| 摘要 |
PROBLEM TO BE SOLVED: To provide a copper foil for a printed wiring board particularly superior in soft etching property as well as resistance to heat discoloration, rust prevention capability, and solderability, and to provide a surface treatment method therefor. SOLUTION: The copper foil for the printed wiring board comprises a first layer consisting of 12-50 mg/m2 zinc layer containing 0.1-2.5 wt.% sulfur adhering on at least one side of a surface of the copper foil, and a second layer consisting of a chromate layer on the first layer, which is formed by means of adhering 0.5-2.5 mg/m2 chromium and 1.5-6 mg/m2 besides phosphor as required. The surface treatment method for the copper foil for the printed wiring board is characterized by forming the second layer consisting of the chromium by dipping the first layer into a solution containing a chromium compound, or a chromium compound and a phosphorus compound, and electrolyzing it as a cathode, after forming the first layer consisting of the zinc alloy layer containing the sulfur by dipping at least one side of the surface of the copper foil in a solution containing a zinc compound and a sulfur compound, and electrolyzing it as a cathode.
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