1. Controlling the particle size distribution is crucial for achieving optimal results, with a narrower range being ideal. Achieving precise control over powder particle size can be challenging, but in our production process, we primarily focus on adjusting the speeds of the primary and secondary grinding stages in the ACM machinery. The key particle size target is between 40-50 micrometers, and it’s best if the distribution remains as tight as possible.
2. Enhancing resin content is another important consideration. By increasing the amount of resin and reducing the quantity of fillers, we can optimize the formulation. Choosing a resin with excellent charging properties is essential, and epoxy-based resins tend to perform better in powder coatings. Some manufacturers struggle with creating polyester powders, as they can be more difficult to formulate. The quality of the spray application also varies depending on the equipment used—friction spray guns generally provide superior coverage compared to electrostatic guns, allowing for thicker coatings without noticeable orange peel effects or other imperfections.
3. Selecting the appropriate filler is equally significant. The fineness and dispersibility of the filler directly impact the final powder product. Precipitated powders often outperform standard ultrafine helium varieties, while barium sulfate tends to offer better performance than calcium carbonate in many applications.
4. Incorporating the correct amount of charging aids within the formulation is beneficial. These additives enhance the powder's ability to hold an electrical charge, which is particularly useful in areas near the high-voltage electrostatic spray gun where strong electric fields exist. When the air becomes ionized, creating millions of ions, the charged particles become polarized as they pass through this zone. This polarization helps capture additional negative ions, enabling the particles to carry a stronger charge. This is especially advantageous for hard-to-reach areas like grooves, where the electric field is weaker due to the Faraday cage effect. Powders with enhanced charge capabilities can reach these regions independently, thereby improving overall coverage and quality of the coating.
Heilongjiang Junhe Building Materials Technology Co., Ltd , https://www.junhejiancai.com