LENS SUBJECTED TO WATER-REPELLENCY TREATMENT

摘要

PROBLEM TO BE SOLVED: To extend the pot life of a water repellent and to prevent production of shrinkage strain caused by hardening, by treating the lens base body with a specified water repellent to form a water-repelling layer having a specified contact angle. SOLUTION: A lens base body is treated with a water-repellent comprising a compd. [I], [II] or [III] to form a water-repelling layer comprising a non- hardening material and having >80 contact angle (preferably >90). [I] A compsn. comprising an organo-polysiloxane and an acid catalyst and having neither hydroxyl groups nor hydrolytic groups. [II] A monofunctional org. silane compd. having fluorinated org. groups. [III] A silazane compd. expressed by formula [RfR2 Si]2 NH. In the formula, Rf is a fluorinated org. group, R is a univalent hydrocarbon group and two of R may be same or different. The obtd. lens shows no white trace of pads even when someone breathes on the lens. This means the lens is commercially valuable. Moreover, the lens has good appearance without deposition of dust and seems valuable.