Patents by Inventor Charles G. Allen

Charles G. Allen 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).

  • Symmetrical perylene dimers
    Patent number: 5645965
    Abstract: Photoconductive imaging members comprised of a symmetrical dimeric perylene as a charge generator, wherein said perylene is of the following formulawherein R is hydrogen, alkyl, cycloalkyl, oxaalkyl, substituted alkyl, aryl, substituted aryl, aralkyl or substituted aralkyl, and X is the symmetrical bridging moiety, N--N, alkylene, when n is zero, substituted alkylene, cycloalkylene, arylene, substituted arylene, aralkylene, or substituted aralkylene.
    Type: Grant
    Filed: August 8, 1996
    Date of Patent: July 8, 1997
    Assignee: Xerox Corporation
    Inventors: James M. Duff, Charles G. Allen, Ah-Mee Hor, Gordon K. Hamer
  • Hydroxygallium phthalocyanine pigments with block copolymer binders
    Patent number: 5521043
    Abstract: A photoconditive imaging member comprised of a supporting substrate, a photogenerating layer comprised of a photogenerating pigment, or photogenerating pigments dispersed in a polystyrene/poly(methacrylic acid) (A.sub.n -B.sub.m) block copolymer wherein A is the anchoring block, B is the steric stabilizing block, and n and m represent the number of segments; and a charge transport layer.
    Type: Grant
    Filed: May 5, 1995
    Date of Patent: May 28, 1996
    Assignee: Xerox Corporation
    Inventors: Nancy A. Listigovers, Charles G. Allen, Trevor I. Martin, Gordon K. Hamer, Cheng-Kuo Hsiao, Giuseppa Baranyi
  • Benzimidazole perylene imaging members and processes thereof
    Patent number: 5484674
    Abstract: A process which comprises contacting the cis and trans isomers of benzimidazole perylene with cyclohexane.
    Type: Grant
    Filed: October 31, 1994
    Date of Patent: January 16, 1996
    Assignee: Xerox Corporation
    Inventors: Ah-Mee Hor, Charles G. Allen, Paul J. Gerroir
  • Metal phthalocyanines and processes for the preparation thereof
    Patent number: 5405954
    Abstract: Disclosed is a process for the preparation of chloroindium phthalocyanine which comprises heating a mixture of indium trichloride and ortho-phthalodinitrile in a mixture of solvents comprised of a dialkylaminoalkanol and a high boiling second solvent; and cooling the mixture to enable precipitation.
    Type: Grant
    Filed: June 18, 1993
    Date of Patent: April 11, 1995
    Assignee: Xerox Corporation
    Inventors: George Liebermann, Roger E. Gaynor, Ah-Mee Hor, Charles G. Allen
  • Imaging members with mixed binders
    Patent number: 5322755
    Abstract: A layered photoconductive imaging member comprised of a supporting substrate, a photogenerator layer comprised of perylene photoconductive pigments dispersed in a resin binder mixture comprised of at least two polymers, and a charge transport layer.
    Type: Grant
    Filed: January 25, 1993
    Date of Patent: June 21, 1994
    Assignee: Xerox Corporation
    Inventors: Charles G. Allen, Ah-Mee Hor
  • Photoconductive imaging members with polycarbonate binders
    Patent number: 5227449
    Abstract: Block copolymers of the formula ##STR1## wherein R.sub.1, R.sub.2, and R.sub.3 are independently selected from the group consisting of hydrogen, alkyl and aryl; k, j, m and n represent the number of repeating segments, and imaging members thereof.
    Type: Grant
    Filed: October 11, 1991
    Date of Patent: July 13, 1993
    Assignee: Xerox Corporation
    Inventors: Peter G. Odell, Dasarao K. Murti, Charles G. Allen
  • Processes for the preparation of photogenerating pigments
    Patent number: 5153094
    Abstract: A process which comprises adding a pigment to a solution of trihaloacetic acid and toluene; adding the solution to a nonsolvent for the pigment; and separating the product from the solution.
    Type: Grant
    Filed: June 14, 1990
    Date of Patent: October 6, 1992
    Assignee: Xerox Corporation
    Inventors: Peter M. Kazmaier, James M. Duff, Gordon K. Hamer, Charles G. Allen, Sandra J. Gardner
  • Photoconductive imaging members with polycarbonate binders
    Patent number: 5080987
    Abstract: Block copolymers of the formula ##STR1## wherein R.sub.1, R.sub.2, and R.sub.3 are independently selected from the group consisting of hydrogen, alkyl and aryl; k, j, m and n represent the number of repeating segments, and imaging members thereof.
    Type: Grant
    Filed: July 2, 1990
    Date of Patent: January 14, 1992
    Assignee: Xerox Corporation
    Inventors: Peter G. Odell, Dasarao K. Murti, Charles G. Allen