| abstract |
Various non-limiting modalities described herein refer to photochromic materials that have extended pi-conjugated systems. For example, various non-limiting modalities described herein provide a photochromic material, such as a fused indefinite naphthopyran, comprising a group that extends the pi-conjugated system of fused indefinite naphthopypyran bonded in a position 11. In addition, the photochromic materials according to Certain non-limiting modalities described herein may exhibit hyperchromic absorption of electromagnetic radiation compared to conventional fortchromic materials and / or may have a closed-spectrum absorption spectrum that travels bactochromically compared to conventional photochromic materials. Other non-limiting modalities refer to photochromic compositions and photochromic articles, such as optical elements, made using described photochromic materials, and the methods for producing them. |