By Andrew Shooter, Tom Annable and Stuart Richards, Lubrizol Performance Coatings. Paint and ink formulators face significant challenges in producing high-performance coatings in water. Dispersing pigments in water is more challenging than in solvent-based systems as there is a greater potential for self-assembly of the dispersant in the aqueous medium, and this makes adsorption and wetting of the pigment surfaces difficult. Some of the latest water-borne dispersants ...