Patents by Inventor Ellen A. Langford

Ellen A. Langford 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: 4973532
    Abstract: A battery separator includes a porous substrate and a thermal fuse material adhered to at least one surface of said porous substrate. The thermal fuse material is adhered to the substrate surface in a predetermined geometric array thereupon so as to establish open areas of the at least one substrate surface to thereby allow ionic migration therethrough. The thermal fuse material forming the geometric array on the substrate surface may itself define open pores to further facilitate such ionic migration. The thermal fuse material melts at or near a predetermined threshold temperature so that the substrate's permeability irreversibly becomes significantly decreased and thus interrupts the chemical reaction in an electrochemical battery. In such a manner, batteries of improved safety may be provided using the separators of this invention.
    Type: Grant
    Filed: April 5, 1989
    Date of Patent: November 27, 1990
    Assignee: Hoechst Celanese Corporation
    Inventors: Henry T. Taskier, Steven M. Mullins, Ellen A. Langford, Robert J. Fleming
  • Patent number: 4868324
    Abstract: Crude diphenyl phthalates, including isomeric mixtures thereof which are prepared by reacting mixtures of isophthalic and terephthalic acids with phenol, preferably in the presence of an organotitanate, organozirconate, or organostannate catalyst, are purified by dissolving the crude phthalate in an organic solvent, contacting the resulting solution with dilute aqueous alkali to neutralize the ester, separating the resulting oil and aqueous phases, and thereafter recovering from the oil phase a purified diaryl phthalate of reduced color and low acidity.
    Type: Grant
    Filed: May 24, 1988
    Date of Patent: September 19, 1989
    Assignee: Celanese Engineering Resins, Inc.
    Inventors: A. Lee Stautzenberger, Ellen A. Langford, Edward E. Quick
  • Patent number: 4766236
    Abstract: Color properties of crude phenolic esters of aromatic dicarboxylic acids are improved by distilling the esters in the presence of a boron oxide compound.
    Type: Grant
    Filed: June 30, 1987
    Date of Patent: August 23, 1988
    Assignee: Hoechst Celanese Corporation
    Inventors: A. Lee Stautzenberger, Ellen A. Langford