The coating of the Powder coating depends on the flow of the resin in the molten state and adhesion to each other, and the melt viscosity is high, which limits the free flow of the melt. It has been the focus of the Powder coating industry to improve the leveling of Powder coatings and form a good film. Therefore, it is of great practical significance to discuss the factors that affect the leveling of Powder coatings, to optimize the formulation design, to improve the equipment and construction technology, to improve the appearance of Powder coatings.
1 leveling mechanism
Powder coating is a solvent free uniform system, must be melted in order to adhere to the coated above, after the flow into a film, generally need to go through three processes:
(1) from a single powder particle, it becomes a continuous, uneven film, which is called the aggregation process;
(2) the formation of a smooth and smooth surface from a continuous uneven surface, that is, the flow process;
(3) through the cross-linking reaction, the viscosity of the melt is increased continuously, and finally solidified into a hard coating.