METHOD FOR MANUFACTURING ELECTROLYTIC COPPER FOIL, ELECTROLYTIC COPPER FOIL, COPPER-CLAD LAMINATE AND PRINTED CIRCUIT BOARD

摘要

PROBLEM TO BE SOLVED: To provide a method for effectively preventing the coprecipitation of Pb fine powder at the time of depositing electrolytic copper foil from an electrolytic solution in which copper sulfate is dissolved by using a cylindrical drum as a cathode and to furnish the electrolytic copper foil substantially free from Pb fine powder (including lead oxide) and a printed circuit board with a desired pattern formed by using such electrolytic copper foil. SOLUTION: The salts of group IIA metals such as calcium carbonate and barium carbonate are added by 10-150 mols per mol of Pb ions to remove Pb ions from the electrolytic solution as a precipitate, and the resultant electrolytic solution is used to form electrolytic copper foil. Meanwhile, the copper-clad laminate is formed by laminating the electrolytic copper foil on at least one side of an insulating substrate, and the printed circuit board is obtained by forming a desired pattern by using the electrolytic copper foil of the copper-clad laminate.