Some basic methods to prevent blackening of aluminum paste

Aluminum silver paste additive; anti-blackening, loss of light, back-thick aluminum silver paste products, due to excellent light reflection ability and metallic luster, the paint film has obvious "flop effect", the decorative effect is gorgeous and beautiful, so Automotive coatings, metal industrial coatings, marine coatings, heat-resistant coatings, etc. have a wide range of applications. However, aluminum silver paste is easily oxidized or contaminated during the production process, resulting in blackening and loss of light.

Mainly in the following aspects:

Pollution. Aluminium silver paste is susceptible to contamination during screening or other processes, or other metal impurities cause the product to become black and lose light.

Oxidation. Aluminum silver paste is easily oxidized, vulcanized or alcoholized during the production process, which causes the product to blacken and affect the appearance of the paint film. 3. Other additives. Due to the addition of dispersants or other additives containing double bonds, aerobic polymerization occurs under the action of oxygen to cause the aluminum silver paste to appear coarse.

In addition to the above aspects, there are also other causes of blackout. Our recommended aluminum aging solution is to use phosphite antioxidants to prevent free radical polymerization while sequestering impurity metal ions to prevent oxidative discoloration. Moreover, the antioxidant has a low acid value and has no effect on the system. Of course, the method of adding an antioxidant cannot fundamentally solve the problem of discoloration, but within a certain range, it can effectively prevent blackening, loss of light and coarseness, maintain product gloss and improve storage stability. In the process of production and storage, the contact with oxygen should be isolated as much as possible to avoid oxidation of the aluminum paste.

In general, preventing the aging of the oxygen and harmful polymerization can improve the quality of the aluminum paste to some extent.