Patents by Inventor Dirk Jacques Dijkstra

Dirk Jacques Dijkstra 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).

  • Polycarbonate with high extensional viscosity
    Patent number: 6713594
    Abstract: A thermoplastic molding composition that contains a polycarbonate resin having specific extensional Theological properties is disclosed. The composition is particularly suitable for preparing containers.
    Type: Grant
    Filed: March 24, 2003
    Date of Patent: March 30, 2004
    Assignee: Bayer Aktiengesellschaft
    Inventors: Klaus Horn, Ralf Hufen, Markus Krieter, Dirk-Jacques Dijkstra, Jens Hepperle, Helmut Münstedt
  • Plastic containers with uniform wall thickness
    Publication number: 20030209553
    Abstract: A container having uniform wall thickness, molded of a thermoplastic composition is disclosed. The wall of the container at its thickest being at most three times as thick as at its thinnest. Also disclosed is a process for the preparation of the container. The process entails extrusion blow molding or injection stretch blow molding of a thermoplastic material characterized in that at a temperature of 200° C., its S value is greater than 1.1 at a Hencky elongation &egr; of 2.0 and an elongation rate range {dot over (&egr;)} of between 0.1 and 0.01, and its S value is greater than 1.1 at a Hencky elongation &egr; of 2.5 and an elongation rate range {dot over (&egr;)} of between 0.1 and 0.01, wherein S is &eegr;E divided by 3&eegr;.
    Type: Application
    Filed: March 24, 2003
    Publication date: November 13, 2003
    Inventors: Klaus Horn, Ralf Hufen, Markus Krieter, Dirk-Jacques Dijkstra, Jens Hepperle, Helmut Munstedt
  • Polycarbonate with high extensional viscosity
    Publication number: 20030181628
    Abstract: A thermoplastic molding composition that contains a polycarbonate resin having specific extensional rheological properties is disclosed. The composition is particularly suitable for preparing containers.
    Type: Application
    Filed: March 24, 2003
    Publication date: September 25, 2003
    Inventors: Klaus Horn, Ralf Hufen, Markus Krieter, Dirk-Jacques Dijkstra, Jens Hepperle, Helmut Munstedt
  • Thermoplastic material consisting of aliphatic carbamic acid derivatives of polysaccharides and low-molecular urea derivatives as well as a process for their preparation and use of the same
    Patent number: 6403787
    Abstract: The present invention relates to evenly substituted polysaccharide derivatives having the general structure: polysaccharide—O—R wherein polysaccharide—O represents a substituted or unsubstituted polysaccharide unit and R is a substituent of a polysaccharide-OH group having either the structure R=—A—B— or the structure R=—B—, wherein A is a linear polyether chain having the following structure: A=(—D—O—)n wherein D denotes a linear aliphatic branched or unbranched chain having 2 to 12 C atoms, O represents an oxygen atom and n is a number equal to or greater than 1, and B represents a substituted carbamic acid having the structure wherein E denotes a linear or branched aliphatic chain having 1 to 18 C atoms.
    Type: Grant
    Filed: April 2, 1997
    Date of Patent: June 11, 2002
    Assignee: Wolff Walsrode AG
    Inventors: Jürgen Engelhardt, Joachim Simon, Hanns-Peter Müller, Rainhard Koch, Dirk-Jacques Dijkstra
  • Polysaccharide-based thermoplastic material, process for preparing the same and method of use thereof
    Patent number: 6362330
    Abstract: The present invention relates to novel thermoplastic materials based on polysaccharide ethers which are simultaneously substituted by carboxylic acid ester groups and carbamate groups, together with mixtures of such derivatives with low molecular weight aliphatic urea derivatives.
    Type: Grant
    Filed: November 1, 1999
    Date of Patent: March 26, 2002
    Assignee: Wolff Wolsrode AG
    Inventors: Joachim Simon, Hanns-Peter Müller, Dirk Jacques Dijkstra, Gunter Weber
  • THERMOPLASTIC MATERIAL CONSISTING OF ALIPHATIC CARBAMIC ACID DERIVATIVES OF POLYSACCHARIDES AND LOW-MOLECULAR UREA DERIVATIVES AS WELL AS A PROCESS FOR THEIR PREPARATION AND USE OF THE SAME
    Publication number: 20010007027
    Abstract: The present invention relates to evenly substituted polysaccharide derivatives having the general structure:
    Type: Application
    Filed: April 2, 1997
    Publication date: July 5, 2001
    Inventors: JURGEN ENGELHARDT, JOACHIM SIMON, HANNS-PETER MULLER, RAINHARD KOCH, DIRK-JACQUES DIJKSTRA
  • Compostable and thermoplastic cellulose ether-2-hydroxycarboxylic acid esters and mixed esters
    Patent number: 5861506
    Abstract: Thermoplastic and compostable cellulose ether esters with 2-hydroxycarboxylic acids as acid components and mixed esters which, in addition to 2-hydroxycarboxylic acid groups, have further mono-, dicarboxylic acid or carbamate groups.
    Type: Grant
    Filed: May 7, 1997
    Date of Patent: January 19, 1999
    Assignee: Wolff Walsrode AG
    Inventors: Joachim Simon, Hanns Peter Muller, Rainhard Koch, Dirk Jacques Dijkstra, Jurgen Engelhardt, Volkhard Muller
  • Thermoplastically workable, biodegradable moulding compositions
    Patent number: 5698612
    Abstract: The present invention provides thermoplastically workable and completely biodegradable moulding compositions, a process for the preparation thereof and the use thereof as biodegradable materials for the production of, for example, injection-moulded parts, films, fibres or coatings.
    Type: Grant
    Filed: December 11, 1996
    Date of Patent: December 16, 1997
    Assignee: Bayer Akteingesellschaft
    Inventors: Joachim Simon, Hanns Peter Muller, Dirk Jacques Dijkstra, Jurgen Engelhardt, Volkhard Muller, Gunter Weber