The leveling principle of silicone leveling agent: Surface tension is the main driving force for coating film leveling, but poor surface tension is the main source of surface defects on the coating film. Increasing the surface tension of the coating film to achieve a surface tension balance, which is very beneficial to the flow and leveling of the coating film, but it cannot. Therefore, people have to reduce the surface tension of the coating film to eliminate the difference in surface tension, control the surface state of the coating film, and eliminate surface defects.