Patents by Inventor P. Keith Watson

P. Keith Watson has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6072971
    Abstract: In an electrophotographic printing machine, a layer of insulating fluid containing micelles is positioned over a photoreceptor. The micelles are migrated onto the surface of the photoreceptor. The photoreceptor is exposed to inject charge carriers into the insulating fluid and selectively neutralize micelles to form an electrostatic latent image. The latent image is transferred to a dielectric surface and developed.
    Type: Grant
    Filed: December 21, 1998
    Date of Patent: June 6, 2000
    Assignee: Xerox Corporation
    Inventors: Henry R. Till, P. Keith Watson
  • Patent number: 5754930
    Abstract: An apparatus for developing a latent image recorded on an imaging surface, comprising a housing defining a chamber storing a supply of developer material comprising toner a porous toner donor member spaced from the surface and being adapted to transport toner to a region opposed from the imaging surface; and means for conveying said developer material in the chamber of said housing onto said donor member.
    Type: Grant
    Filed: October 1, 1996
    Date of Patent: May 19, 1998
    Assignee: Xerox Corporation
    Inventors: Howard M. Stark, P. Keith Watson
  • Patent number: 5397673
    Abstract: Disclosed is a process for forming images which comprises applying a curable liquid to a first substrate in an image pattern, optionally transferring the curable liquid image to a second substrate, subsequently contacting the curable liquid image with a solid developer so that the developer adheres to the curable liquid image, optionally transferring the curable liquid and the solid developer in image pattern to a third substrate, and curing the curable liquid in the image pattern to a solid.
    Type: Grant
    Filed: November 5, 1992
    Date of Patent: March 14, 1995
    Assignee: Xerox Corporation
    Inventors: P. Keith Watson, Ian D. Morrison
  • Patent number: 4877698
    Abstract: A process for generating two-color images comprising: (1) charging an imaging member in an imaging apparatus; (2) creating on the member a latent image comprising areas of high, intermediate, and low potential; (3) providing an electrode having a potential within about 100 volts of that of the intermediate potential, enabling generation of an electric field and a developement zone between the imaging member and the electrode; and (4) developing the latent image by introducing into the development zone a liquid developer composition containing first toner particles of one color and second toner particles of another color, the particles being dispersed in a liquid medium, wherein the second toner particles are attached to the high potential and the first toner particles are attracted to the low potential.
    Type: Grant
    Filed: May 23, 1988
    Date of Patent: October 31, 1989
    Assignee: Xerox Corporation
    Inventors: P. Keith Watson, Ian D. Morrison, Melvin D. Croucher
  • Patent number: 4804601
    Abstract: An imaging process which comprises the formation of an image on an imaging member; subsequently developing the aforementioned image with an electrophoretic liquid developer composition comprised of an insulating suspending fluid with a resistivity of from about 10.sup.12 ohm-cm to about 10.sup.16 ohm-cm, pigment particles, a stabilizer component, and a charge control additive; and wherein the resulting ink has a resistivity of from about 10.sup.9 to about 10.sup.12 ohm-cm; applying the ink composition from an applicator roll, which roll transports the ink to the imaging member surface; and wherein the ink is attracted to the charged areas of the imaging member.
    Type: Grant
    Filed: June 29, 1987
    Date of Patent: February 14, 1989
    Assignee: Xerox Corporation
    Inventors: P. Keith Watson, Henry R. Till, Melvin D. Croucher
  • Patent number: 4346985
    Abstract: An automatic development control for use in an electrophotographic apparatus. The control includes a pair of substantially planar members forming a channel therebetween through which developer flows. One of the members is constructed such that an electrostatic charge pattern is periodically formed on the surface thereof, the charge pattern being developed by the attraction of toner thereto which toner has a charge opposite to that forming the charge pattern. The member on which the developed charge pattern is formed includes a uniform, transparent conducting substrate covered with a transparent insulating layer on top of which is deposited a set of spaced-apart, opaque and electrically conducting fingers. Thus, the one member includes alternate opaque and transparent areas.
    Type: Grant
    Filed: June 25, 1979
    Date of Patent: August 31, 1982
    Assignee: Xerox Corporation
    Inventors: P. Keith Watson, Lawrence J. Fraser
  • Patent number: 3980477
    Abstract: An improved photoelectrophoretic imaging method is disclosed wherein a blocking layer is provided with a coating which interacts, in the dark, with the pigment particles of the imaging suspension so as to provide a uniformly charged imaging suspension upon exposure of the suspension to an electric field. The coating material occupies at least a substantially equal position in the Dark Charge Injection Series as any pigment in the imaging suspension. Subsequent or simultaneous electromagnetic radiation to which at least some of the particles are sensitive then results in the formation of optically positive and negative images.
    Type: Grant
    Filed: November 26, 1974
    Date of Patent: September 14, 1976
    Assignee: Xerox Corporation
    Inventors: P. Keith Watson, Paul J. Cressman, Richard V. LaDonna
  • Patent number: 3967960
    Abstract: An improved photoelectrophoretic imaging method is disclosed wherein the imaging suspension is brought into contact under a first electrical field with a blocking layer having a coating which interacts, in the dark, with the pigment particles of the imaging suspension so as to provide a uniformly charged imaging suspension. The imaging suspension is then exposed to appropriate electromagnetic radiation while under a second electrical field. A second blocking layer, free of said coating is employed to produce positive and negative images.
    Type: Grant
    Filed: October 21, 1974
    Date of Patent: July 6, 1976
    Assignee: Xerox Corporation
    Inventors: P. Keith Watson, Paul J. Cressman, Richard V. LaDonna