Improvement of Photoinduced Fatigue Phenomenon of Monolayered Organic Photoconductor using Carbazolecarbaldehyde Hydrazone Derivative as Charge Transport Material

Abstract

In this report, improvement of a photoinduced fatigue phenomenon of a monolayered organic photoconductor (OPC) due to the photochemical reaction product of a carbozolecarbaldehyde hydrazone derivative used for charge transport material is discussed. Inhibition of the photochemical reaction with UV light is effective. The addition of UV light absorbent and quencher of the photo-excited state ene rgy of the hydrazone compound into the monolayered OPC were examined. Results show that both UV light absorbent and energy quencher were effective for the improvement of the fatigue and do not lower much the photosensitivity of the monolayered OPC. In our monolayered OPC, ULA and FH (see formulae)are recommended as UV light absorbent and energy quencher, respectively. In the latter case, the amount required is smaller. The large quantity of the addition of UV light absorbent makes the softening point of monolayered OPC film lower. As the OPC film having lower softening point is not desirable, the improvement of photoinduced fatigue by the addition of energy quencher is superior of the improvement by the addition of UV light absorbent.