Electron transport layer over an inorganic photoconductive layer

Claim 1

A method of imaging which comprises: a. providing a xerographic plate having a supporting substrate, an unoriented inorganic photoconductive layer overlaying said substrate, and an electronically active transport layer overlaying said photoconductive layer, said photoconductive layer comprising a photoconductor having the capability of photogenerating electrons and injecting them into an adjacent active transport layer, said active layer having the capability of supporting the injection of electrons and transporting said electrons through said active material wherein said active material comprises at least one material selected from the group consisting of phthalic anhydride, tetrachlorophthalic anhydride, benzil, mellitic anhydride, s-tricyanobenzene, picryl chloride, 2,4-dinitrochlorobenzene, 2,4-dinitrobromobenzene, 4-nitrobiphenyl, 4,4-dinitrobiphenyl, 2,4, 6-trinitroanisole, trichlorotrinitrobenzene, trinitro-o-toluene 4,6-dichloro-1,3-dinitrobenzene, 4,6-dibromo-1,3-dinitrobenzene, p-dinitrobenzene, chloranil, bromanil, 2,4,7-trinitro-9-fluorenone, 2,4,5,7-tetranitrofluorenone, trinitroanthracene, dinitroacridine, tetracyanopyrene, and dinitroanthraquinone; the photoconductive layer having a thickness between 0.02 and 25 microns and dispersed in from 0 to 95 volume percent binder but comprising at least 25 volume percent when an electronically inert binder is employed, the photoconductor binder thickness ranging from 0.05 to 20 microns when a binder is employed; the transport material, if dispersed in an electronically inert binder, is present in a volume ratio of at least 25 percent active transport material to electronically inert biNder; b. uniformly positive charging said plate, and c. exposing said plate to a source of radiation in the wavelength region of from about 4200 to 6500 Angstroms to which the active layer is substantially transparent and non-absorbing whereby injection and transport of photogenerated electrons from said photoconductive layer occurs through said active transport layer to form a latent electrostatic image on the surface of said plate.

Claim 2

A method of imaging which comprises: a. providing a xerographic plate having a supporting substrate, an unoriented inorganic photoconductive layer overlaying said substrate, and an electronically active transport layer overlaying said photoconductive layer, said photoconductive layer comprising a photoconductor having the capability of photogenerating electrons and injecting them into an adjacent active transport layer, said active layer having the capability of supporting the injection of electrons and transporting said electrons through said active material wherein said active material comprises at least one material selected from the group consisting of phthalic anhydride, tetrachlorophthalic anhydride, benzil, mellitic anhydride, s-tricyanobenzene, picryl chloride, 2,4-dinitrochlorobenzene, 2,4-dinitrobromobenzene, 4-nitrobiphenyl, 4,4-dinitrobiphenyl, 2,4, 6-trinitroanisole, trichlorotrinitrobenzene, trinitro-o-toluene 4,6-dichloro-1,3-dinitrobenzene, 4,6-dibromo-1,3-dinitrobenzene, p-dinitrobenzene, chloranil, bromanil, 2,4,7-trinitro-9-fluorenone, 2,4,5,7-tetranitrofluorenone, trinitroanthracene, dinitroacridine, tetracyanopyrene, and dinitroanthraquinone; the photoconductive layer having a thickness between 0.02 and 25 microns and dispersed in from 0 to 95 volume percent binder but comprising at least 25 volume percent when an electronically inert binder is employed, the photoconductor binder thickness ranging from 0.05 to 20 microns when a binder is employed; the transport material, if dispersed in an electronically inert binder, is present in a volume ratio of at least 25 percent active transport material to electronically inert biNder; b. uniformly positive charging said plate, and c. exposing said plate to a source of radiation in the wavelength region of from about 4200 to 6500 Angstroms to which the active layer is substantially transparent and non-absorbing whereby injection and transport of photogenerated electrons from said photoconductive layer occurs through said active transport layer to form a latent electrostatic image on the surface of said plate.