Xerographic discharge

A variation of the experimental methods described above is the xerographic discharge technique which is gaining wide acceptance in the study of polymeric systems. The polymer film deposited on a metallic substrate is corona charged and... 

Xerographic discharge, which is a highly space-charge-perturbed process, is therefore characterized by significant dispersion in the arrival times of photoinjected carriers. In some cases, the transit times of the slowest carriers are 10 times or more than the transit times of the fast carriers. However, the slowest carriers, too, must exit the TL before the photoreceptor reaches the development zone, typically 0.3-1.0 s after exposure. In practice, carrier mobilities that significantly exceed 10 cm /V-s are desirable. 

Figure 23. Photogeneration quantum yield for H2Pc-based photoreeeptors with 33 wt.% hydrazone (DEH) CTM, as a function of applied field. Open-circle data were obtained by xerographic discharge and filled-circle data from photoacoustic measurements. (Reprinted with permission from Ref [36y].)...

The monomer /8-A -carbazolylethyl vinyl ether is known to copolymerize with MA or N-substituted maleimides in the presence of free-radical initiators.Copolymerizations were run in benzene for 24 h at 60 C, producing low-molecular-weight MA copolymer in an 80% yield and maleimide copolymer in 27-84% yields. Color, due to CTC formation, was observed on mixing the monomer solutions however, spontaneous copolymerization was not observed. Charge-transport properties of the copolymers were measured and discussed, using xerographic discharge techniques. 

Fundamental parameters in photoconductivity studies of solids are the quantum efficiency of photogeneration 0, the injection efficiency Y (where applicable) and the carrier mobility ju. These parameters are not directly obtainable from steady-state measurements, where 0 and appear as products in the expression for photoconductivity. Independent experiments are therefore required [92]. Transient techniques such as time-of-flight (TOF) and xerographic discharge are best suited. Both... 

The photogeneration model in polymer photoconductors based on the geminate recombination theory of Onsager has been used successfully in many cases to describe the experimental data obtained by the xerographic discharge technique. 

Response of photoconductors on step input 2.33.3.4.2.(i)(a) Xerographic discharge Figure 11 illustrates the experimental arrangement. All the experimental units are placed in the light proof and electrically shielded chamber. Measurement in the SPD method consists of three main steps ... 

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