Hansen Solubility Parameters (HSP) offer a practical way to predict compatibility between the many components in a coating formulation such as polymers, resins, pigments, dispersants, and solvents.

The approach describes materials based on three types of intermolecular interactions: dispersion forces (δD), polar forces (δP), and hydrogen bonding (δH).  The principle is straightforward: when two materials have similar HSP values, they are more likely to be compatible and thermodynamically stable together.

In solventborne coatings, selecting the right solvent, or blend of solvents, is critical for achieving proper solubility, film formation, viscosity, and overall stability.  Yet when a solvent must be replaced due to sustainability, safety, odor, supply, or cost considerations, finding an effective alternative can be difficult and often requires extensive laboratory screening.