Patents by Inventor Kenneth L. Dunlap

Kenneth L. Dunlap 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: 5349082
    Abstract: Disclosed herein is a process for recovering toluene diisocyanate (TDI) from a TDI residue solution, comprising mixing the residue solution with a polyisocyanate consisting essentially of methylenediphenyl diisocyanate (MDI) or MDI in combination with its higher ring oligomer, followed by heating the resulting mixture over a temperature range of 130.degree. to 250.degree. C. for a period of time sufficient to remove free TDI and thermally splittable TDI generated from equilibration of the TDI residue with MDI or the MDI oligomer by either a batch or continuous process.
    Type: Grant
    Filed: March 19, 1993
    Date of Patent: September 20, 1994
    Assignee: Miles Inc.
    Inventors: William E. Slack, Kenneth L. Dunlap, Larry W. Arndt, Louis Renbaum
  • Patent number: 5175350
    Abstract: The present invention is directed for preparing a 4,4'-diisocyanato dicyclohexylmethane which contain a relatively high amount of the trans,trans-isomer. The process broadly comprises (a) melting a mixture of 4,4'-diisocyanato dicyclohexyl-methane isomers, (b) cooling the melted mixture to form: (1) a liquid phase and (2) a solid phase, (c) removing said liquid phase, which is a commercially viable product itself, (d) heating the solid phase and removing that portion of the solid phase which has melted, and (e) recovering that portion of said solid phase which has not melted by heating the remaining portion.
    Type: Grant
    Filed: February 14, 1992
    Date of Patent: December 29, 1992
    Assignee: Miles Inc.
    Inventors: Stephen D. Seneker, Kenneth L. Dunlap, Michael K. Lowery, Terry A. Potter
  • Patent number: 4983763
    Abstract: The present invention is directed to a simple process for preparing a 4,4'-diisocyanato dicyclohexylmethane containing at least 90% by weight of the trans, trans-isomer. More particularly, the process comprises:(a) melting a mixture of 4,4'-diisocyanato dicyclohexylmethane isomers containing at least 30% by weight, and preferably from 45 to 55% by weight, of the trans,trans-isomer,(b) cooling the melted mixture to a temperature of from about 20.degree. to about 25.degree. C.
    Type: Grant
    Filed: April 19, 1990
    Date of Patent: January 8, 1991
    Assignee: Mobay Corporation
    Inventors: Stephen D. Seneker, Terry A. Potter, Kenneth L. Dunlap
  • Patent number: 4888442
    Abstract: The present invention is directed to a process for reducing the free monomer content of polyisocyanate adduct mixtures wherein the adduct has an average isocyanate functionality of greater than about 1.8 which comprises treating the polyisocyanate adduct mixture in the presence of 2 to about 30 percent by weight of an inert solvent, based on the weight of the polyisocyanate mixture, in an agitated thin-layer evaporator under conditions sufficient to reduce the free monomer content of the polyisocyanate adduct mixture below that level which is obtainable in the absence of a solvent.
    Type: Grant
    Filed: September 23, 1986
    Date of Patent: December 19, 1989
    Assignee: Mobay Corporation
    Inventors: Kenneth L. Dunlap, Peter H. Markusch, Clarence D. Ferrell
  • Patent number: 4810820
    Abstract: Aliphatic and/or cycloaliphatic polyisocyanates containing allophanate groups are produced by reacting (a) a di- and/or polyisocyanate with aliphatic and/or cycloaliphatic isocyanate groups with (b) a hydroxy compound at a temperature of at least 150.degree. C. for no more than 90 minutes and then rapidly cooling the reaction mixture to a temperature of less than 100.degree. C. It is preferred that the reaction be carried out in the absence of oxygen. The products thus obtained are virtually colorless, have a relatively low viscosity and excellent storage stability.
    Type: Grant
    Filed: August 12, 1987
    Date of Patent: March 7, 1989
    Assignee: Mobay Corporation
    Inventors: William E. Slack, Terry A. Potter, Kenneth L. Dunlap
  • Patent number: 4259526
    Abstract: The instant invention is directed to a process for the preparation of mixtures of polyamines of the polyamino-polyaryl-polymethylene type whereby the proportion or the ortho-substituted products are substantially increased. This increase is brought about by adding the acid catalyst to the aromatic amine/formaldehyde reaction mixture in two or more stages.
    Type: Grant
    Filed: February 21, 1979
    Date of Patent: March 31, 1981
    Assignees: Bayer Aktiengesellschaft, Mobay Chemical Corporation
    Inventors: Kenneth L. Dunlap, Hartmut Knofel