Patents by Inventor Clifford H. Griffiths

Clifford H. Griffiths 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: 5559588
    Abstract: A liquid ink development (LID) reproduction machine for producing a stabilized liquid toner image having clean-background areas. The reproduction machine includes a movable image bearing member having a photoconductive surface, and latent image forming devices for forming a latent image on the photoconductive surface such that the latent image has image areas and background areas. The reproduction machine also includes a development apparatus containing liquid toner developer material for developing the latent image. The liquid toner developer material includes a carrier liquid having a relatively low conductivity for preventing shorting of image conditioning electric fields through a layer of the liquid toner developer material forming the image.
    Type: Grant
    Filed: September 13, 1995
    Date of Patent: September 24, 1996
    Assignee: Xerox Corporation
    Inventors: James R. Larson, Anthony M. Wallace, Clifford H. Griffiths, Dennis A. Abramsohn
  • Patent number: 5514505
    Abstract: Disclosed is a process which comprises (a) providing a migration imaging member comprising (1) a substrate and (2) a softenable layer comprising a softenable material and a photosensitive migration marking material present in the softenable layer as a monolayer of particles situated at or near the surface of the softenable layer spaced from the substrate; (b) uniformly charging the imaging member; (3) imagewise exposing the charged imaging member to activating radiation at a wavelength to which the migration marking material is sensitive; (d) subsequent to step (c), causing the softenable material to soften and enabling a first portion of the migration marking material to migrate through the softenable material toward the substrate in an imagewise pattern while a second portion of the migration marking material remains substantially unmigrated within the softenable layer; and (e) contacting the second portion of the migration marking material with a transparentizing agent which transparentizes migration marki
    Type: Grant
    Filed: May 15, 1995
    Date of Patent: May 7, 1996
    Assignee: Xerox Corporation
    Inventors: William W. Limburg, Joseph Mammino, George Liebermann, Clifford H. Griffiths, Michael M. Shahin, Shadi L. Malhotra, Liqin Chen, Marie-Eve Perron
  • Patent number: 5443785
    Abstract: A seamless substrate is elastically stretched over a hollow cylindrical porous mandrel having a thermal expansion coefficient not greater than the thermal expansion coefficient of the substrate by applying fluid under pressure through the mandrel and relieving the pressure of the fluid so that the substrate relapses to a shape in close contact with the mandrel. A substrate carrier includes a hollow, substantially cylindrical mandrel formed of a porous material, the mandrel having an outer diameter not greater than the inner diameter of the tubular substrate and means for supplying a pressurized fluid to the interior of the mandrel, wherein the porous material is a material having a thermal expansion coefficient not greater than the thermal expansion coefficient of the substrate.
    Type: Grant
    Filed: January 3, 1994
    Date of Patent: August 22, 1995
    Assignee: Xerox Corporation
    Inventors: Henry T. Mastalski, Clifford H. Griffiths
  • Patent number: 5114736
    Abstract: A method and apparatus for electrostatically spray coating substrates with layers of material having uniform thicknesses is provided. A substrate to be coated is electrically grounded and an electrically charged, atomized spray of coating material is directed toward the substrate from a nozzle. The nozzle is traversed along a length of the substrate, which can also be rotated, to coat substantially the entire surface of the substrate. In order to compensate for thickness variations in the applied coating, the speed of traversal of the nozzle is varied. In a preferred embodiment, where photoreceptor drums are produced by spraying a photoreceptor material onto a cylindrical substrate, the speed of traversal of the nozzle is reduced as it approaches at least one end of the cylindrical substrate.
    Type: Grant
    Filed: December 27, 1989
    Date of Patent: May 19, 1992
    Assignee: Xerox Corporation
    Inventors: Clifford H. Griffiths, Paul J. Brach, Edward C. Williams, Ronald A. Gaither, Timothy J. Leenhouts
  • Patent number: 5100628
    Abstract: A method and apparatus for coating photoreceptors used in copying machines. Prior to coating, an elastically deformable material is placed about the external surface of a mandrel to accommodate the belt. The thickness of the material is such that when the belt is pushed over the mandrel the deformable material is deformed and engages the interior surfaces of the belt facing the mandrel. As a result of heating and cooling steps involved during the coating process, the belt contracts and expands differently than the mandrel. The deformable material deforms accordingly to maintain consistent contact throughout between it and the undersurface of the belt.
    Type: Grant
    Filed: December 31, 1990
    Date of Patent: March 31, 1992
    Assignee: Xerox Corporation
    Inventors: Clifford H. Griffiths, Henry T. Mastalski
  • Patent number: 5069758
    Abstract: A layered photosensitive imaging member is modified to reduce the effects of interference within the member caused by reflections from coherent light incident on a base ground plane. The modification described is to form the ground plane surface with a rough surface morphology by an electroforming process which leaves the surface with a matte-like finish. Light reflected from the ground plane formed with the matte finish is diffused through the bulk of the photosensitive layer breaking up the interference fringe patterns which are otherwise later manifested as a plywood pattern on output prints made from the exposed sensitive medium.
    Type: Grant
    Filed: January 28, 1991
    Date of Patent: December 3, 1991
    Assignee: Xerox Corporation
    Inventors: William G. Herbert, John R. Andrews, Clifford H. Griffiths
  • Patent number: 4747992
    Abstract: A process is disclosed for forming at least one thin substantially uniform fluid coating comprising polymeric film forming material on a cylindrical mandrel, solidifying the fluid coating to form a uniform solid coating and separating the uniform solid coating from the mandrel. The process may comprise forming at least one thin substantially uniform fluid coating comprising polymeric film forming material around a cylindrical mandrel, the mandrel having a larger mass or lower thermal conductivity than the polymeric film forming material and a critical surface tension greater than the surface tension of the fluid coating, solidifying the fluid coating to form at least one thin substantially uniform solid coating comprising the polymeric film forming material around the cylindrical mandrel, heating both the uniform solid coating and the mandrel to a temperature at least above the apparent T.sub.
    Type: Grant
    Filed: March 24, 1986
    Date of Patent: May 31, 1988
    Inventors: Donald S. Sypula, Merlin E. Scharfe, Dennis A. Abramsohn, Paul J. Brach, Clifford H. Griffiths, Deborah J. Nichol-Landry, Andrew R. Melnyk, John W. Spiewak, Joseph Mammino, Edward C. Williams, Lieng-Huang Lee, Christine J. Tarnawskyj
  • Patent number: 4410616
    Abstract: This invention is directed to an improved ambipolar photoresponsive device useful in imaging systems for the production of positive images, from either positive or negative originals, which device is comprised of:(a) supporting substrate,(b) a first photogenerating layer,(c) a charge transport layer, and(d) a second photogenerating layer,wherein the charge transport layer is comprised of a highly insulating organic resin having dissolved therein small molecules of an electrically active material of the formula: ##STR1## wherein X is selected from the group consisting of alkyl and hal
    Type: Grant
    Filed: May 10, 1982
    Date of Patent: October 18, 1983
    Assignee: Xerox Corporation
    Inventors: Clifford H. Griffiths, Andrew R. Melnyk
  • Patent number: 4098795
    Abstract: A method for the preparation of X-form metal-free phthalocyanine and X-form metal-free compounds which comprises heating any metal-free phthalocyanine polymorph or compound to from about 540.degree. to about 580.degree. C and cooling the resulting product formed thereby is herein disclosed.
    Type: Grant
    Filed: November 22, 1972
    Date of Patent: July 4, 1978
    Assignee: Xerox Corporation
    Inventors: Clifford H. Griffiths, Richard C. Keezer
  • Patent number: 4031109
    Abstract: A method for the preparation of X-form metal phthalocyanine and X-form metal-free compounds which comprises heating any suitable metal phthalocyanine polymorph or compound to from about 600.degree. to about 650.degree. and cooling the resulting product formed thereby is herein disclosed.
    Type: Grant
    Filed: November 22, 1972
    Date of Patent: June 21, 1977
    Assignee: Xerox Corporation
    Inventors: Clifford H. Griffiths, Richard C. Keezer
  • Patent number: 3932180
    Abstract: Process for direct alpha to X phase conversion of metal-free phthalocyanine. In this process, the alpha polymorph of a metal-free phthalocyanine pigment can be directly converted to the X form by depositing the alpha form of the pigment on a suitable substrate followed by in situ conversion of this deposit by controlled heating. The X form of metal-free phthalocyanine is known to possess good electrophotographic speed, and, thus, can be used either alone or in combination with other photoconductive materials in electrophotography.
    Type: Grant
    Filed: June 4, 1973
    Date of Patent: January 13, 1976
    Assignee: Xerox Corporation
    Inventors: Clifford H. Griffiths, Michael S. Walker