Phosphate Ester Metal Pigment Dispersant MPD-50

Aluminum flake pigments have a reactive surface that generates hydrogen gas when in contact with water or acidic media (2Al + 6H2O → 2Al(OH)3 + 3H2). Phosphate ester dispersants chemisorb onto the aluminum surface, forming a protective layer that suppresses gas evolution and prevents leafing (uncontrolled orientation). They also control the orientation of flakes in the film for optimal metallic effect (flop ratio). Standard anionic polyacrylate dispersants can activate aluminum corrosion rather than protecting it.