition process on the dielectric film,
Alternatively, a step of forming an electrolyte layer by forming a conductive polymer layer by performing a chemical polymerization treatment, and forming a conductor layer including a carbon layer, a silver paste layer, and the like on the electrolyte layer. 4. The method according to claim 3, further comprising: a step of forming a cathode by welding; and a step of forming an anode by welding the anode terminal made of a solderable metal material to the anode lead. 7. A capacitor having a structure in which a fluorine resin-based water repellent obtained by adding a silicone resin at a predetermined mixing ratio to a part of an anode lead is applied and dried to form a resin coating. . 8. Prior to forming a dielectric coating on the anode body,
In the vicinity of the anode body side of the anode lead connecting the anode body and the anode terminal, a structure is provided in which the resin coating film formed by applying and drying the fluororesin-based water repellent is formed. The capacitor according to claim 7. 9. After forming a dielectric film on the anode body,
In the vicinity of the anode body side of the anode lead connecting the anode body and the anode terminal, a structure is provided in which the resin coating film formed by applying and drying the fluororesin-based water repellent is formed. The capacitor according to claim 7.