Patents by Inventor Knut Graef

Knut Graef 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: 6368725
    Abstract: Process for the preparation of a powder lacquer composition based on polyester by a) common or separate heating to a temperature of 120-200° C. of A) 99-40 wt. % polyester precondensates, and/or of monomers usable for the preparation thereof, B) 1-60 wt. % pigments and C) 0-10 wt. % wetting additives and/or further additives which are conventionally used for lacquers, wherein the percentages by weight total 100%, b) homogeneous mixing of the components A), B) and C) with the application of shear forces and with the heating temperature maintained, c) dispersion of the mixture obtained in a dispersing medium at a temperature equal to or above the melting temperature of the starting components A), B) and C) with further polycondensation of the polyester precondensate A), and/or of the monomers, d) cooling of the dispersion and addition of a conventional cross-linking agent for the polyester and optionally of conventional additives, within the temperature range 60 to 140° C.
    Type: Grant
    Filed: October 13, 2000
    Date of Patent: April 9, 2002
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Knut Gräf, Hans-Ulrich Simmrock, Alexandra Jacobs, Volker Mörs, Bennett Ward
  • Patent number: 5015688
    Abstract: Aqueous heat-curable coating substances in a polyester and acrylic resin base and a process for their manufacture. The new coating substances are usable as aqueous, heat-curable coatings and as clear varnish coating substances. The new heat-curable aqueous coating substances contain as binding agents 20 to 45%/weight of an amine resin cross-linking agent and 80 to 55%/weight of a polyester oligomer polyacrylate which is water-soluble following neutralization with bases and has a hydroxyl value of 150 to 390 and an acid value of 16 to 40, manufactured by the radical polymerization of a hydroxyfunctional (meth) acrylic acid ester, a monofunctional ethylenically unsaturated acid and, if required, an .alpha., .beta. ethylenically unsaturated monomer with no functional groups, in a polyester oligomer.
    Type: Grant
    Filed: October 26, 1989
    Date of Patent: May 14, 1991
    Assignee: Herbertsgesellschaft GmbH
    Inventors: Klaus Bederke, Volker Ducoffre, Knut Graef