Patents by Inventor Doretta Agostine

Doretta Agostine 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).

  • Toner compositions with inner salt charge enhancing additives
    Patent number: 4752550
    Abstract: Toner compositions comprised of resin particles, pigment particles, and as a charge enhancing additive inner salts wherein the negative charge center is covalently attached to the positive charge center. Also disclosed are developer compositions comprised of the aforementioned toner components and carrier particles, which compositions are particularly useful for the development of the electrostatic latent images. Additionally, there can be selected for the toner and developer compositions mixtures of charge enhancing additives including mixtures of the aforementioned inner salts and second charge enhancing additives such as quaternary ammonium compounds.
    Type: Grant
    Filed: December 5, 1986
    Date of Patent: June 21, 1988
    Assignee: Xerox Corporation
    Inventors: Angelo J. Barbetta, Doretta Agostine, Thomas R. Hoffend, Richard D. Manca, Emery G. Tokoli
  • Electrophotographic toner compositions containing novel imide charge control _additives
    Patent number: 4493883
    Abstract: Disclosed are positively charged toner compositions comprised of resin particles, pigment particles, and imide charge enhancing additives of the formula: ##STR1## wherein R.sub.1, R.sub.2, and R.sub.3, are alkyl groups containing from 1 carbon atom to about 25 carbon atoms, R.sub.4 is selected from the group consisting of hydrogen, nitro, halogen, amino, and alkyl and A is an anion.
    Type: Grant
    Filed: February 21, 1984
    Date of Patent: January 15, 1985
    Assignee: Xerox Corporation
    Inventors: Robert J. Gruber, Doretta Agostine, Paul C. Julien, Raymond A. Yourd, III
  • Nitrogen containing polymers as charge enhancing additive for electrophotographic toner
    Patent number: 4415646
    Abstract: This invention is directed to positively charged developer compositions and toner compositions, the toner composition being comprised of resin particles, pigment particles, and from about 0.1 to about 10 percent by weight of the toner particles of a polymeric charge enhancing additive selected from the group consisting of those additives of the following formulas: ##STR1## wherein a and b are percentage numbers equaling 100, a being from about 20 weight percent to about 99 weight percent, and b being from about 80 weight percent to about 1 weight percent, n is a repeating number ranging from about 3 to about 300, Z is an oxygen atom, c is the number zero or 1, Y is an alkyl or aromatic radical, Z' is selected from the group consisting of aliphatic, aromatic, and heterocyclic radicals, R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are independently selected from alkyl radicals containing from about 1 to about 22 carbon atoms, X is an anion, a' is a number of from about 50 to about 500, R.sub.
    Type: Grant
    Filed: March 3, 1982
    Date of Patent: November 15, 1983
    Assignee: Xerox Corporation
    Inventors: Robert J. Gruber, Steven B. Bolte, Doretta Agostine