| abstract |
A chromene compound which has an indeno(2,1-f)naphtho(1,2-b)pyran structure as the basic skeleton and has a substituent comprising an (un)substituted aryl, e.g., methoxyphenyl, or an (un)substituted heteroaryl, e.g., thienyl, bonded to the 7-position carbon atom of the indeno(2,1-f)naphtho(1,2-b)pyran structure. An example of the compound is represented by the following formula (I). This photochromic compound has a medium tone when in a colored state. It has high sensitivity in coloration and a high discoloration rate and has satisfactory photochromic durability. |