Patents by Inventor Sheau-Hwa Ma

Sheau-Hwa Ma 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).

  • Method for diffusion patterning
    Patent number: 5209814
    Abstract: Method for patterning organic polymer layers comprising the sequential steps:A. Applying to a substrate an unpatterned layer of acidic polymer dissolved in a plasticizer,B. Applying to the unpatterned layer a second patterned layer which is a liquid solution of organic base dissolved in a volatile solvent;C. Heating the patterned layer to effect removal of the volatile solvent from the layer and diffusion of the second layer plasticizer and organic base into the underlying areas of the acidic polymer layer; andD. Washing the layers with aqueous solution to effect solubilization of the acidic polymer underlying the patterned areas and removal therefrom of the solubilized polymer and plasticizers.
    Type: Grant
    Filed: September 30, 1991
    Date of Patent: May 11, 1993
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: John J. Felten, Sheau-Hwa Ma
  • Aqueous pigmented inks for ink jet printers
    Patent number: 5085698
    Abstract: A pigmented ink for ink jet printers which comprises an aqueous carrier medium, and pigment particles dispersed in an AB or BAB block copolymer having a hydrophilic segment and a segment that links to the pigment. The A block and the B block(s) have molecular weights of at least 300. These inks give images having good print quality, water and smear resistance, lightfastness, and storage stability.
    Type: Grant
    Filed: April 11, 1990
    Date of Patent: February 4, 1992
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Sheau-Hwa Ma, Howard Matrick, Arthur C. Shor, Harry J. Spinelli
  • Donor element for thermal imaging containing infra-red absorbing squarylium compound
    Patent number: 5019549
    Abstract: These is disclosed donor elements for laser-induced thermal imaging processes containing infra-red absorbing squarylium dyes of the following structure: ##STR1## wherein R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are each independently alkyl groups of from one to eight carbon atoms.
    Type: Grant
    Filed: October 25, 1990
    Date of Patent: May 28, 1991
    Inventors: Reid E. Kellogg, Evan D. Laganis, Sheau-Hwa Ma