Abstract: In a development system including a developer transport adapted for depositing developer material on an imaging surface having an electrostatic latent image thereon, including: a housing defining a chamber storing a supply of developer material including carrier and toner; a donor member, mounted partially in the chamber and spaced from the imaging surface, for transporting developer on an outer surface thereof to a region opposed from the imaging surface the donor member having a magnetic assembly having a plurality of poles, a sleeve, enclosing the magnetic assembly, rotating about the magnetic assembly; the magnetic assembly generating a developer bed having a predefined developer bed height; a grid, interposed between the donor roll and the imaging surface within the predefined bed height, the grid having apertures for permitting carrier and toner therethrough; and means for biasing a region between the grid and the imaging surface at a voltage potential so that toner is ejecting towards the imaging surfa

Abstract: The present invention is concerned with an instant-on fuser having a cylindrical, relatively thin metal cylinder supporting a resistance heating foil or printed circuit secured on the inside surface of the cylinder by a high temperature adhesive. The interior of the cylindrical tube is filled with air. The heating foil or printed circuit is carried on a fiber glass substrate and the heating elements is connected to electrical leads extending through caps on the ends of the cylindrical support. The relatively low thickness, low mass fuser and high temperature materials permit a relatively fast instant-on fuser.

Abstract: An electrophotographic printing machine in which a developer roller transports a developer material comprising carrier granules and toner particles closely adjacent to an electrostatic latent image recorded on a photoconductive surface so as to develop the latent image with the toner particles. A member is positioned closely adjacent to the developer roller to attract the toner particles to at least one surface thereof. A beam of energy is transmitted through the member onto the surface on which the toner particles adhere. The internal angle of incidence of the beam of energy is greater than the critical angle of incidence of the member. The intensity of the beam of energy internally reflected through the member is detected. A signal indicative of the quantity of toner particles attracted to the surface of the member is generated. The signal is processed and a signal transmitted indicating the end of the useful life of the developer material.

Abstract: A printing machine having an operator removable housing comprising a photoconductive member with a web entrained about a portion thereof. A latent image is recorded on the photoconductive member and marking particles transported to the portion of the web entrained about the photoconductive member. In this way, the latent image recorded on the photoconductive member attracts the marking particles to the web in image configuration. A copy sheet is advanced into contact with the marking particles on the web. The marking particles interposed between the web and the copy sheet are heated. After cooling, the copy sheet is separated from the web with the marking particles remaining affixed thereto.

Abstract: This invention relates to a process for rapidly charging uncharged toner particles to a positive polarity, which comprises adding uncharged toner particles to a positively charged developer composition comprising carrier particles and toner particles, the charged and uncharged toner particles containing conductive particles or conductive patches on their surface, which conductive patches are of a higher positive triboelectric charge than the toner polymer, contacting the charged toner particles with the uncharged toner particles causing positive charges to be transferred from the conductive particles on the charged toner particles, to conductive particles on the uncharged toner particles, within a period of from about 5 seconds to about 2 minutes, thereby resulting in substantially the same level of positive charge intensity for both the original charged toner particles and the added toner particles, such charge intensity ranging from about 5 microcoulombs per gram to about 50 microcoulombs per gram.

Abstract: This invention is generally directed to an improved process for rapidly charging uncharged replenishment toner particles to a positive polarity, and the use of such particles for developing images in an electrostatographic imaging system, which process comprises (1) adding uncharged replenishment toner particles to a charged developer composition comprised of carrier particles and toner particles, the carrier particles consisting of a core containing a polymer coating thereon having incorporated therein an additive having a pKa of less than 5, said additive being selected from the group consisting of perfluorooctanoic acid, 2,4-dinitrophenol, 2,4,6-trinitrophenol, and naphthalene sulfonic acids, (2) contacting the charged developing composition containing said carrier particles with the uncharged toner particles, wherein positive charges are transferred to the uncharged toner particles within a mixing period of from about 5 seconds to about 5 minutes, thereby resulting in substantially the same level of posit

Abstract: An apparatus in which the distribution of tones particles is measured as a function of the size and charge thereof. The toner particles pass through a uniform electrical field in the interior chamber of the housing. The resultant deflection from a reference is a function of the size and charge of the particle. A computer driven image analysis system displays a toner charge distribution.

Abstract: This invention is directed to positively charged toners comprised of a resin, a colorant, and an additive possessing an anion, and more specifically, an alkyl pyridinium compound and its corresponding hydrate, of the formulas ##STR1## wherein A is an anion, which in a preferred embodiment is selected from halides such as fluoride, chloride, bromide, or iodide; sulfate, sulfonate, nitrate borate, and phosphate; R is a hydrocarbon radical containing from about 8 to about 22 carbon atoms and preferably from 12 to 18 carbon atoms. An important embodiment of the present invention is directed to a process for rapidly charging (or admixing) uncharged dry electrostatographic toner, containing the alkyl pyridinium compounds of the above formulas, subsequent to its addition to previously charged developer, whereby the uncharged toner particles acquire a charge within a period of from about 1 minute to about 5 minutes.