Description : | This nanotechnology based process has been developed for making thermally curable sols (lacquers) for applying optically clear antiscratch coatings on plastic (CR-39®, PC, PMMA etc.) ophthalmic lenses, sheets and other shapes by dip-coating technique. The coatings can be cured at 90-95°C. Main advantages of the coatings are: Higher shelf life (> 30 days at room temperature and >100 days in refrigerator (5±1°C) in closed condition); refractive index of the coatings can be varied from 1.48 1.54; and coating can be done on complicated shapes (e.g. bifocal D- or Oshaped lenses) & previously tinted plastic ophthalmic lenses |