Abstract: A toner powder for the development of latent electrostatic or magnetic images, the toner powder containing a polyester resin based on an etherified diphenol and a dicarboxylic acid mixed with a reaction product of an epoxy resin and a phenol compound or a carboxylic acid, and the process for forming fixed images on an image receiving material utilizing the above toner powder, the surface of an intermediate medium consisting of material having a lower affinity for the softened toner powder than does the image receiving material and the toner powder being softened by heating before and/or during transit through a pressure zone.

Abstract: Encapsulated electrostatographic toner particles and a process for making toner particles. The toner particles comprise a pressure fixable core encapsulated in a pressure rupturable shell with the outer surface of the shell being hydrophobic. Preferably, the outer surface of the shell is rendered hydrophobic by having a thermosetting resin precipitated thereon. The process for producing electrostatographic toner particles comprises preparing a core material, encapsulating a discrete portion of the core material in a shell by interfacial polycondensation, and then treating the outer surfaces of the shells with a thermosetting resin to render them hydrophobic. This enables the particles to be formed as a free-flowing, dry powder without requiring costly spray drying.

Abstract: A laminate film suitable for providing a transparency for an OHP (overhead projector) is formed by disposing an absorbing layer on a substrate. The absorbing layer functions to allow addition of a wax component to a toner so as to improve the color mixing characteristic and anti-offset characteristic of the toner without causing a wax exudation trace which is liable to occur in a fixed toner image if the absorbing layer is not provided.

Abstract: Disclosed is a toner composition for electrophotography which comprises, as a principal component, a urethane-modified polyester resin whose loss tangent (tan .delta.) has a maximum and a minimum both falling within the range of from 0.7 to 2.5, the loss tangent being determined at 150.degree. C. and a frequency ranging from 10.sup.-2 to 10 Hz. The toner composition has excellent low temperature fixing ability and offset resistance as well as a wide range of permitted fixing temperature.

Abstract: There is disclosed an electrophotographic photosensitive member having a photosensitive layer containing a disazo pigment represented by the following general formula (1) or (2); ##STR1## The photosensitive member has excellent durability and high sensitivity.

Abstract: A color image forming method by superimposing plural kinds of toner with different colors on a surface of a photoreceptor body is disclosed. The surface of the photoreceptor is uniformly pre-charged with electricity. A kind of toner is selected according to a predetermined order. A latent image corresponding to the selected toner, and consequently corresponding to a selected color, is formed on the surface by a photo-electric exposure. A toner image is formed by developing the latent image with the selected toner. A multiple color image is formed by repeating the above two steps with regard to succeeding colors and kinds of toners until all kinds of toner having been developed. In repeating the development, the following formulas are satisfied under the supposition that (Q/M)n is an amount of electrification of toner used in the n-th development.1.1=<(Q/M)n/(Q/M)n+1=<1.51.

Abstract: In an electrophotographic toner, by using as the binder resin a styrene/acrylic resin in which in the gel permeation chromatogram, a high molecular weight peak value appears in a molecular weight region higher than 1.times.10.sup.5, a low molecular weight peak value appears in a molecular weight region of from 2.times.10.sup.4 to 500, a minimum value appears halfways between the two peaks and the ratio (V/P) of the area of the valley to the peak area is lower than 0.3, the internal cohesive force of the binder resin for the toner can be prominently improved while maintaining the low-temperature fixing property and offset resistance at high levels, and pulverization of the toner and formation of the spent toner can be prevented during the developing operation and the durability of the toner can be improved.

Abstract: An electrophotographic photosensitive member comprises an electroconductive support and a photosensitive layer formed thereon. The photosensitive layer contains a compound represented by the general formula: ##STR1## The compound provide an electrophotographic photosensitive member which has excellent sensitivity and potential stability.

Abstract: An apparatus for obtaining carrier particles which comprises in operative relationship a container means, a rotating means, a moving transporting means in contact with the container means and the rotating means, and a magnet means attached to the transporting means.

Abstract: The improved toner is produced by supplying a spheroidizing treatment under mechanical impact force to resin particles that contain at least magnetic particles in a resin and said magnetic particles are substantially spherical in shape.

Abstract: An electrophotographic photosensitive member has a conductive substrate and a photosensitive layer formed thereon. The photosensitive layer contains a compound represented by the following formula (1): ##STR1## wherein R.sub.1 and R.sub.2 are the same or different and are each a hydrogen atom, a halogen atom, substituted or unsubstituted alkyl group, and substituted or unsubstituted aryl group, m and n are each of 0. 1 or 2, and A.sub.1 and A.sub.2 are the same or different and are each a coupler residue having a phenolic hydroxyl group.

Abstract: A microcapsule toner is produced through the steps of: passing resinous base particles (A1) comprising at least a binder resin and modifier particles (B) having a particle size ratio of 0.2 or less with respect to the base particles (A1) through an impact zone having a minimum clearance of 0.5-5 mm between a rotating member and a fixed member or between at least two rotating members at an ambient temperature of 10.degree.-90.degree. C. thereby to fix the modifier particles (B) onto the surfaces of the base particles (A1) under the action of a mechanical impact force to form particles (A2), the modifier particles (B) being particles selected from the group consisting of charge-controlling particles releasing particles, colored particles, charge-suppressing particles and abrasive particles; and passing the particles (A2) and shell-forming resin particles (C) having a particle size ratio of 0.2 or less with respect to the particles (A2) through an impact zone having a minimum clearance of 0.

Abstract: A process for avoiding, or minimizing toner contamination of electrodes in a scavengeless electrophotographic imaging apparatus which comprises adding to the donor roll present in said apparatus a toner comprised of resin, pigment, charge additive, and a metal oxide, or a mixture of metal oxides.

Abstract: An electrophotographic dry developer which comprises a carrier and toner particles comprising a binder resin comprising (A) a polyester resin and (B) a styrene-acrylic resin obtained by co-polymerizing a monomer having an amino group, at a weight ratio of (A) to (B) ranging from 55:45 to 95:5, both resin (A) and resin (B) and a dyestuff or pigment of chromatic color. It is positively charageable and serves for color electrophotography.

Abstract: A negatively chargeable toner for developing latent electrostatic images comprising a binder resin, a coloring agent and a charge controlling agent which comprises a fluorine-containing quaternary ammonium salt of formula (I): ##STR1## wherein X represents --SO.sub.2 or --CO; R.sub.1, R.sub.2, R.sub.3 and R.sub.4 independently represent hydrogen, an alkyl group having 1 to 10 carbon atoms or an aryl group; m is an integer of 1 to 5; and n is an integer of 1 to 10.

Abstract: An electrophotographic photoreceptor of laminate-type comprises in sequence a conductive substrate, a carrier transport layer and carrier generation layer, both of an organic substance, and a surface protective layer. The surface protective layer exhibits greatly improved humidity resistance and comprises either a fluorine-containing acrylic graft copolymer or a urethane resin such that the layer has a pure water contact angle of at least 70 degrees.

Abstract: A color toner, comprises non-magnetic resin particles containing a coloring agent and two types of inorganic oxide particles, wherein;particles of coloring agent have an average particle diameter D of 300 m.mu..ltoreq.D.ltoreq.800 m.mu. as determined by measurement of scattered-light intensity; coloring agent particles with a particle diameter of from (D-120) m.mu. to (D+120) m.mu. account for not less than 90% of the whole; coloring agent particles with a particle diameter of 169 m.mu. or less account for not more than 1.0%; and coloring agent particles with a particle diameter of 949 m.mu. or more account for not more than 0.5%;said color toner has a volume average diameter of from 6 to 10 .mu.m; colored resin particles with a particle diameter of 5 .mu.m or less are contained in a proportion of from 15 to 40% by number; colored resin particles with a particle diameter of from 12.7 to 16.0 .mu.m are contained in an amount of from 0.1 to 5.

Abstract: An electrophotoreceptor comprising a conductive substrate, a charge generation layer and a charge transport layer wherein the charge transport layer comprises a polymeric binder and a charge transport material. The improvement resides in that a copolymer of styrene and maleic acid is used as the binder in the charge transport material. The photoreceptor exhibits improved sensitivity, residual potential, durability and reproducibility.

Abstract: A toner composition comprised of resin particles, pigment particles, and a quaternary ammonium hydrogen bisulfate charge enhancing additive.

Abstract: A toner composition comprised of pigment particles and a branched polyalkyl/styrene/butadiene copolymer of the following formula ##STR1## wherein m, n and o are weight fraction numbers, p represents the number of CH.sub.2 groups, R is hydrogen or alkyl, and R' is carbonyloxy or aryl.