Studying of Photochromic Compounds Based on Substituted Indolinospiropyrans

摘要

We synthesized and studied a range of different mono- and di-substituted photochromic materials those were obtained by interaction of salicylic aldehyde and the Fischer base within corresponding derivatives in different solvents. It was shown that photochromic films easily stain under UV and solar light irradiation. The exposure time is over several dozens of seconds at UV-light intensity of 0.1W/cm~2. The relaxation time varies from dozens of seconds to several days, and reduces with temperature increasing. Photochromic materials, based on 6',8'-dinitroindolynospyrobenzpyrans, have a permanent intense color due to the great concentration of merocyanine form, which can not be restored back to the ,,closed" spiropyran form under the usual intensities of laser light. Because there is a bleaching effect of these compounds under exposure of visible light, ones could record images without preliminary UV irradiation.