LIGHT IMAGE FORMATIONS ON DEPROTONATED POLYANILINE FILMS CONTAINING TIO2 PARTICLES

Formation of novel light images of high resolution in polyaniline films containing TiO2 particles is described. The light images are produced by scanning the third harmonic of a Nd:YAG laser on the polyaniline films or by exposing the polyaniline films to lights from a xenon lamp through patterned masks. The keys for the light image formation are (1) to incorporate the semiconductor particles into polyaniline, (2) to convert highly conductive polyaniline into insulating one by utilizing deprotonation which is induced to occur by immersing the conducting polyaniline in aqueous neutral solutions or by anodically polarizing in aliphatic alcohol solutions such as methanol and ethanol solutions, and (3) to use a hole scavenger capable of releasing protons on its oxidation such as above alcohols. The quantum efficiency for the light image formation determined at 355 nm under a low illumination intensity was ca. 10%. The mechanisms of the formation of light images are discussed.