Cellulose Acetate Phthalate (CAP)

 Cellulose Acetate Phthalate (CAP) is a cellulose derivative obtained by esterification of cellulose with acetic acid and phthalic anhydride. It appears as a white to off-white, free-flowing powder that is insoluble in water but soluble in alkaline solutions and certain organic solvents. CAP is primarily used as an enteric coating agent in pharmaceutical formulations, providing resistance to acidic gastric fluids and enabling targeted release of drugs in the intestines. Due to its film-forming, pH-sensitive solubility, and protective properties, CAP is also applied in food, cosmetics, and specialty industrial uses.