TRAPPING LAYER OVERCOATED INORGANIC PHOTORESPONSIVE DEVICE

摘要

This invention is generally directed to inorganic overcoated photoresponsive devices comprised of a substrate, a layer of hole injecting material capable of injecting holes into a layer on its surface, this layer being comprised of trigonal selenium, a hole transport layer in operative contact with the hole injecting layer, this layer being comprised of a halogen doped seleniumarsenic alloy, wherein the percentage by weight of selenium present is from about 99.5 percent to about 99.9 percent, the percentage by weight of arsenic present is from about 9.1 percent to about 0.5 percent, and the halogen is present in an amount of from about 10 parts per million, to about 200 parts per million; a charge generating layer overcoated on the hole transport layer, comprised of an inorganic photoconductive material; a hole trapping layer overcoated on the generator layer, the trapping layer being comprised of a halogen doped selenium arsenic alloy, containing from about 95 percent selenium, to 99.9 percent selenium, from about 0.1 percent to about 5 percent of arsenic and 10 parts per million to 200 parts per million of a halogen material, and a layer of insulating organic resin overlaying the charge generating layer. This device is useful in an electrophotographic imaging system using in a preferred embodiment a double charging sequence, that is, negative charging, following by positive charging.