Electrolytic copper foil
AssigneeJX Nippon Mining & Metals Corporation
InventorMichiya Kohiki
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Abstract
Provided is an electrolytic copper foil having a surface roughness Rz of 2.0 μm or less, wherein a foil thickness difference in the width direction is 1.5% or less. Also provided is the electrolytic copper foil, wherein the foil thickness difference in the width direction is 1.3% or less. Further provided is the electrolytic copper foil, wherein a variation in the roughness in the width direction (Rzmax−Rzmin)/Rzavg is 15% or less. An object of the present invention is to provide an electrolytic copper foil having low surface roughness, wherein the formation of an “elongation wrinkle” and a discolored streak along the length direction is suppressed by allowing the thickness to be uniform in the width and length directions.
Claims10
An electrolytic copper foil having a surface roughness Rz of 2.0 μm or less, wherein a foil thickness difference among sixteen places in a width direction is 1.5% or less, the electrolytic copper foil is cut at both ends in the width direction by 20 mm and folded four times and divided into sixteen to measure the foil thickness difference in the width direction, no discolored streak is present along a length direction on a surface of the copper foil, and an elongation wrinkle is not developed.
A method of manufacturing an electrolytic copper foil, comprising the steps of:
- flowing a copper electrolytic solution between a rotating cathode drum and an anode opposed to the cathode drum to allow copper to be electrodeposited on a surface of the cathode drum;
- providing a supplementary split anode only along a front side of the drum;
- individually controlling an amount of electricity provided to each of a plurality of split anodes of the supplementary split anode, the plurality of split anodes being separated in a width direction of the drum;
- and
- detaching an electrodeposited copper foil from the cathode drum.
Dependencies are inferred from the claim text.