| The disazo compounds have high sensitivity, low dark decay, excellent photoelectrical stability, wide spectral range and low cost. They were widely used as charge generation materials (CGM) in organic photoconductors (OPC). The disazo compounds containing benzoxazole moiety, that have also high stability, good water resistance, and wonderful durability, were studied in this paper.Firstly, 2-(4'-amidophenyl)-6-amidobenzoxazole was prepared through the reduction of 2-(4'-nitrophenyl)-6-nitrobenzoxazole using Fe power as reductant. The effects of the dosage of hydrochloric acid and reaction time on the reaction were investigated. The optimal technical conditions was: n(2-(4'-nitrophenyl)-6-nitrobenz-oxazole):n(hydrochloric acid):n(Fe) = 1:9:6, reaction 8 hours under 95~100℃. The purity and yield of obtained product was 98.6% and 59.2% respectively. Three disazocompounds were synthesized through diazotization and coupling reaction with 2-(4'-amidophenyl)-6-amidobenzoxazole as disazo component, and naphthol and its analogues as the coupling component. The yields of the three compounds were 76.5%, 61.4% and 65.2%. The structures and purities of the synthesized compounds were confirmed by IR, UV and HPLC. The synthesized disazo compounds were sensitized by Soxhlet extraction.The technical conditions, such as solvents and circumfluence time were studied. The sample, which was Soxhlet extracted with chloromethane as solvent and circumfusing time of 180, had most excellent photoconductivity.The relationship between applied charatersitics of OPC and its preparation conditions was studied. The idealing photoconductivity was obtained when using tetrahydrofuran as dispersant of CGM and mills time of 2 hours. The appearance of charge generation layer (CGL) was measured by particle size distribution NG and AFM. The results showed that, the particle size of CGM was smaller than 0.4μm, and the height of CGL surface is lower than 800nm.
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