Patents by Inventor Augustinus E. H. de Keijzer

Augustinus E. H. de Keijzer 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: 6342548
    Abstract: The invention is concerned with a flame retardant polyamide composition in which melam is the flame retardant component. Very advantageous are polyamide compositions having a melting temperature of at least 260° C. preferably 280° C. in which for the first time with a non-halogen containing flame retardant at relatively low concentration high flame retardancy ratings can be obtained. Preferably the melam contains less then 2.0% by weight residual catalyst. The compositions are useful for cablecoatings, tubing, films, fibers and electric or electronic components.
    Type: Grant
    Filed: June 2, 1997
    Date of Patent: January 29, 2002
    Assignee: DSM N.V.
    Inventors: Peter Flippo, Johannes Tijssen, Chi K. Sham, Augustinus E. H. de Keijzer, Richerdus J. M. Hulskotte
  • Patent number: 6051708
    Abstract: A process for the preparation of a melamine condensation product comprising the step of heating a starting material comprising melamine or a melamine salt in the presence of: (i) at least one organic acid, (ii) at least one ammonia or melamine salt of the organic acid, or (iii) a mixture of (i) and (ii), under reaction conditions effective for the formation of the melamine condensation product. The melamine condensation product with a residual condensation agent content of less than 1 wt. % is useful in a moldable polymer composition possessing flame-retardant properties.
    Type: Grant
    Filed: March 4, 1998
    Date of Patent: April 18, 2000
    Assignee: DSM N.V.
    Inventors: Augustinus E.H. de Keijzer, Bernardus J.H. Dijkstra
  • Patent number: 5985960
    Abstract: A process for the preparation of a melamine condensation product comprising the step of heating a starting material comprising melamine or a melamine salt in the presence of: (i) at least one organic acid, (ii) at least one ammonia or melamine salt of the organic acid, or (iii) a mixture of (i) and (ii), under reaction conditions effective for the formation of the melamine condensation product. The melamine condensation product with a residual condensation agent content of less than 1 wt. % is useful in a moldable polymer composition possessing flame-retardant properties.
    Type: Grant
    Filed: June 2, 1997
    Date of Patent: November 16, 1999
    Assignee: DSM N.V. Octroolbureau
    Inventors: Augustinus E. H. de Keijzer, Bernardus J. H. Dijkstra