(1) Pretreatment of FPC soft board plating
　　 The surface of the copper conductor exposed by the flexible printed board FPC after the coating process may be contaminated by adhesive or ink, and there may be oxidation and discoloration caused by the high temperature process. In order to obtain a tight adhesion with good adhesion, it is necessary to Contamination of the conductor surface and removal of the oxide layer clean the conductor surface. However, some of these pollutions are very strong in combination with copper conductors, and they cannot be completely removed with weak cleaning agents. Therefore, most of them are often treated with a certain amount of alkaline abrasive and brushing. The covering adhesives are mostly rings. Oxygen resin and poor alkali resistance, which will lead to a decrease in bonding strength. Although it is not obvious, in the FPC plating process, the plating solution may infiltrate from the edge of the coating layer, and in severe cases, the coating layer may be peeled off. .
　　 (2) Thickness of FPC soft plate plating
　　 During electroplating, the deposition rate of electroplated metal is directly related to the electric field strength. The electric field strength changes with the shape of the line pattern and the positional relationship of the electrodes. Generally, the thinner the line width of the wire, the sharper the terminal of the terminal part, and the distance from the electrode. The closer the electric field is, the thicker the coating will be. In the applications related to flexible printed boards, the difference in the width of many wires in the same line is extremely large, which makes it more likely to cause uneven thickness of the plating layer. To prevent this from happening, a shunt cathode pattern can be attached around the line. Absorbs the uneven current distributed on the plating pattern to maximize the uniform thickness of the coating on all parts. Therefore, it is necessary to work on the structure of the electrode.
　　 (3) Smudges and dirt on FPC soft board plating
　　 The plating state just after plating, especially the appearance, is not a problem, but some surfaces will appear stains, dirt, discoloration, etc. in the near future, especially when the factory inspection does not find any abnormality, but when the user receives the inspection, Found that there are appearance problems. This is caused by insufficient drift, and a residual plating solution on the surface of the plating layer, which is caused by a slow chemical reaction over a period of time. In particular, the flexible printed board is not very flat due to its softness, and the recess is easy to accumulate in various solutions, and then reacts and discolors at the portion. In order to prevent this from happening, not only full drift but also full drifting is required. Perform adequate drying. It is possible to confirm whether or not the drift is sufficient by a heat aging test at a high temperature.