Can You Tell the Difference Between Epoxy Zinc Rich Primer and Epoxy Zinc Phosphate Primer?

Many customers often have this question when buying paint: What is the difference between the same epoxy primer, epoxy zinc rich primer and epoxy zinc phosphate primer?

1. The anti-corrosion focus of epoxy zinc rich primer and epoxy zinc phosphate primer is different

The main difference between the two is the difference in anti-corrosion and anti-rust effects.

The epoxy zinc rich primer is mainly chemical anti-corrosion and anti-rust, and has a corrosion inhibition effect; while the epoxy zinc phosphate primer is mainly corrosion and anti-rust and has a shielding effect.

2. The anti-rust principles of epoxy zinc rich primer and epoxy zinc phosphate primer are different

Epoxy zinc rich primer: Zinc powder is used as the main anti-rust pigment, and the zinc powder sacrifices cations to perform cathodic protection, corrosion inhibition and shielding of the metal iron with triple anti-rust functions. Zinc powder is corroded earlier than steel, and complexes are formed, which can shield and inhibit corrosion and protect steel from corrosion.

Epoxy zinc phosphate primer: zinc phosphate is used as the main anti-rust pigment. Its anti-rust principle is to generate adhesion and corrosion-inhibiting complexes through hydrolysis reaction, so that the surface of the metal substrate is phosphatized to form an effective protective layer in the anode range, which has a good corrosion inhibition and shielding effect, and isolates the corrosive medium. erosion.

3. The substrate treatment of epoxy zinc rich primer and epoxy zinc phosphate primer is different

Epoxy zinc rich primer: The requirements for the surface treatment of the substrate are relatively strict. If sandblasting is used, it must meet the rust removal standard Sa2.5 or above.

Epoxy zinc phosphate primer: The treatment requirements for the substrate are lower. You only need to clean the substrate to ensure that there is no rust, oxide scale, and oil stains, and it can also achieve a certain anti-corrosion and anti-rust function.

4. The application environment of epoxy zinc rich primer and epoxy zinc phosphate primer is different

Epoxy zinc rich primer: suitable for anti-corrosion coating of steel structures in harsh atmospheric environments. For example: anti-corrosion coating for marine facilities, port facilities, bridges, pipelines, storage tanks, and mechanical equipment.

Epoxy zinc phosphate primer: suitable for anti-corrosion coating under ordinary atmospheric environment. For example: anti-corrosion coating of mechanical equipment, storage tanks, engineering facilities, pipelines, etc. Especially for the rust protection of steel structures indoors and outdoors or in humid environments.