Patent ID: 6444112
Filing Date: 2002-09-03
Classification: C25D,H05K

Abstract:
A process for producing an electrodeposited copper foil from an electrolyte containing copper sulfate dissolved therein, in which said electrolyte contains a small amount of lead (Pb) ions, said process comprising the steps of adding a salt of a metal of Group IIA of the periodic table to the electrolyte in an amount of 10 to 150 mols per mol of lead (Pb) ions contained in the electrolyte, reacting the lead (Pb) ions contained in the electrolyte with the metal of Group IIA of the periodic table to thereby form an insoluble composite substance, precipitating and removing said insoluble composite substance from the electrolyte and electrodepositing a copper foil from the electrolyte having the lead (Pb) ions removed therefrom.