Patents by Inventor Daniel E. Saddoris

Daniel E. Saddoris 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 of making soluble squaraine dyes
    Patent number: 5625062
    Abstract: The present invention provides a novel process for the production of organic solvent soluble squaraine dyes. More specifically, the invention describes how a difficult to prepare tetrahydroxy squaraine intermediate can be prepared in an organic solvent system in the presence of water. This intermediate can then be esterified in pyridine to form the soluble squaraine dye which can then be easily isolated from the reaction mixture. The invention also provides the dyes prepared according to this method.
    Type: Grant
    Filed: May 29, 1996
    Date of Patent: April 29, 1997
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Roger A. Mader, William D. Ramsden, Terence D. Spawn, Daniel E. Saddoris