The role of hydroxypropyl cellulose (HPMC) in alcohol-based coatings has the following aspects: One, increase the viscosity and rheology of the coating: HPMC is a highly water-absorbing polymer that can absorb a large amount of water molecules to form colloidal particles, thereby increasing the viscosity and rheology of the coating, and improving the applicability of the paint. Two,increase the adhesion of paint: Due to the high viscosity characteristics of HPMC, it can increase the adhesion of paint, reduce the dripping and flowing of coating, and thus enhance the adhesion of paint. Three, Improve the scratch resistance and water resistance of the coating: HPMC can form a soft film, form a protective layer on the surface of the coating, improve the scratch resistance and water resistance of the coating, and in this way protect the coating from the outside world Scratches and water erosion. Four, adjust the drying speed of the coating: HPMC can absorb excess water molecules in the paint, reduce the drying speed of the paint, make the paint easier to control, and improve the applicability and aesthetics of the coating. Five, increase the stability of the coating: HPMC, as a stabilizer, can effectively prevent the precipitation and stratification of particles in the coating, maintain the uniformity and stability of the coating, thereby improving the quality and service life of the coating. In summary, the role of HPMC in alcohol-based coatings is very important, which can improve the physical and chemical properties of coatings, improve the quality and service life of coatings.