Scratch resistant coatings provide lenses with durability and increased longevity. A high quality thermally cured dip hardcoat provides the best scratch resistance and provides for the most durable ingredient for an AR coating application. Plastic lens materials scratch easily than glass materials, and therefore benefit greatly with application of a durable hardcoat.
Two of the more common types of hard coats are:
Thermally cured dip hard coating
The lens is slowly passed through a liquid bath of a solvent based hardcoat where the coating solution adheres to both convex and concave sides of the lens. The hardcoat is then allowed to cure in a high temperature chamber until stable.
U.V. cured hard coating
A liquid hardcoat solution is applied to the concave side of the lens using a spinning process. Lenses are then cured under a UV (Ultra Violet) light for a specific amount of time.