| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a photochromic material having an electron-withdrawing substituent. <P>SOLUTION: The photochromic material includes an indeno-fused naphthopyran having a first electron-withdrawing substituent and, in certain non-limiting embodiments, a second electron-withdrawing substituent. The photochromic materials according to the various embodiments may display faster fade rates, bathochromic shift, and higher performance ratings compared to comparable indeno-fused naphthopyrans without the electron-withdrawing substituents. Photochromic compositions and articles, such as optical elements, incorporating the photochromic materials are also disclosed. <P>COPYRIGHT: (C)2012,JPO&INPIT |
