The reason why the coating is white red and bright around the concave hole during the application of Pyrophosphoric acid copper brightener

The reason why the coating is white red and bright around the concave hole during the application of Pyrophosphoric acid copper brightener

Sat Jun 17 15:48:29 CST 2023

In the process of using Pyrophosphoric acid copper brightener, sometimes the coating appearance of the workpiece produced is white red and shiny around the concave hole. What is the reason?

Based on field experience and the characteristics of the product Pyrophosphoric acid copper brightener Cu-203, Bigley Technology has made analysis, mainly including the following three points:

1. The ratio of total pyrophosphate to copper ion (P2O74-/Cu2+) in the plating solution is too high, and the concentration of free complexing agent is too high. A suitable amount of copper salt should be added to the plating solution to reduce the ratio within the range of 6.4 to 7.5, and the color of the coating will return to normal.

2. The current density at work is too high. When the current density is too high, it can also cause the workpiece coating to turn white red. At this point, the working current should be appropriately reduced to restore normal operation.

3. Adding too much NH4+to the plating solution can cause brightness around the concave holes of the workpiece. This situation can be adapted to increasing the temperature of the plating solution to the upper limit. For example, using a Cu-203 plating solution can increase the temperature to 60 ℃, gradually reducing the amount of ammonia and slightly reducing the current. After a period of production, the coating will return to normal.

Therefore, during the use of Pyrophosphoric acid copper brightener, the coating appearance of the workpiece is white red, and the above three points should be noted when the surface around the concave hole is bright, so as to eliminate the fault in time. If you are interested in the additive of coke Copper(II) phosphate, please contact Bigley customer service to obtain free samples and detailed technical information!

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