Patents by Inventor Donald R. Hollingsworth

Donald R. Hollingsworth 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).

  • Portable underwater viewer with magnifying capabilities
    Patent number: 6023382
    Abstract: An underwater viewing apparatus is provided including a housing with a hollow configuration. Also included is a lens assembly comprising a magnifying lens secured within the housing for magnifying items beneath the housing when viewed through the housing.
    Type: Grant
    Filed: May 28, 1998
    Date of Patent: February 8, 2000
    Inventors: Donald R. Hollingsworth, Chester W. Champion
  • Polyether glycol production by polymerization of tetrahydrofuran
    Patent number: 5262562
    Abstract: A method is disclosed wherein tetrahydrofuran is reacted in the presence of acetic anhydride and a catalyst to provide acetate derivatives of polyglycols and using as a catalyst a triflic acid-modified montmorillonite clay at a temperature of 0.degree.-1000.degree. C. and atmospheric pressure.
    Type: Grant
    Filed: February 14, 1992
    Date of Patent: November 16, 1993
    Assignee: Texaco Chemical Company
    Inventors: Donald R. Hollingsworth, John F. Knifton
  • Method for 1,2-substituted imidazoline compositions
    Patent number: 5214155
    Abstract: This invention is a method for making 1,2-substituted imidazoline compositions utilizing a polyamine mixture containing a high concentration of linear polyamine. The polyamine is either triethylenetetramine or tetraethylenepentamine. The polyamine mixture is reacted with a fatty acid, fatty dimer acid or the fatty esters thereof to yield the 1,2-substituted imidazoline composition. The highly linear polyamine provides higher yields of the imidazoline compound in the composition.
    Type: Grant
    Filed: April 29, 1992
    Date of Patent: May 25, 1993
    Assignee: Texaco Chemical Company
    Inventors: Donald R. Hollingsworth, Jeffrey H. Edwards