PHOTOCHROMIC FLUORENOPYRANS WITH DEFINED DIBENZO[B,D]PYRANO FUSED ATTACHMENT

摘要

The present invention relates to photochromic fluorenopyrans with defined dibenzo[b,d]pyrano fusion in accordance with general formulae (I) or (II) and to their use in plastics of all kinds, particularly for ophthalmic purposes. The photochromic compounds of the invention are distinguished by two pronounced absorption bands of the open form in the visible wavelength range, meaning that with dye molecules of this kind it is possible to replace two conventional photochromic dyes each having only one discrete absorption band. The compounds of the invention, moreover, have a very good lifetime with very high performance.