摘要 |
The present invention relates to photochromic double-indeno-fused naphthopyrans of the general formula (I) and the use thereof in plastics of all kinds, particularly for ophthalmic purposes. The photochromic compounds according to the invention are characterized by two distinct absorption bands of the open form in the visible wavelength range, i.e. two conventional photochromic dyes, each having only one discrete absorption band, can be replaced with dye molecules of this type. The compounds according to the invention, moreover, have a very good lifetime with a very high performance. |