| 摘要 |
NEW MATERIAL:A spiropyran compound expressed by formula I (formula II is substituted or unsubstituted norbornylidene; formula III is substituted or unsubstituted aromatic hydrocarbon group, substituted or unsubstituted unsaturated heterocylcic group; R1 and R2 are H, alkyl, aralkyl, aryl or substituted amino). EXAMPLE:A compound expressed by formula IV. USE:A photochromic material having characteristics of directly coloring by irradiation of ultraviolet ray though assuming a stable colorless state in a normal state with hardly any influence of the kind of matrix in a high polymer matrix and returning to the colorless state at a high fading rate in the order of sec by stopping the irradiation and repeating the discoloration with excellent durability. PREPARATION:A compound expressed by formula V is reacted with a compound expressed by formula VI in the presence of a condensing agent and the resultant compound expressed by formula VII is reduced and further dehydrated to afford the compound expressed by formula I (R1 and R2 are H). |
