Used primarily as a light stabilizer in polymers, especially in polyolefins, polyurethanes, and polyesters. It protects materials from degradation caused by UV radiation, helping to prevent discoloration, cracking, and loss of mechanical strength. Commonly added to agricultural films, packaging films, and outdoor textiles to extend service life. Also effective in coatings and adhesives where long-term weatherability is required. Works synergistically with antioxidants and other UV absorbers to enhance overall stability.