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AssigneeHewlett-Packard Company
InventorsKhe C. Nguyen, Sivapackia Ganapathiappan
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An inverse dual-layer organic photoconductor comprising a charge generation layer (CGL) formed on top of a charge transport layer (CTL), in turn formed on a substrate such as a web (drum) or subbing layer, is disclosed, in which the CGL includes a flexible polymer having a glass transition temperature (T.sub.g) of less than about 120.degree. C. as the binder for a charge generation species and in which the CTL includes a rigid polymer having a T.sub.g of greater than about 120.degree. C. as the binder for a charge transport species. The CTL is coated onto the substrate, using a non-chlorinated solvent. The CGL is coated onto the CTL, also using a non-chlorinated solvent, under conditions so as to form a diffused region at the boundary of the CGL and CTL. This type of photoconductor yields extremely low noise, exceptionally high-speed and excellent stable charging/discharging performance in the xerography process at room temperature and elevated temperature.
A reverse dual-layer organic photoconductor comprising a charge generation layer formed on top of a charge transport layer formed on top of a substrate, said charge generation layer comprising at least one charge generation molecular species selected from the group consisting of dyes and pigments and first binder molecules in a first composite matrix and said charge transport layer comprising at least one hole transport molecular species and second binder molecules in a second composite matrix, said first binder in said charge generation layer comprising at least one comparatively flexible, thermoplastic or thermoset polymer having a glass transition temperature of less than about 120.degree. C. in its thermoplastic state and said second binder in said charge transport layer comprising a polymer having at least one cycloalkyl group to provide said polymer with a glass transition temperature of greater than about 120.degree. C., said charge generation layer and said charge transport layer separated by a clear diffused region comprising penetration of said first binder into said second binder, said clear diffused region having a thickness ranging from about 1 to 20% of that of said charge transport layer and providing said reverse dual-layer organic photoconductor with improved performance compared to reverse dual-layer organic photoconductors having no diffused region or a hazy diffused region.
Dependencies are inferred from the claim text.