Abstract: A toner binder comprising a crosslinked polyester resin obtained by using 0.1 to 3 mol % of trimellitic acid and 0.1 to 5 mol % of an epi-bis type epoxy in combination as crosslinking components, said binder having a number average molecular weight (Mn) in the chromatogram determined by a gel permeation chromatography on the non-gel portion of the polyester resin, of 2,000 to 4,000, a ratio (Mw/Mn) of the weight average molecular weight to the number average molecular weight of 10 to 25 and a (percent gel) of the residue unsoluble in tetrahydrofuran solvent of 1 wt % or less. A toner composition for flash fixing comprising the above-described binder as an essential constituent component. The toner and the toner binder exhibit good fixability and void resistance upon flash fixing and produce little fixing odor.

Abstract: A toner binder is disclosed which comprises a polyester resin in which an aliphatic hydrocarbon chain terminated with an ester and/or an ether bond to the aliphatic group contains a constituent element consisting of ethylene in an amount of from 1 to 5 wt % based on the total weight of the resin. Further disclosed is a toner binder using both of a crosslinked polyester having a peak molecular weight of 10,000 or less and a linear polyester having a peak molecular weight of 8,000 or more as binder resins, the peak molecular weight of the linear polyester being greater than the peak molecular weight of the crosslinked polyester.

Abstract: A developing device using a one-component developer composed of toner particles, which includes a vessel for holding the developer, and a developing roller rotatably provided within the vessel so that a portion of the roller is exposed therefrom and faces a surface of an electrostatic latent image carrying body to form a developing area. During rotation of the roller, the toner particles are entrained by a surface of the roller to form a developer layer therearound, and are carried to the developing area for a development of an electrostatic latent image formed on the latent image carrying body. The roller and the latent image carrying body are reversely rotated such that the surfaces thereof move upward at the developing area. A blade member is provided within the vessel and is resiliently engaged with the roller for regulating a thickness of the developer layer, and is disposed below the roller to prevent a leakage of the toner particles from the vessel at an underside of the developing roller.

Abstract: A system including a plurality of processing units wherein one power source is connected to the plurality of processing units, is constituted such that when a total of maximum rated currents of the processing units exceeds an allowable current of the power source, an allowance or nonallowance of the power supplied to the processing units is determined from a state of the power source and the power supply is controlled thereby, and whereby the power source does not become overloaded. Thus, the system avoids overloading the power source if a sum of the maximum rated currents of respective connected processing units exceeds the allowable current of a power source.

Abstract: An electrophotographic recording apparatus includes a photoconductive drum having a toner image developed on a surface of the drum, a transfer station having a transfer unit located above the photoconductive drum to transfer the toner image onto an underside surface of a paper moving along a predetermined path extending between the photoconductive drum and the transfer unit. The paper will be fed toward the transfer station in an upward orientation by feed rollers. Also, a fixing unit is provided along the path and downstream of a point of separation of the paper from the photoconductive drum, to fix the toner image onto the paper with the recorded surface facing down when the paper is ejected from the transfer station, and a guide for smoothly guiding the leading end of the paper into an entrance of the fixing unit.

Abstract: An electrophotographic recording apparatus comprising a rotatable photosensitive drum and unit for electrifying the drum, depositing an electrostatic latent image on the drum, developing the latent image, transferring the image on the drum to printing paper, and optical-deelectrifying the drum. In this method, the optical deelectrification unit is located at a position opposite to the drum with respect to a passage of the printing paper, and an optical deelectrification beam is irradiated to the drum only when the printing paper interrupts an optical path of the deelectrification light toward the drum.