After the plating solution using electroplating additives is used for a certain period of time, excess additives or decomposition products will accumulate, forming organic impurities in the plating tank, which will cause harm to electroplate. Therefore, the organic impurities in the plating tank should be treated regularly. When the coating is very bright, but the dispersing ability is not good, and it is easy to peel, and even cracking occurs in the high current area, it is mostly the performance of organic impurities, but in the actual processing process, if the method is not appropriate, it will be difficult to completely remove the organic excess.
Some processors have done everything that the processing technology requires, but they have not done the idea. The main point is that the plating solution should not be heated first, it should be treated with hydrogen peroxide, then heated, and then treated with an appropriate amount of activated carbon. When the amount of organic impurities is large, potassium permanganate should be used for treatment. At this time, the pH value should be adjusted to 3, and then heated to 60-80 °C, and the pre-dissolved potassium permanganate should be added in dosage within 0.3-1.59/L. After vigorous stirring, let it stand for more than 8 hours, and then adjust after filtration. pH to the normal range. If the plating solution is red, it can be removed with hydrogen peroxide.
In addition, there is a type of organic pollutants that cannot be removed by the above method. For example, the organic impurities of animal glue, the dissolution of wax prototypes, etc. The content of such impurities is only 0.01 ~ O.19/L, which will cause the coating to peel and so on. At this time, 0.03-0.059/L of tannic acid should be added to the plating solution, and flocs will appear after about 10 minutes, and can be removed after sufficient precipitation for more than 8 hours. It is best to carry out this treatment together with the treatment of activated carbon, which can completely remove the pollution of all organic impurities.
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