摘要 |
Disclosed are photochromic resins having improved photochromic properties; articles, notably ophthalmic articles, which are constituted, wholly or in part only, of such resins; radically polymerizable compositions which are precursors of said resins; and methods of preparing said resins. Said resins are obtained by radical copolymerization of particular comonomers. They contain an effective amount of at least one acidic additive or of at least one basic additive, and they have improved kinetics of return to the light state. |