Patents by Inventor David C. Zecher

David C. Zecher 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).

  • Chemically-initiated inverse emulsion polymerization with Na, Li/Cl, Br salt
    Patent number: 4379883
    Abstract: A chemically initiated water-in-oil emulsion polymerization process is disclosed for making water-soluble anionic copolymers from water-soluble, ethylenically unsaturated, addition polymerizable monomers. Improved products are obtained by adding a water-soluble salt to the aqueous phase of the water-in-oil emulsion prior to polymerization.
    Type: Grant
    Filed: August 4, 1981
    Date of Patent: April 12, 1983
    Assignee: Hercules Incorporated
    Inventor: David C. Zecher
  • Process for inhibiting corrosion of metals in aqueous systems
    Patent number: 4093557
    Abstract: A process for inhibiting corrosion of metals in contact with aqueous systems is provided by maintaining in contact with metals a corrosion inhibiting composition that contains a compound containing the quinomethide group represented as follows: ##STR1##
    Type: Grant
    Filed: September 16, 1976
    Date of Patent: June 6, 1978
    Assignee: Hercules Incorporated
    Inventor: David C. Zecher
  • Corrosion inhibitor composition
    Patent number: 4014814
    Abstract: A composition for use as corrosion inhibitor in circulating water streams includes a linear water-soluble, phenol-aldehyde resinous condensation product and a polyphospate, such as an alkali metal polyphosphate or a phosphorylated polyol.
    Type: Grant
    Filed: July 30, 1975
    Date of Patent: March 29, 1977
    Assignee: Hercules Incorporated
    Inventor: David C. Zecher