A method for preparing a photochromic material is provided. The photochromic material is a spiropyran compound with a nitro group at the 5′ position and a long-chain alkyl group at the 1′ position. Since a nitro group is present in the compound obtained by the present method, the colored form of the compound possesses absorption sensitivity in the wavelength region of a semiconductor laser beam. Moreover, the photochromic reactions of the compound are of high stability. Furthermore, since the compound possess a long-chain substituent at the 1′ position, ultrathin films of extremely high uniformity can be formed from the compound by the Langmuir-Blodgett method.
本发明提供了一种制备光致变色材料的方法。这种光致变色材料是一种螺
吡喃化合物,其 5′位上有一个硝基,1′位上有一个长链烷基。由于本方法得到的化合物中含有硝基,因此该化合物的有色形式在半导体激光束的波长区域内具有吸收敏感性。此外,该化合物的光致变色反应具有很高的稳定性。此外,由于该化合物在 1′位置上具有长链取代基,因此可通过 Langmuir-Blodgett 法由该化合物形成均匀度极高的超薄薄膜。