JPS60123018A - Method of producing sintered electrolytic condenser - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for manufacturing a sintered electrolytic capacitor.

Conventional configuration and problems Generally, in a sintered electrolytic capacitor, a molding material consisting of a powdered anode material and a binder is put into a mold, high pressure is applied and pressure molded to obtain a molded body, and then, It was obtained through processes such as sintering, forming a dielectric layer, and forming a cathode part. However, with these conventional powder metal construction methods, if the molding die, molding conditions, etc. are not precisely controlled, the molded product may crack, causing density unevenness, etc., and reducing the product yield.0 These drawbacks In order to improve this, many improvements were made to the material composition, molding mold, molding conditions, etc., and a molding method using an organic polymer material as a binder was devised.

However, products that have been molded using an organic polymer material as a binder and then subjected to processes such as debinding and sintering under normal conditions will discolor due to oxidation in the air once the binder is removed, especially capacitors using tantalum. In the case of a sintered body such as, the leakage current may become high, which may cause problems.

As a result of intensive research to solve these problems, we discovered that these problems can be solved by controlling the debinding conditions of the binder containing organic polymer materials, lubricants, water, etc.The details are as follows. I will explain.

Purpose of the Invention The present invention provides a method for producing an inexpensive and high-quality sintered electrolytic capacitor by eliminating the oxidation phenomenon that occurs when the conventional molded body using an organic binder is removed from the binder in a heat to oxygen atmosphere. It is something.

Structure of the Invention The structure of the present invention is to mold a powdered anode material into a predetermined shape by using a kneaded material with a binder consisting of a cellulose compound and other additives, and then heat the mixture in an argon gas or helium gas atmosphere. The process consists of thermally decomposing the binder and then sintering it at a predetermined temperature.Description of Examples Examples 1 to 8 Tantalum powder for capacitors 83 wt%, 20'
The viscosity of 2% methylcellulose aqueous solution in C is 30o
2-5 wt% methylcellulose of O ~ 5000 cps.

A kneaded product was obtained by adding 2.5 wt% of glycerin and 12 wt% of water. Using this kneaded product, an extrusion molded product having a diameter of 0.9 mm was obtained. This molded body was cut into a predetermined length, and the diameter was 0.
．． A 2 mm tantalum wire was inserted to obtain a molded article with tantalum wire attached. The molded body was thermally decomposed under the conditions shown in Table 1 (thermal decomposition temperature of cellulose in air is 290 to 350 °C
) and sintered at 1600'C, followed by a general tantalum capacitor manufacturing process to obtain a product. Table 2 shows the results of measuring the characteristics of this product. (In Table 2, □lo ~ 121 and 2'' decay:) Table 1 Table 2 Reference example 1 A powder molding composition consisting of tantalum powder for capacitors, camphor, additives, etc. Table 1 shows the characteristic values of tantalum capacitors obtained using the traditional tantalum capacitor manufacturing method.

Table 3 Effects of the Invention According to the present invention, as is clear from the results in Table 22 and Table 3, thermal decomposition is carried out in an atmosphere of inert gases such as argon and helium. It showed excellent characteristic values. Furthermore, the higher the thermal decomposition temperature, the better the results.

It is in the state of pure tantalum without any further formation.
Also, the fact that the thermal decomposition temperature is better on the high temperature side is that
It is thought that this is because the decomposition power of organic matter in XF-MOE2P was in a carbonized state and no residue remained.

Good results can be obtained by setting the thermal decomposition temperature to a temperature higher than the decomposition temperature of the binder used in air, but the most preferable value is about twice or more.

Claims (1)

[Claims] 1) Powder anode material for electricity storage device, organic polymer material, lubricant,
a step of processing a mixed material made of water into a predetermined shape; a step of removing the binder by thermal decomposition in an inert gas atmosphere at a temperature higher than the thermal decomposition temperature in air; 02) A method for manufacturing a sintered electrolytic capacitor according to claim 1, wherein the powder anode material for a capacitor is tantalum. ) The method for manufacturing a sintered electrolytic capacitor according to claim 1, wherein the inert gas is argon or heliumra gas.