Examples of the binder resin suitably used for the charge transport layer may include: insulating resins, such as acrylic resin, polyarylate, polyester, polycarbonate, polystyrene, acrylonitrile-styrene copolymer, polyacrylamide, polyamide and chlorinated rubber; and organic photoconductive polymers, such as poly-N-vinylcarbazole and polyvinylanthracene.