KR20020009967A - Manufacture of electrolytic capacitor using conducting polymer-Improvement of impregnation of oxidant solution for chemical oxidative polymerization - Google Patents

Abstract

PURPOSE: A conductive polymer solid electrolytic capacitor is provided to improve capacity of the condenser by uniformly distributing oxide film all over the condenser. CONSTITUTION: A chemical polymerization tank(30) contains an oxidant solution(34), and an element(38) fixed to an end of a lead frame(40) is dipped into the oxidant solution for a predetermined time period. The oxidant solution is produced by mixing the solvent of 5 to 40 percent with respect to the total volumetric ratio of the solvent, wherein the solvent has volatility higher than that of water and a surface tension lower than that of water. As the solvent, acetone, acetonitrile, methanol or ethanol is used. The oxidant is used for polymerization of the monomer.

Description

Manufacture of electrolytic capacitor using conducting polymer-Improvement of impregnation of oxidant solution for chemical oxidative polymerization}

The present invention relates to a conductive polymer solid electrolyte capacitor prepared by improving the impregnation of the oxidizer, and more specifically, the oxidizer solution is 5 to 40% of the solvent is more volatile than the water such as acetone, acetonitrile, methanol, ethanol and surface tension The present invention relates to a conductive polymer solid electrolytic capacitor through the oxidizing agent impregnation, which is prepared by mixing the small solvent and improving the impregnation rate of the device to improve the capacity.

The general process for producing a tantalum solid electrolytic capacitor is performed in the order of a valve metal → chemical conversion → chemical polymerization → electrolytic polymerization → carbon / silver coating → lead frame welding → resin molding.

In particular, when the tantalum solid electrolytic capacitor is manufactured, a molding process is performed and then a chemical conversion process is performed. The device sintered body is impregnated with an oxidant solution of a chemical polymerization reactor to form a thin film having a constant thickness on the surface of the device sintered body. Since it is a factor that determines the capacity of the characteristics of the solid-state electrolytic capacitor, the film-forming work of the conductive polymer layer for the device is of paramount importance.

In the case of manufacturing a general solid electrolytic capacitor, in general, first formation of a valve metal such as tantalum and aluminum (oxide formation) → second oxidizing agent Impregnation → third electrolytic polymerization or first and second repetition → fourth carbon, silver paste application → fifth assembly (lead frame welding, molding, etc.) process.

1 is a view illustrating a state in which a solid electrolyte capacitor is impregnated into an oxidant solution when a solid electrolyte capacitor is manufactured. An oxidant solution 12 is loaded in the chemical polymerization reactor 10, and the oxidant solution 12 The chemical element 14 fixed to the end of the lead frame 16 is impregnated for a predetermined time.

The state in which oxide is coated on the outer circumferential surface of the chemical conversion element 14 is a portion indicated by a dotted line in the upper direction of the arrow, which shows the state in which the oxide film is coated by electrolytic polymerization. Forming a conductive polymer layer on the substrate has the best effect on quality.

As described above, ammonium persulfate or iron chloride (Fecl ₃ ) was dissolved in water and used as an oxidant solution as an oxidant solution used in the manufacture of a conventional solid electrolyte capacitor. (In particular, tantalum elements using high CV powders) impregnation is not performed properly, which results in a problem that the capacity characteristics of the finished solid-state electrolytic capacitors are deteriorated.

In order to solve the above-described problems, the conductive polymer solid electrolyte capacitor through the oxidant impregnation improvement of the present invention, when preparing the oxidant solution is more volatile and less surface tension than water, such as acetone, acetonitrile, methanol, ethanol Since the solvent is manufactured by mixing 5 to 40% of the solvent (volume ratio), the purpose of the present invention is to improve the capacity characteristics of the completed solid electrolytic capacitor by uniformly and smoothly forming oxides when impregnated with the oxidant solution. It is done.

In order to achieve the above object, the present invention is a conductive polymer solid electrolyte capacitor which forms a conductive polymer by impregnating a chemical element into an oxidant solution, wherein the chemical element is impregnated in an oxidant solution of a chemical polymerization reactor. The oxidant solution to be used is prepared as a mixed solution prepared by mixing 5 to 40% (volume ratio) of the total volume ratio of the solvent by using a solvent having a higher volatility and a smaller surface tension than water such as acetone, acetonitrile, methanol, and ethanol. It provides a conductive polymer solid electrolytic capacitor through the improved oxidant impregnation using the made.

1 is a view illustrating a state in which a solid electrolyte capacitor is impregnated into an oxidant solution when a solid electrolyte capacitor is manufactured.

2 is a view for explaining a state of impregnating a solid electrolyte capacitor in the oxidant solution of the present invention when manufacturing a conductive polymer solid electrolyte capacitor.

<Brief description of symbols for the main parts of the drawings>

30: chemical polymerization reactor 34: oxidant solution

38 element 40 lead frame

Hereinafter, with reference to the accompanying drawings will be described the configuration and operation state of the present invention.

2 is a view for explaining a state of impregnating a solid electrolyte capacitor in the oxidant solution of the present invention when manufacturing a conductive polymer solid electrolyte capacitor, in the present invention is a chemical solid by chemical conversion (oxidant impregnation + monomer impregnation) → electrolytic polymerization An electrolytic capacitor is produced.

An oxidant solution 34 is loaded into the chemical polymerization reactor 30, and the oxidant solution 34 is impregnated with a chemical conversion element 38 fixed to the end of the lead frame 40 in the internal solution for a predetermined time. .

In particular, the oxidant solution 34 is prepared as a mixed solution. The oxidant solution 34 is a solvent having a higher volatility and a smaller surface tension than water, such as acetone, acetonitrile, methanol, and ethanol, based on the total volume ratio of the solvent. It is prepared by mixing 5 to 40% (volume ratio), and the oxidizing agent is used to polymerize a monomer (pyrrole) into a polymer during chemical polymerization.

An oxide film is coated on the outer circumferential surface of the converted device 38. The part indicated by the dotted line in the upper direction of the arrow shows the state in which the oxide film is coated on the converted device 38.

As can be seen from the above description, when the oxide film is formed on the outer circumferential surface, the oxidant solution 34 includes a solvent having a higher volatility and a lower surface tension than a solvent such as acetone, acetonitrile, methanol, and ethanol. It is manufactured by mixing 5 to 40% (volume ratio), so that impregnation is much better than aqueous solution, and the amount of droplets formed on the surface of the chemical element after the impregnation of the chemical element with the oxidant solution is too small, resulting in excessive polymer generation only on the surface of the chemical element Problems can be prevented.

The effects of the configuration and operation state of the present invention described above will be described.

The present invention is prepared by mixing an oxidant solution, and the oxidant solution is impregnated with the chemical element therein, so that the oxide film can be evenly distributed on the outside of the chemical element, thereby improving the capacity realization rate for the element. Can be obtained.

In particular, the oxidant solution is prepared by mixing 5 to 40% (volume ratio) of the total volume ratio of the solvent by using a solvent having a higher volatility and a smaller surface tension than water such as acetone, acetonitrile, methanol, and ethanol. Since the amount of droplets formed on the surface of the chemical element after the impregnation of the solution is small, it is possible to obtain an effect of preventing the formation of excessive polymer only on the surface of the chemical element, and in particular, when the element is impregnated while depressurizing the oxidant solution, While acetonitrile, methanol, and ethanol, which were naturally impregnated and more easily impregnated, may be volatilized and removed to obtain an effect of improving impregnation characteristics.

Claims (1)

In a conductive polymer solid electrolytic capacitor which forms a conductive polymer by impregnating a chemical element into an oxidant solution, an oxidant solution (34) used by impregnating the chemical element (38) in the oxidant solution (34) of the chemical polymerization reactor (30). ) Is prepared by using a mixed solution prepared by mixing a solvent such as acetone, acetonitrile, methanol, ethanol, etc. so as to have a volume ratio of 5 to 40% (volume ratio) by using a solvent having a higher volatility and a smaller surface tension. Conductive polymer solid electrolyte capacitor through the oxidant impregnation to improve.