Photochromic benzodioxine fused naphthopyran compounds, compositions and articles containing those naphthopyran compounds

摘要

Benzodioxino-naphtho[1,2-b]pyran compounds having particularly advantageous photochromic properties, such as, high sensitivity/coloration, two distinct absorption bands in the 430-500 nm range and 520-620 nm range of the visible spectrum may be generally described as a naphthopyran having a central nucleus of the formula: chemistry chemdraw filechemistry mol file;wherein F is a 1,4-benzodioxine ring chemistry chemdraw filechemistry mol file; with its 2,3 positions fused to the i, j, or k faces; and ;R₁ and R₂ are the atoms or groups providing photochromic properties to the naphthopyran