Organic Photoconductors Using a Novel Charge-Transport Material, 2-[p-Di(p-tolyl)aminostyryl]-4-methylthiazole

Organic photoconductors using 2-[p-di(p-tolyl)aminostyryl]-4-methylthiazole, which is a newly developed material with high hole mobility, as a charge-transport material and (tau)-type metal-free phthalocyanine as a charge-generation material, have been examined. The photoconductors showed an excellent photoresponse, but had a high residual potential. In order to ascertain the reason for this, the variation of the xerographic gain with the thickness of the charge-transport layer and the electric field was measured. The results suggested that a large energy barrier between 2-[p-di(p-tolyl)aminostyryl]-4-methylthiazole and (tau)-type metal-free phthalocyanine induced a large decrease in the xerographic gain at a low electric field, which caused a high residual potential.