Anti-Corrosive Primer

Anti-corrosive primer is used on steel and other metallic products to prevent oxidation and corrosion. There are many kinds of primer, all of which cannot be fully listed here.

Most of the primer bases are alkyd resin, phenolic resin, chlorinated rubber, epoxy resin, vinyl resin, ethyl silicate. These are mixed with anti-corrosive pigments, such as ferric oxide, MIO, alumina powder, alumina paste, zinc powder, red lead, zinc chromate, zinc phosphate, aluminum tripolyhosphate, PbO, and others. The anti-corrosive effect depends on the types of resin, anti-corrosive pigments, adhesiveness, and other features.

The drying time of the primer, which depends on the type of resin, can range from one to eight hours. The thickness of the painted film also influences the drying time. In addition, the middle or topcoat used on the primer should be compatible with the primer. (The compatibility of the paint must be checked.) A wrong choice may result in cracks, wrinkles, blisters, lifting, and the inability to dry properly. The basic principle of choosing the primer and the middle or topcoat is that they should belong to the same resin system; or the solubility of thinner in the middle or topcoat must be weaker than the primer.