Dr. Dmitri Kopeliovich
High-solids paints are the paints containing at least 65% of solid components (binders, pigments and additives) mixed with a solvent serving as a vehicle.
Due to low content of solvent the viscosity of high-solids paints is 3-4 times higher than in conventional Solvent-borne paints and may reach 10000 cP (centipoise).
The viscosity of high-solids paints may be reduced chemical modification or heating the paint before application to 104-150°F (40-66°C).
High-solids paints are formulated as either a single-component or two-component systems:
Polymer resins used as the binders in high-solids paints:
High-solids paints are applied by spray guns.
High pressure pumps are used in the spray equipment for application of high viscosity high-solids paints.
The paint viscosity may be reduced by a heater mounted between the pump and the spray gun. Two-head spray guns may be used for application of two-component high-solids paints. Two-head spray equipment provides mixing the components in atomized state. The resin and the hardener (cross-linking agent) are supplied from different containers by individual pumps preventing clogging the system due to possible early thickening of the paint.
Advantages of high-solids paints as compared to conventional solvent-borne paints:
Disadvantages of high-solids paints as compared to conventional solvent-borne paints: