Patent attributes
A photochromic compound is provided, which may be a pyran, an oxazine, or a fulgide. The photochromic compound has at least one substituent Q attached thereto, each Q independently being —N3, —CN, —COOR′, —CCR′, —C(R′)C(R′)R′, —OCOR′, —OCOOR′, —SR′, —OSO2R′″, and/or —CON(R′)R′, wherein each R′ is hydrogen, an unsubstituted or substituted alkyl group having from 1 to 18 carbon atoms; an unsubstituted or substituted aryl group, an unsubstituted or substituted alkene or alkyne group having from 2 to 18 carbon atoms, wherein the substituents are halo or hydroxyl and R″′ is —CF3 or a perfluorinated alkyl group having from 2 to 18 carbon atoms The number, locations and nature of the constituents Q are dependent upon the structure of the photochromic compound.