Patents by Inventor Charles L. Allyn

Charles L. Allyn 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: 4065421
    Abstract: This invention relates to a process for the continuous production of aqueous urea-formaldehyde solutions having a mol ratio of formaldehyde to urea ranging from about 4.0 to about 6.0 and having a total solids content ranging from about 60% to about 85% by weight. This process utilizes a single multiple tray absorption column through which is passed the gaseous product from a formaldehyde converter counter current to a flow of aqueous urea solution. The column is maintained at a temperature ranging from about 40.degree. C to about 80.degree. C and dilute aqueous base is added at several points along the tower. Formaldehyde combines with the urea in the solution during their respective passages through the column to form the final product. A portion of the final product is circulated through the lower portion of the column.
    Type: Grant
    Filed: March 17, 1976
    Date of Patent: December 27, 1977
    Assignee: Reichhold Chemicals, Inc.
    Inventors: Charles L. Allyn, James C. Manlove, Gerald M. Chang, Robert C. Burmark