Metal foil for capacitor, solid electrolytic capactor using the foil and production methods of the foil and the capacitor

摘要

A metal foil for capacitor element is produced through a process comprising steps of etching and then electrochemically forming a metal foil after making cut lines each in a shape of a capacitor element with at least a part of a portion predetermined to be an anode-leading-out-part left uncut. The step of etching the foil is preferably performed with the anode-leading-out-parts being protected by protective material. Solid electrolytic capacitor elements prepared by using the metal foil have narrow variation in capacitance.