Method of producing electrolytic copper foil and apparatus for producing same

摘要

In a method of producing an electrolytic copper foil by passing an electrolyte between a rotating cathode drum and anode located opposite to the cathode drum, the thickness of the resulting copper foil is made uniform throughout. The anode has a structure including a main portion and an end portion, the end portion being divided widthwise into n foil thickness-uniformizing sub-anodes. Electricity is supplied to the main anode and the sub-anodes at a preset current density D (A/dm2) to attain a target foil thickness T (g/m2). Variations of thickness in the direction of the width of the resulting copper foil are measured as the thicknesses Tm (g/m2) where m=1-n in the direction of the width of the copper foil corresponding to the n sub-anodes, and the quantities of electricity being supplied to the n sub-anodes are individually controlled at current densities Dm (A/dm2) where m=1-n so that Tm values are made equal to the target foil thickness T (g/m2). Alternatively, a pattern of thickness deviations of a copper foil produced per revolution of the cathode drum is divided into m sections where m=1-n widthwise and k sections lengthwise, the foil thicknesses Tm-k (g/m2) where m=1-n of the m xk sections corresponding to the angle of rotation from a reference point of the cathode drum as determined by an encoder are measured, and the quantities of electricity supplied to the n sub-anodes at current densities Dm-k (A/dm2) where m=1-n are controlled individually correspondingly to the angle of rotation from the reference point of the cathode drum so that Tm-k becomes equal to the target foil thickness T.