Patents by Inventor John T. Alston

John T. Alston 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).

  • Liquid ink jet ink
    Patent number: 5453121
    Abstract: An ink jet ink composition comprising a liquid having an electrical resistance of at least 10.sup.9 Ohm.cm, insoluble marking particles in a range of from 0.5% to 30% by weight and a particle charging agent in a range of from 0.05 to 5% by weight, where the marking particles are capable of being charged and concentrated into agglomerations of the particles and ejected from the ink in the presence of non-uniform electrostatic field of significant gradient in an ink jet printing apparatus.
    Type: Grant
    Filed: June 30, 1994
    Date of Patent: September 26, 1995
    Assignee: Tonejet Corporation Pty Ltd.
    Inventors: Stephen L. Nicholls, John T. Alston
  • Electrostatic proofing of negative color separations
    Patent number: 5055365
    Abstract: An image reversal process for the production of electrophotographic color proofs from negative separation films where the photoconductive recording member is reusable and the proofs are produced on printing stock paper and which very closely match the appearance of the printed sheet.
    Type: Grant
    Filed: November 28, 1988
    Date of Patent: October 8, 1991
    Assignee: Stork Colorproofing B.V.
    Inventors: Josef Matkan, John T. Alston