Polymeric binders having saturated ring for improved performance of single layer positive organic photoconductor

摘要

Composites comprising polymeric binders and phthalocyanine pigments to form a single layer positive organic photoconductor are provided for use in electrophotography. The polymeric binders comprise an aliphatic polymer or copolymer having a saturated ring for each repeat unit either included in the polymer chain or pendant therefrom and about 4 to 35% of functional groups such as --OH, --SH, --N , NH, and --NH.sub.2 per repeat unit. The saturated ring portion, being essentially non-polar, or at least less polar than an unsaturated ring, maintains the specific morphology of the phthalo-cyanine pigments commonly employed in positive charge organic photoconductors (OPCs) and results in a stable dispersion required for the stable performance of the OPC. Keeping the functional groups listed above to less than about 35% ensures that the photoresponse is not reduced to an unacceptable level. Heating of the composite is used to control the concentration of the functional groups. One or more separate thermal carrier generation control agents comprising compounds containing the functional group(s) may be used to provide part or all of the functional groups in the composite. The resulting composite evidences thermal stability of electronic properties, such as dark decay, at elevated temperatures in the range of about 35° to 75° C.