The leveling agent, as a core functional additive in the coating formula, regulates surface tension and improves fluidity, thereby addressing defects such as brush marks, orange peel, and pinholes that occur during construction. It is the "backstage hero" that ensures the smoothness and flatness of the coating film. Its unique amphiphilic structure can form stable molecular layers at the interface between the coating and the substrate, air, and eliminate surface tension gradients, promoting uniform coating spread and tight film formation. 
The mainstream products are divided into three categories: The organic silicon type, with its low surface energy advantage, enhances the smoothness and scratch resistance of the coating film, and is widely used in solvent-based and water-based coatings; The acrylic type has strong compatibility and also has degassing and defoaming functions, suitable for primers, topcoats, and powder coatings in multiple scenarios; The fluorocarbon compound type is highly efficient but has a high cost, mostly used in special occasions with extremely high smoothness requirements. 
Under the background of tightened environmental policies and the green transformation of coatings, the leveling agent market continues to expand. In 2023, the global market size reached 2.86 billion US dollars, with China's consumption exceeding 68,000 tons, and an average annual growth rate of 8%-9%. The increase in the proportion of water-based coatings has driven the development of low-VOC and high-compatibility products as the research and development focus, and the demand for high-end types such as polyether-modified organic silicon has increased significantly. 
In the future, the leveling agent will develop towards functional compounding, environmental protection, and customization. New technologies such as nano-modification and biobased materials will accelerate their implementation, and its application will continue to deepen in fields such as automobiles, construction, and electronics, providing key support for the high-quality development of the coatings industry.