A photochromic compound having a high color-developing sensitivity, a large fading rate and good durability of photochromic property. A novel chromene compound is, for example, represented by the following formula,
and in which, as a basic structure, a condensed ring having a particular divalent group bonded to carbon atoms at the fourth and fifth positions of a fluoreno group is spiro-bonded to the first position of an indene ring, a particular divalent group is bonded to carbon atoms at the fifth and sixth positions of a chromene ring to form a condensed ring, and particular substituents are bonded to a carbon atom at the second position of the chromene ring.
一种具有高色发展敏感度、大褪色速率和良好光致变色性能耐久性的光致变色化合物。例如,一种新的色烯化合物可由以下公式表示,其中,作为基本结构,将具有特定二价基团与
芴基团的第四和第五位置上的碳原子键合的缩环与
茚环的第一位置螺旋键合,将特定二价基团键合到色烯环的第五和第六位置的碳原子上形成缩环,并将特定取代基键合到色烯环的第二位置的碳原子上。