Novel photochromic indeno-fused naphthopyrans

Abstract From the Canadian patent

Described are novel photochromic indeno-fused naphthopyran compounds examples , of which are naphthopyran compounds having a substituted or unsubstituted indeno group, the 2,1 positions of which are fused to the f side of the naphtho portion of the naphthopyran, and having certain substituents at the 3position of the pyran ring. Certain substituents may also be present at the number 5, 6, 7, 8, 9, 10, 11, 12 or 13 carbon atoms of the compounds. These compounds may be represented by graphic formula (I). Also described are polymeric organic host materials that contain or that are coated with such compounds. Optically clear articles such as ophthalmic lenses or other plastic …