In the manufacturing process of copper base PCB, the discoloration of the copper base, which acts as a heat conductor, due to oxidation has always been a significant challenge. During production, if the copper base is not properly protected, it is highly prone to oxidation after passing through high-temperature processes like soldering ovens, leading to color changes that affect the product's appearance.
In light of this issue, PCBWay has decided to make OSP treatment the default process for all copper bases in future production. This decision aims to eliminate the negative effects of oxidation and discoloration through a standardized OSP process, thereby enhancing the product's appearance.
OSP (Organic Solderability Preservative) is an effective copper surface protection process. It forms a thin and uniform organic coating on the copper surface, preventing it from reacting with oxygen in the air, thereby avoiding oxidation and discoloration.
Through practical case analysis, it has been observed that copper base without OSP treatment exhibit noticeable oxidation and discoloration, turning red after exposure to high-temperature furnaces. The following figures illustrate this comparison. This oxidation-induced discoloration affects the visual appeal of the product.
Figure 1: Copper base without OSP after high-temperature furnace
Figure 2: Copper base with OSP after high-temperature furnace
In contrast, copper base treated with OSP maintain a good metallic luster under the same processing conditions, with little to no surface oxidation. This indicates that the OSP coating effectively protects the copper base surface at high temperatures, preventing oxidation reactions from occurring.
