Additol P 891 Carboxylated polyester matrix Cytec Surface Specialties North America South and Central America Flow / Levelling agent Powder coating Additol™ P 891 is a flow promoter masterbatch suitable for use in clear powder coatings. Additol™ P 891 contains approximately 5% active substance in an outdoor resistant carboxylated polyester matrix. The addition of about 7-10% on binder is suggested for the manufacture of haze-free clear coatings with very good flow. Flow promoter masterbatch. Shows haze-free clear coatings with very good flow. Used in clear powder coatings.