Patents by Inventor Loretta Ann G. Page

Loretta Ann G. Page 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: 5035972
    Abstract: Negative-working electrostatic liquid developer consisting essentially of(A) nopolar liquid having Kauri-butanol value less than 30, present in major amount,(B) thermoplastic resin particles having an average particle size by area of less than 10 .mu.m, and(C) an AB diblock copolymer charge director compound as defined. Optionally a colorant and charge adjuvant are present. The process of making the electrostatic liquid developer is described. The electrostatic liquid developer is useful in copying, making proofs including digital color proofs, lithographic printing plates, and resists.
    Type: Grant
    Filed: October 31, 1989
    Date of Patent: July 30, 1991
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Lyla M. El-Sayed, Loretta Ann G. Page
  • Patent number: 5002848
    Abstract: A positive-working electrostatic liquid developer consisting essentially of (A) a nonpolar liquid having a Kauri-butanol value of less than 30, present in major amount, (B) thermoplastic resin particles, less than 10 .mu.m average by area particle size, (C) a nonpolar liquid soluble ionic or zwitterionic charge director compound, and (D) a substituted carboxylic acid or salt adjuvant as defined. Component (D) can be present in liquid (A) or dispersed in the resin particles. The process of preparation of the electrostatic liquid developer is described. The liquid developers are useful in copying, color proofing including digital color proofing, lithographic printing plates and resists.
    Type: Grant
    Filed: September 5, 1989
    Date of Patent: March 26, 1991
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Lyla M. El-Sayed, Loretta Ann G. Page, Kathryn A. Pearlstine