Abstract: Described are contact lenses having photochromic materials within the central or pupillary area of the lens and methods for manufacturing such lenses. In one method, a photochromic amount of at least one photochromic material is added to the pupillary region of a casting mold containing a polymerizable monomer that can be at least partially cured before and/or after the addition. Another method involves providing an amount of polymerizable photochromic monomer for the pupillary region and an amount of polymerizable non-photochromic monomer for the remainder of the contact lens in a casting mold. The photochromic and non-photochromic monomers can differ by their degree of polymerization, viscosity and/or density.

Abstract: Described are imbibition compositions that incorporate kinetic enhancing additive(s) into photochromic polymeric host material. Kinetic enhancing additives include organic polyol(s), epoxy-containing compound(s) or a mixture thereof that improves the performance of organic photochromic compounds in the polymeric host as determined in the Photochromic Performance Test. Also described is a process for incorporating kinetic enhancing additives into polymeric substrates prior to, after and/or with organic photochromic compounds and the resulting photochromic articles produced by such a process.

Abstract: Described are novel reversible photochromic naphthopyran compounds, examples of which are compounds having a cycloalkyl ester substituent at the number 5 carbon atom and optionally certain substituents at the number 6 carbon atom of the naphtho portion of the naphthopyran and certain substituents at the 2-position of the pyran ring. Substituents may also be present at the number 7, 8, 9 or 10 carbon atoms of the naphtho portion of the naphthopyran. These compounds may be represented by the following graphic formulae: Also described are various substrates, e.g., paper, glass, organic polymeric materials, etc., that contain or that are coated with such compounds. Optically clear articles such as ophthalmic lenses or other plastic transparencies that incorporate the novel naphthopyran compounds or combinations thereof with complementary photochromic compounds, e.g., certain other naphthopyrans, indenonaphthopyrans, benzopyrans, oxazine-type compounds, etc., are also described.