In organic photoreceptors with the layered structure, there is the issue of latent image degradation, namely the image blurring caused by lateral motion of photogenerated charge carriers during their transit from the charge generation layer to the surface of the charge transport layer. In this paper, the latent image degradation is investigated mathematically, taking into account the fact that the transportation of charge carrier is described by the drift mobility (μ) and the diffusion coefficient (D). It is concluded that the latent image degradation occurs about 1000 dpi without diffusion process and the degradation increases with the thickness of the charge transport layer. On the other hand, the effect of diffusion process is not negligible for the latent image degradation when D/μ exceeds 10 V. In order to investigate the relationship between the value of D/μ and microscopic properties of transport materials within the framework of Bässler's disorder formalism, the Monte Carlo simulations of the time flight signals are performed for various values of energetic disorder parameter σ and geometrical disorder parameter Σ. It is revealed that D/μ increases when both σ and Σ increase. The disorder parameters are important in discussing the latent image degradation cased by the effect of diffusion process.

View full abstract

Many experimental methods to obtain particle diameter or tribo-electric charge of toner in two-component developer have been investigated. In this study, to make up the simultaneous measurement of individual particle size and electric charge of toner in two-component developer, dual-beam frequency biased laser Doppler velocimeter method was offered introducing a new data processing treatment. As a consequence, particle diameter dependence on electric charge of toner within the range of diameter from 4 μm to 9 μm, was studied using several kinds of pulverized toner specimen with different average values in diameter. From the experimental results the n-th power dependence of diameter on tribo-charge of polyester toner of negative type in contact with ferrite binder carrier in two-component developer is 2.07 or 2.35 when they are coated with or without silica, respectively.

View full abstract