| 摘要 |
PURPOSE:To use a metallic wire made of a metal other than tantalum as the lead wire of a capacitor element of tantalum solid electrolytic capacitor by applying in advance an insulating material to the part to be dipped in a chemical conversion liquid of the lead wire of the chip piece of the element formed by sintering tantalum powder. CONSTITUTION:Tantalum power is compacted into a porous chip 11 and then sintered. A lead wire 12 is fixed to one end face 11a of the chip 11. Then, an insulating material 15 such as the heat-resistant synthetic resin or glass is applied to the fixed end of the wire 12 and dried. After drying, a dielectric film 13 composed of tantalum pentoxide is formed on the surface of each tantalum particle in the chip 11 by subjecting the tantalum to anodic oxidation by making a direct current to flow between the wire 12 and a chemical conversion liquid A while the chip 11 is dipped in the liquid A so that the liquid A can spread itself into the chip 11. Therefore, the manufacturing cost of a capacitor element for tantalum solid electrolytic capacitor can be reduced, since an inexpensive metallic wire can be used as the lead wire of the capacitor element. |
