Abstract: An electrographic, two-component dry developer composition including charged toner particles and oppositely charged carrier particles which (a) includes: an combination of a soft magnetic material exhibiting a coercivity of at least 300 gauss when magnetically saturated, exhibit an induced magnetic moment of less than 20 EMU/gm of carrier when in an applied field of 1000 gauss and (b) a hard magnetic material exhibiting a coercivity of at least 300 gauss when magnetically saturated, exhibit an induced magnetic moment of at least 20 EMU/gm of carrier when in an applied field of 1000 gauss.

Abstract: In a development system there is provided 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; a plurality of trim bars positioned about the donor roll at a predefined positions and spacing around the donor roll, the a plurality of trim bars progressively reducing developer bed height of the developer material on the donor member to a predefine developer bed height within the development nip.

Abstract: A development system is provided that extends the functionality of liquid developer to produce custom colors and combines it with a powder development engine to enable custom color printing. This invention provides a apparatus and method, control scheme, hardware, and software, necessary for enabling custom color printing using an electrophotograpic hybrid technology.

Abstract: A toner maintenance system for an electrophotographic developer unit, including a sump for storing a quantity of developer material comprised of carrier and toner material; a first member for transporting a mixture of developer material and toner particles from the sump, the first member having a voltage applied thereto; a metering blade, positioned closely adjacent to the first member to maintain the compressed pile height of the developer material on first member at a desired level; and a sensor device for measuring the current between the first member and the metering blade, and generating a signal indicative thereof.

Abstract: A development system is provided that extends the functionality of liquid developer to produce custom colors and combines it with a powder development engine to enable custom color printing. This invention provides a apparatus and method, control scheme, hardware, and software, necessary for enabling custom color printing using an electrophotograpic hybrid technology.

Abstract: An apparatus for developing a latent image recorded on an imaging surface, including a housing defining a reservoir storing a supply of developer material including toner. A donor member is spaced from the imaging surface, for transporting toner on an outer surface of the donor member to a region opposed from the imaging surface. A mag roll loads toner onto a region of the outer surface of the donor member. A charging device ion charges the toner loaded on the region of the donor member. An AC/DC voltage supply for biasing the donor member positioned in close proximity to the imaging member to detach toner from the donor member as to form a toner cloud for developing the latent image. A second charging device discharges and removes residual toner on the region of the donor and returning the toner to the reservoir.

Abstract: A wheelable backpack having a front portion to carry items therein, a rear portion to rest against the back of a person using the backpack in a back-carrying mode and a pair of shoulder straps to enable the person to use the backpack in the back-carrying mode, a pair of channels substantially parallel to and spaced with respect to each other disposed in a rear portion extending from the top to the bottom of the backpack; a handle device disposed in the pair of channels; a pair of compartments disposed in the bottom portion with each of the pair of compartments being disposed in communication with a different one of the pair of channels; a pair of wheels each disposed in a different one of the pair of compartments; and a mechanical arrangement disposed in each of the pair of channels connected between the handle device and each of the pair of wheels to convert linear motion of the handle means to rotary motion to extend each of the pair of wheels out of their associated one of the pair of compartments when the

Abstract: A system for removing residual contaminants from an image conditioning apparatus that removes excess liquid from a developed image made up of toner particles immersed in a liquid carrier medium on an image bearing member. The system includes a vacuum blotting device that contacts the liquid developed image and absorbs a portion of the liquid carrier and residual contaminants remain thereon. A contact member adapted to be shifted from a non-operative position spaced from the vacuum blotting device, to an operative position in contact with the vacuum blotting device operates to transfer the contaminants therefrom. A scraper removes the transferred contaminants from the contact member. The contact member is pivotally mounted about the pivot point to effect shifting of the contact member between the non-operative and the operative position.

Abstract: A system for removing excess carrier liquid from an electrostatic image developed with liquid developing material made up of toner particles immersed in a liquid carrier medium on an image bearing member. The system includes an absorbent contact roller for absorbing at least a portion of the liquid carrier off of the liquid image, and vacuum source coupled to the contact roller for generating both negative pressure at the surface of the roller to draw the absorbed liquid through the contact roller, and positive air pressure for pushing contaminated liquid out of the roller.

Abstract: A method and apparatus for eliminating undesirable development of background charge potentials in a multicolor electrostatographic system is disclosed, wherein the application of a developer bias at a given development station is selectively controlled to be substantially equal to or greater than the background image voltage of the image generated by a preceding imaging station such that the voltage differential between toner particles at the development station and the background areas including the previous image areas is substantially zero and the electrostatic forces acting on the toner particles are insufficient to attract the toner particles to the residual image.

Abstract: An image protecting conditioning roll for conditioning developed images in a liquid immersion development reproduction machine. The image protecting conditioning roll includes a rigid, conductive and porous core; an absorbent intermediate layer formed over the rigid core; and an inelastic image protecting top, outer layer formed over the absorbent intermediate layer, for contacting and protecting an image being conditioned, by preventing undesirable image offset and image smearing.

Abstract: An apparatus for developing an electrostatic latent image with liquid developing material. The apparatus includes a liquid developing material coating flow applicator for applying a substantially uniform coating of liquid developing material to a moving surface, wherein a housing, situated proximate to the moving surface, includes a fluid transport channel having a relatively narrow-width elongated outlet port for delivering a flow of liquid developing material to the moving surface, and an air flow channel having an elongated inlet aperture located adjacent the moving surface and immediately upstream from said outlet port for applying vacuum pressure to the flow of liquid developing material for varying the profile of the coating flow to provide variation of flow stability as well as thickness. A discussion of the effects of variations in the outlet port geometry, in particular, increasing the dimension between the downstream wall and the surface to be coated, has also been provided.

Abstract: A high differential air pressure assisted blotting device for conditioning, on an image bearing member, liquid developer images consisting of charged toner particles and carrier liquid. The high differential air pressure blotting device includes a movable porous blotter belt forming an endless loop and having an outer surface for contacting and blotting carrier liquid from an image being conditioned, and a backup roller positioned at a first location within the endless loop for contacting a first portion of the blotter belt to gently urge the blotter belt into blotting-contact with the image being conditioned.

Abstract: A method and apparatus for filtering and sensing a developer fluid in a printing or copying machine for processing purposes. In order to insure that developer fluid reclaimed from a developing process is free from contamination, a filter/sensor system is provided in the reclaimed fluid path. The reclaimed fluid passes through the filter and then the sensor senses the amount of toner remaining in the fluid. If the toner contamination level is too high, the fluid is recirculated to the filter where it is re-filtered. This process is repeated until the reclaimed fluid is free of contaminants. The filter/sensor system can also indicate process failure in the developing system. Cleaning a developer housing is yet another use for the recirculating sensor/filter process. In this mode the developer fluid in the toner sump is circulated through the sensor/filter until all of toner has been removed from the fluid.

Abstract: A method and apparatus for simultaneously developing and transferring a liquid toner image. The method includes the steps of moving a photoreceptor including a charge bearing surface having a first electrical potential, applying a uniform layer of charge having a second electrical potential onto the charge bearing surface, and imagewise dissipating charge from selected portions on the charge bearing surface to form a latent image electrostatically, such that the charge-dissipated portions of the charge bearing surface have the first electrical potential of the charge bearing surface. The method also includes the steps of moving an intermediate transfer member biased to a third electrical potential that lies between said first and said second potentials, into a nip forming relationship with the moving imaging member to form a process nip.

Abstract: A process for the preparation of liquid developers with reduced fines which comprises heating a liquid developer comprised of thermoplastic resin, pigment, charge adjuvant, liquid hydrocarbon, and optional charge director, wherein said heating is accomplished at about 5.degree. C. below the melting point of said thermoplastic resin, which heating enables said fines comprised of said developer components, and of a size diameter of from about 0.1 to about 0.4 micron to be reduced.

Abstract: In accordance with the present invention, there is provided in a liquid electrophotographic reproduction machine, a development unit for developing latent images on an image bearing member using liquid developer material. The development unit includes a housing defining a liquid developer material holding chamber, and a quantity of liquid developer material contained within the chamber. The quantity of developer material includes carrier liquid and charged toner particles dispersed within the quantity of carrier liquid. The development unit also includes a heating element located inside the quantity of developer material for heating the quantity of developer material. The quantity of developer material when heated has a desired elevated temperature within a range of 50 to 60 degrees centigrade for improved developability without causing toner particle agglomeration.

Abstract: An apparatus for developing an electrostatic latent image with liquid developing material. The apparatus includes a liquid developing material applicator, wherein a single piece housing fabricated from a non-conductive material is provided for defining an elongated aperture adapted for transporting liquid developing material into contact with the image on the surface of a photoreceptive member, the housing further including a planar surface adjacent the elongated aperture for providing a liquid developing material application region in which the liquid developing material can flow freely in contact with the photoreceptive member. A developing roll situated adjacent to and downstream from the liquid developing material is also provided for for attracting the liquid developing material to image areas of the electrostatic latent image.

Abstract: An apparatus develops an electrostatic latent image on a charge-retentive surface. A donor roll is selectably rotatable in a process direction and in a reverse direction relative to the process direction. A toner mover loads toner particles onto a portion of the surface of the donor roll. A metering blade is disposed downstream of the toner mover in the process direction. A seal is disposed upstream of the toner mover in the process direction, and is adapted to remove at least approximately half of the undeveloped toner from the donor roll.

Abstract: A roller for controlling the application of carrier liquid to an image bearing member in an electrostatographic reproduction apparatus having a rigid porous electroconductive supportive core, a conformable microporous covering provided around the core, and a pressure controller. The pressure controller is located to provide a positive or negative pressure within the porous core and across a cross section of the core and covering.