SEAL COATING
Seal Coating is the process of applying a coal tar emulsion over an asphalt pavement to protect from the damaging effects of the environment, including moisture and ultraviolet oxidation. Protecting pavement with seal coating has basically the same effect as using sun screen on your skin or varnish on wood because it slows down the destructive effects of the climate. Seal coating also fills minor voids in the surface. Other benefits include creating uniform color and appearance.