Benzo-, naphtho- and phenanthrochromene substituted by carbamated or ureated phenyls, preparation thereof and compositions and articles containing them

摘要

Disclosed are novel benzo-, naphtho- and phenanthrochromenes substituted by carbamated or ureated phenyls having the following general formula (I): wherein R₁ represents a group their preparation, photochromic compositions and articles containing them. This family of compounds have interesting and useful photochromic properties, especially in terms of absorption band and discoloration speed.