Patent ID: 11753733

Abstract:
In a method for producing high-purity electrolytic copper, a first additive (A) containing an aromatic ring of a hydrophobic group and a polyoxyalkylene group of a hydrophilic group, a second additive (B) formed of polyvinyl alcohols, and a third additive (C) formed of tetrazoles are added to a copper electrolyte, copper electrolysis is performed by controlling each concentration of the first additive (A), the second additive (B), and the third additive (C), a current density and a bath temperature, and accordingly, electrolytic copper in which a concentration of Ag is less than 0.2 mass ppm, a concentration of S is less than 0.07 mass ppm, a concentration of all impurities is less than 0.2 mass ppm, and an area ratio of crystal grains having an average crystal grain misorientation (referred to as a GOS value) exceeding 2.5° is 10% or less is obtained.