The plastisol must be atomized and forced or attracted to the surface of the parts to be coated. In this paper we'll cover conventional air spray, airless spray and electrostatic spray. All spray methods require special formulating and viscosity control. Often thixotropy (viscosity decreases with agitation) must be controlled, especially when applying thicker coatings. Often viscosity must be reduced by the addition of solvents to the compounds. We will sometimes use the term "organosol". This term is used to denote a plastisol that contains 10% or more of solvent.
Surface coatings of a few thousandths of an inch up to fifty thousandths and more in a single pass are possible. They may range in hardness and other physical properties. Coatings must be fused. Ordinarily, merely raising the temperature of the coating and adjacent surfaces up to 350°F completes the process. Organosols with low plasticizer and high solvent levels may require a zoned oven to prevent blistering or mud cracking. Blistering can occur if remaining solvent is forced out after the coating is too well fused.