Abstract: An electrophotographic photosensitive member having the structure comprising a conductive substrate laminated thereon with (i) a charge generation layer comprising two or more kinds of charge-generating materials incorporated in binder resins and (ii) a charge transport layer, wherein said charge generation layer comprises at least a first charge generating material dispersed in a first binder resin and a second charge generating material dispersed in a second binder resin, such that the binder resins in the charge generating layer are incompatible with each other.

Abstract: A toner composition comprised of electrostatically attractable fusible powder particles, having an average particle size in the range of 1 to 100 .mu.m and a melt viscosity at 190.degree. C. in the range of 20 to 200 Pa.s, said powder particles comprising a coloring substance, a polymeric binder which consists essentially of a copolymer of:(1) styrene or styrene homologue,(2) an alkyl acrylate or alkyl methacrylate monomer wherein alkyl is a straight chain of at least 8 carbon atoms, and(3) a crosslinking monomer containing at least two ethylenically unsaturated groups,the binder copolymer constituting more than 50% of the total weight of the powder particles.

Abstract: An electrophotographic photoreceptor comprising a conductive substrate and a photoconductive layer disposed on the conductive substrate to generate photocarriers upon light radiation. The photoconductive layer comprises a charge-generating layer and a charge-retaining layer. At least part of the charge-generating layer has a plurality of thin microcrystalline semiconductor layers containing silicon as a major constituent and at least one element selected from the group consisting of carbon, hydrogen, and nitrogen. The plurality of microcrystalline layers produce a superlattice structure. The adjacent thin microcrystalline semiconductor layers have different element concentrations. At least part of the charge-retaining layer has a first amorphous semiconductor layer containing silicon as a major constituent and a second amorphous semiconductor layer containing silicon as a major constituent, and at least one element selected from the group consisting of carbon, oxygen, and nitrogen.

Abstract: A dry toner for developing latent electrostatic images in electrostatic copying and printing processes contains, as charge-control substance, a pigment of the formula ##STR1## in which A.sup.- represents a silicomolybdate anion,R.sup.1 and R.sup.3 represent, independently of each other, hydrogen, alkyl or aralkyl,R.sup.2 and R.sup.4 represent, independently of each other, hydrogen, alkyl, aralkyl or aryl, orR.sup.1, R.sup.2, R.sup.3 and R.sup.4 represent, independently of each other, members of a five- or six-membered ring produced by linkage with the o-position of the benzene ring orR.sup.1 and R.sup.2 or R.sup.3 and R.sup.4 jointly represent members of a five- or six-membered ring,B represents oxygen, sulphur or N--R,R represents hydrogen, alkyl or aryl andD represents CH, C--CN or N,in which the two benzene rings may be fused with a further benzene ring and then NR.sup.3 R.sup.

Abstract: A toner for developing electrostatic latent images characterized in that the toner comprises an aluminum compound of a hydroxycarboxylic acid which may be substituted with alkyl and/or aralkyl.

Abstract: An improved reusable multiactive electrophotographic element has a charge-transport layer comprising a triarylamine charge-transport material in a mixture of binders comprising poly[2,2-bis(4-hydroxyphenyl)propane carbonate] and a polyester of 2,2-bis(4-hydroxyphenyl)propane and terephthalic and isophthalic acids, with the weight ratio of the polycarbonate to the polyester being in the range of 9:1 to 3:7.

Abstract: An improved reusable multiactive electrophotographic element has a charge-transport layer comprising a triarylamin charge-transport material in a mixture of binders comprising poly[2,2-bis(4-hydroxyphenyl)propane carbonate] and a polyester of 4,4'-(2-norbornylidene)diphenol and terephthalic and azelaic acids, with the weight ratio of the polycarbonate to the polyester being in the range of 9:1 to 3:7.

Abstract: New electrostatographic developers are provided, containing dual function polymeric binder/charge agents. The new developers contain toner particles comprising a vinyl addition binder polymer containing a quaternary phosphonium salt, wherein the phosphonium salt has an anionic portion covalently bonded to the binder polymer.

Abstract: New electrostatographic toners and developers are provided, containing dual function polyester binder/charge agents. The new toner particle has an average diameter in the range of 0.01 to 100 micrometers and comprises a binder polyester and a charge-control agent comprising a quaternary phosphonium salt, wherein the phosphonium salt has an anionic portion comprising a sulfonate group covalently bonded to a moiety containing at least one ester linkage to the binder polyester.

Abstract: In the photoreceptor described in the specification, an electroconductive base has an amorphous silicon type photoconductive layer coated over a blocking layer on the base and an amorphous carbon-containing surface layer, coated over a buffer layer on the photoconductive layer, has a hardness on the free surface side which is higher than the hardness on the buffer surface side. Apparatus for preparing the photoreceptor includes a CVD vacuum chamber and an arrangement for supplying selected layer-forming gases to the chamber in a controlled manner.

Abstract: New electrostatographic developers are provided, containing dual function polymeric binder/charge agents. The new developers contain toner particles comprising a vinyl addition binder polymer containing a quaternary phosphonium salt, wherein the phosphonium salt has a cationic portion comprising a phosphorus atom covalently bonded to the binder polymer.

Abstract: New electrostatographic toners and developers are provided, containing dual function polyester binder/charge agents. The new toner particle has an average diameter in the range of 0.01 to 100 micrometers and comprises a binder polyester and a charge-control agent comprising a quaternary phosphonium salt, wherein the phosphonium salt has a cationic portion comprising a phosphorus atom covalently bonded to at least one moiety containing an ester linkage to the binder polyester.

Abstract: Suspension stabilizer particles are removed from the surface of polymer particles formed in a limiting coalescence formation technique by dissolving in a solution containing a fluoralkyl polyether surface active agent.

Abstract: Toner and/or carrier particles are prepared by dissolving a polymer in a solvent which is immiscible with water forming a suspension of small droplets of the polymer and solvent in water containing a promoter and silica particles, removing the solvent from the droplets and separating the solidified particles from the water.

Abstract: A triboelectrically chargeable monocomponent toner powder is provided which comprises as a binder a mixture of a copolymer of styrene and an acrylate with an amine-containing aliphatic wax as a charge-control agent. The toner is inherently strongly chargeable positively through triboelectric forces.

Abstract: Method of making electrostatographic multi-color reproductions on plain bond paper receiver sheets in such a manner that the sheets have the high quality look of coated paper while not being subject to the coated paper problems of blistering and differences in gloss level build up. According to the method of this invention, electrostatographically formed color images of information to be reproduced are respectively developed with corresponding colored marking particles, and a negative image of the information to be reproduced is developed with white marking particles. The marking particle developed images are sequentially transferred to a plain bond paper receiver sheet in superimposed register. The transferred images are then fixed to the receiver sheet by application of heat and/or pressure. The white marking particles cover the area of the receiver sheet not covered by the colored marking particles.

Abstract: An electrophotographic photoconductor comprising an electroconductive support, an intermediate layer formed thereon, an a photoconductive layer formed on said intermediate layer, which intermediate layer comprises at least one component selected from the group consisting of: (a) monohydric aliphatic alcohol, (b) dihydric aliphatic alcohol, (c) polyethylene glycol, (d) polypropylene glycol, (e) polybutylene glycol, (f) polyethylene glycol monoester and/or polyethylene glycol diester, (g) polyethylene monoether, (h) crown ether, (i) a random or block copolymer having as structure units a hydroxyethylene group and a hydroxypropylene group, and hydroxyl groups at the terminal thereof, and (j) a polymer of a monomer having formula (I) and a copolymer of said monomer and a counterpart monomer: ##STR1## wherein R.sup.1 represents hydrogen or a methyl group; R.sup.2 represents hydrogen, a lower alkyl group or an unsubstituted or substituted aryl group; and n is an integer of 2 to 100.

Abstract: A persistent conductivity-type electrophotographic recording member comprising a nonconductive layer and a photoconductive layer disposed on one surface of the nonconductive layer, wherein the photoconductive layer comprises a photosensitive material substantially uniformly dispersed in a binder which consists essentially of a copolymer of styrene with at least one alkyl acrylate, the alkyl group of which comprises from four to twelve carbon atoms. The acid value of such copolymers is typically preferably below about 2, and more preferably below about 1.

Abstract: Dry or liquid developers capable of forming high resolution electrostatographic images are made from finely divided toner particles comprising a fusible branched chain, polyester resin which contains 2,3-dihydro,1,3-dioxo-2-yl-1H-isoindole-ar(-yl or -diyl) groups derived, for example, from a 2,3-dihydro-1,3-dioxo-1H-isoindole-5-carboxylic acid. The toner compositions are brittle and can be ground to very small particle size for high resolution image development; they have good cohesivity and resist toner offset; they are fusible at low temperatures; and, in preferred embodiments, are capable of forming transparent color images.

Abstract: Disclosed are single component conductive cold pressure fixable toner compositions with a resistivity of from about 5.times.10.sup.4 to about 10.sup.7 ohm-cm for ionographic development systems and comprised of a blend of resin particles and magnetite particles; and present on the surface thereof pigment particles having absorbed thereon release fluids.