US Patent 7812262 Multilayer printed circuit board

The objective of present invention is to provide an electroplating solution capable of forming the upper face of a via-hole and the upper face of a conductor circuit in the same layer in approximately the same plane at the time of manufacturing a multilayer printed circuit board. The electroplating solution of the present invention is characterized by containing 50 to 300 g/L of copper sulfate, 30 to 200 g/L of sulfuric acid, 25 to 90 mg/L of chlorine ion, and 1 to 1000 mg/L of an additive comprising at least a leveling agent and a brightener.