Patents by Inventor Stephen J. Hannam

Stephen J. Hannam 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).

  • Production of N,N,N',N'-tetraacetylethylenediamine
    Patent number: 4356321
    Abstract: N,N,N',N'-tetraacetylethylenediamine is made by reacting N,N'-diacetylethylenediamine with acetic anhydride and thereby forming a reaction mixture of N,N,N',N'-tetraacetylethylenediamine and acetic acid and anhydride, and distilling off acetic acid and working up the distillation residue to give substantially pure N,N,N',N'-tetraacetylethylenediamine.
    Type: Grant
    Filed: February 8, 1982
    Date of Patent: October 26, 1982
    Assignee: Warwick Chemical Limited
    Inventor: Stephen J. Hannam
  • Process for making N,N,N',N'-tetraacetylethylenediamine
    Patent number: 4354042
    Abstract: N,N,N',N'-tetraacetylethylenediamine (TAED) is made by an improved multicyclic process, which comprises, in each cycle, the steps of reacting N,N'-diacetylethylenediamine (DAED) with acetic anhydride and thereby forming a reaction mixture of N,N,N',N'-tetraacetylethylenediamine and acetic acid and anhydride, and distilling off acetic acid and working up the distillation residue to give substantially pure N,N,N',N'-tetraacetylethylenediamine, and in which the molar ratio of DAED:acetic anhydride in each cycle is at least 1:6.
    Type: Grant
    Filed: December 8, 1980
    Date of Patent: October 12, 1982
    Assignee: Warwick Chemical Limited
    Inventors: Stephen J. Hannam, John S. Saynor, Anthony D. Watling
  • Cyclic compounds synthesis
    Patent number: 3950386
    Abstract: A one-step simultaneous esterification and halogenation process results in novel compounds having flame retardant properties.
    Type: Grant
    Filed: April 19, 1974
    Date of Patent: April 13, 1976
    Assignee: Sun Chemical Corporation
    Inventor: Stephen J. Hannam