PURPOSE: To stabilize electrophotographic characteristics including residual potential and sensitivity when a photosensitive body is repeatedly used by incorporating a specific disazo pigment into an electric charge generating layer and incorporating a specific arom. polycarboxylic acid into an electric charge transfer layer.
CONSTITUTION: The charge transfer layer is formed on a conductive base by depositing the disazo pigment expressed by the formula [I] by evaporation on the base or coating a coating liquid prepd. by dissolving said pigment into a suitable solvent or, if necessary, by dispersing said pigment into a soln. dissolved with a binder resin on the base and drying the coating. The soln prepd. by dissolving the arom. polycarboxylic acid expressed by the formula [II] and binder and, if necessary, an electric charge transfer material into a suitable solvent is coated thereon and is dried to form the charge transfer layer, by which a lamination type photosensitive body is obtd. The amt. of the arom. polycarboxylic acid to be added varies with the kind thereof and the effect of the addition is higher with the slighter amt. as the number of the carboxyl group contained in the arom. polycarboxylic acid is larger. Said acid needs be added at the higher ratio as the number of the carboxyl group contained therein is smaller.
NISHIYAMA TAKESHI
SAWASHITA YOSHIAKI
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