Abstract: Of developing agents each having a binder containing a polyester resin having an acidic value, wax having a softening point higher than that of the binder, and wax having a softening point lower than that of the binder, the acidic value of a black developing agent is made higher than that of a color developing agent.

Abstract: A developing agent comprising color toners and a cyan toner, the color toners including a yellow toner, a magenta toner, and a black toner, wherein the black toner comprises a binder resin containing a crystalline polyester resin, and the yellow toner, the magenta toner and the cyan toner each comprise a binder resin containing no crystalline polyester resin.

Abstract: A developing agent comprising a binder resin containing a crystalline resin having a crystallinity of 10 to 50%, and the temperature at the DSC heat absorption peak of the developing agent in the heating step differs from the temperature at the DSC heat generation peak of the developing agent in the cooling step.

Abstract: Disclosed is a developing agent using a binder resin including a styrene-acrylic-series resin, a crystalline polyester resin, a first wax having a melting point higher than the softening point of the crystalline polyester resin, and a second wax having a melting point lower than the softening point of the crystalline polyester resin.

Abstract: A binder resin contains a polyester resin, a crystalline polyester resin, a wax having a DSC heat absorption peak temperature not higher than that of the crystalline polyester resin, and another wax having a DSC heat absorption peak temperature higher than that of the crystalline polyester resin.

Abstract: A binder resin includes a first polyester resin having a high softening point Sp1, a second polyester resin having a softening point Sp2 higher than the softening point Sp1, a first wax having a melting point Mp1 higher than the softening point Sp2, and a second wax having a melting point Mp2 lower than the softening point Sp2.

Abstract: Disclosed is toner using coloring agent-containing particles including a particulate coloring agent and a particulate additive treated with mechanochemical processing.

Abstract: Toner comprises rutile/anatase mixed crystal titanium oxide that is externally added to toner particles containing binder resin and coloring agents and hydrophobic processed, and hydrophobic silica externally added to the toner particles.

Abstract: An erasable image forming material includes a color former, a developer, a binder resin, and a polymer decolorizer having an electron donating group capable of physically or chemically adsorbing the developer. This polymer decolorizer is, e.g., a polymer compound having a sugar skeleton, representatively starch. This image forming material can form sharp images and erase images by heat or a solvent to achieve a good erased state.

Abstract: A developing agent exhibiting satisfactory negative charging characteristics can be obtained by allowing the developing agent to contain a toner, which contains a predetermined 2:1 type metal complex salt dye as a charge control agent or as a coloring agent, and carrier particles represented by general formula (MO).sub.X (Fe.sub.2 O.sub.3).sub.Y, obtained by using a kneaded mixture containing predetermined 2:1 type metal complex salt compound particles and a binder resin to have an average particle diameter of 0.2 .mu.m or less, or by allowing a binder resin to contain in advance a low molecular weight wax in manufacturing a developing agent containing a predetermined 2:1 type metal complex salt compound.

Abstract: A substantially chromium-free toner composition which comprises, as a negative charge control agent, one or more complexes of Formula 1: ##STR1## including other acceptable forms of such complex, in which: X+ is H+, Na+ or mixtures thereof; M is Fe or Co; R.sup.1 is sulphonyl or sulphamoyl, substituted by one or more C.sub.1-4 alkyl; and R.sup.2 is carboxy or phenylcarbamoyl, optionally substituted by one or more C.sub.1-4 alkyl; but when R.sub.1 is methylsulphonyl, R.sup.2 is not carboxy.

Abstract: A toner comprises a first particle having a predetermined volume average diameter and including thermoplastic binding resin and a colorant mixed into the thermoplastic binding resin to apply a color thereto. Wax of a second particle whose volume average diameter is considerably smaller than that of the first particle, is attached to the first particle by mechanical pressure. A nonmagnetic particle of a third particle is attached to the wax. The volume average diameter of the third particle is considerably smaller than that of the second particle. The attachment of the nonmagnetic particle decreases the area of an exposed surface of the wax, thereby preventing the wax from being attached to other wax and preventing the wax from contacting another toner.

Abstract: On the surface of a developing roller disposed closely to a photosensitive drum, a toner supplied from a toner container to the surface is spread into a thin layer by a toner distribution and charging blade. The triboelectric charge, q.sub.1, of the toner and the triboelectric charge, q.sub.2, of the surface of the toner distribution and charging blade are equalized in polarity and made to satisfy a relation, .vertline.q.sub.2 .vertline.<.vertline.q.sub.1 .vertline.. The triboelectric charge, q.sub.3, of the surface of the developing roller is made to satisfy a relation, -4.0.ltoreq.q.sub.1 /q.sub.3 .ltoreq.-1.2. The triboelectric charge of the toner, q.sub.1, and the triboelectric charge, q.sub.4, of the surface of a recovery blade for recovering the residue of toner adhering to the developing roller are equalized in polarity and, at the same time, made to satisfy a relation, .vertline.q.sub.4 .vertline.<.vertline.q.sub.1 .vertline..

Abstract: In a first embodiment of the present invention, a plurality of electrode portions are contactably and approachably disposed on an electrostatic latent image holding member in order to equalize a toner image of an electrostatic latent image holding member. In a second embodiment, an elastic foaming apparatus is contactably or approachably disposed to the electrostatic latent image holding member in order to equalize the residual toner distribution on the electrostatic latent image holding member. In a third embodiment, an equalization member consisting of an electric conductor or a resistor is contactably and approachably disposed on the electrostatic latent image holding member in order to equalize the distribution of toner of the transfer residual toner image. An AC electric field may be generated between the equalization member and the electrostatic latent image holding member.

Abstract: A transfer device for transferring a toner image on an image carrier onto a transfer material, including a transfer drum, a supporting device for the transfer material in place on the surface of the transfer drum and an electrode for applying a bias voltage to an electroconductive layer of the transfer drum. The transfer drum includes a rotatably supported drum member, a flexible elastomer layer on the peripheral surface of the drum member, and an electroconductive layer on the elastomer layer. The elastomer layer of the transfer drum is made of a foaming elastomer such as a polyurethane foam so that the transfer material is in contact with the toner image on the image carrier under a small amount of pressure and with an ample contact width.

Abstract: A developing device effects desirable development when the amount of charging of toner, q (C/g), the amount of toner deposited on the surface of a developing roller per unit area, m (g/cm.sup.2), the speed of movement of the surface of the developing roller, v (cm/sec), the available length of the developing roller, l (cm), and the magnitude of electric resistance between the surface of the developing roller and a power source for developing bias, R (.OMEGA.), are adjusted so as to satisfy the formula, .vertline.q.vertline.m.ltoreq.100/vlR. The developing device produces a developed image desirable in quality and free from background fogging when the magnitude of a developing electric current, I (A), is adjusted so as to satisfy the formula, R.ltoreq.200/I.