Chapter 20: Paint Industries

The paint and coating application areas comprise (1) architectural coatings or house paints, which includes waterborne latex, exterior and interior solvent-borne paints, lacquers, and wood and furniture finishes; (2) industrial coatings including automotive, metal, machinery, and equipment finishes, paper coatings, electric insulating varnishes, and magnetic wire coatings; (3) special purpose coatings like industrial maintenance paints, marine coatings, traffic and metallic paints, automobile refinishing coatings, aerosol paints, and multicolor paints; and (4) miscellaneous products like paints used for graphics and artwork. A typical paint and coatings manufacturing operation involves formulation, milling, or grinding of pigments, mixing, filtering, filling, and equipment cleaning. The production process for a liquid paint starts with the dispersion of pigments, solvents, resins, and additives in a mill such as ball or bead mill, or a high-speed disperser. Diluents, resins, bactericides, fungicides, etc., are added to the dispersion mill effluent in a process known as letdown. When the formulation achieves the desired properties, mixing is stopped, the paint is filtered, and the final product is stored in cans for shipment. Paint manufacture requires several hundred raw materials, which include antifoams, defoamers, dispersants, surfactants, driers, antiskinning agents, extenders, fillers, pigments, flame or fire retardants, flatting agents, latex emulsions, oils, preservatives, bactericides, fungicides, resins, rheological and viscosity control agents, silicone additives, titanium dioxides, and colors.