Elektrophotographisches Element

摘要

1350278 Electro-photographic element MATSUSHITA ELECTRIC INDUSTRIAL CO Ltd 30 Sept 1971 [7 Oct 1970 8 Oct 1970 (3) 13 Oct 1970] 45602/71 Heading G2C An electro-photographic element comprises a conductive support, a photo-conductive layer comprising at least one of poly-N-vinyl carbazole, poly N- alkenyl carbazole, or a nuclearsubstituted poly -N-vinyl carbazole and a layer 0À1 to 1 Á thick of at least one of these polymers and an organic sensitizer, the photo-conductive layer and the sensitizer-containing layer being 3 to 30 Á thick. The sensitizer may be a pyrylium, thiapyrylium, carbonium or benzopyrylium salt or the reaction product of a benzopyrylium salt with a pyrane. The photo-conductive layer is formed by coating the support with an organic solvent solution of the poly carbazole optionally containing a plasticizer e.g. chlorinated diphenyl or an epoxy resin and a resin e.g. a polycarbonate. After the photo-conductive layer has dried its top surface is coated with a solution of the sensitizer or a leuco base thereof using a solvent which will partially dissolve the photoconductive layer. Alternatively the sensitizer may be vacuum deposited and the deposited surface exposed to solvent vapour. The solution of sensitizer may contain a plasticizer, a polycarbonate and a monomer corresponding to the polymer of the photo-conductive layer. The sensitivity of the element can be enhanced by heating.