A customer inquired that during the production process of using acidic copper plating brighteners, sometimes the brightness of the acid copper coating is relatively poor. So what is the reason that affects the brightness of the coating?
Based on on-site experience and the characteristics of the acidic copper plating brightener Cu-510, Bigley Technology analyzed that there are many factors that affect the brightness of the acid copper coating, mainly including the following five factors:
1. The raw materials used are impure, that is, the copper sulfate and sulfuric acid used in our acid copper plating solution during tank preparation are impure. If impure sulfuric acid is introduced, it will bring in more iron and organic impurities. If the plating solution is not treated in a timely manner, the acid copper layer will not shine.
2. Consumption of brightener. In acid copper plating solution, the factors that affect the normal consumption of brighteners include the type, shape, surface state of the workpiece, the concentration of copper sulfate, and the influence of impurities. During the production process, in addition to following the instructions for normal use, we also need to add brighteners based on production experience. For example, the consumption of brighteners varies depending on the temperature and current of the plating solution.
3. Concentration of chloride ions. When there are no chloride ions in the acid copper plating solution or the concentration of chloride ions is too low, the leveling performance of the coating is poor, and it is prone to blooming and tarnishing; When the concentration of chloride ions is too high, the brightness of the acid copper coating is poor, and it is also prone to dendritic stripes, and the consumption of brightener is high.
4. The influence of monovalent copper. The presence of monovalent copper ions in acid copper plating solution can cause the coating to be not bright. Due to the preferential precipitation of monovalent copper over divalent copper during the deposition of the coating, it is easy for the coating to exhibit roughness, burrs, and low current areas that are not bright.
5. Copper anode passivation. Due to the presence of anode copper powder and monovalent copper in the plating solution, when the anode current density is too high or the phosphorus content of the copper anode is not suitable, the anode will be passivated, causing the coating to be not bright.
Therefore, in the production process of using acidic copper plating brighteners, we should pay attention to the above 5 points, and control the main salt composition and brightener concentration to avoid poor brightness of the coating and reduce the occurrence of faults. If you are interested in acidic copper plating brighteners, please contact Bigley customer service for free samples and detailed technical information!
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