Thinners are volatile chemical liquids that are a mixture of various solvents. Thinners are commonly employed to dilute paints to smooth painting tools, give the paint better adhesion to the surface, and wash and eliminate grease and contaminants from surfaces.

Thinners can also be very effective in improving paint properties. Adopting the right thinner can play a key role in brushability, sprayability, drying speed of the paint layer, and many other properties of the paint.