| abstract |
The various non-limiting embodiments disclosed herein generally relate to photochromic compounds, which may be thermoreversible or non-thermoreversible, and articles made from the compounds. Other non-limiting embodiments relate to photochromic-dichroic compounds, which may be thermoreversible or non-thermoreversible, and articles made from the compounds. For example, one non-limiting embodiment provides a thermally reversible, photochromic compound adapted to have at least a first state and a second state, wherein the thermally reversible photochromic compound has in at least one state a The average absorption ratio of greater than 2.3. Another non-limiting embodiment provides a photochromic compound comprising: (a) at least one photochromic group selected from pyran, oxazine and fulgid anhydride; and (b) attached to the at least one on a photochromic group and composed of ‑[S 1 ] c ‑[Q 1 ‑[S 2 ] d ] d' ‑[Q 2 ‑[S 3 ] e ] e' ‑[Q 3 ‑ [S 4 ] f ] f' ‑S 5 ‑P at least one extender L. |