Patents by Inventor Rudolf J. Tenhagen

Rudolf J. Tenhagen 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).

  • Process for preparing polyurethane foams having zones of differing hardness
    Patent number: 4965029
    Abstract: A process for preparing a polyurethane foamed article including a hard foam encapsulated by a soft foam is provided. The process provides improved encapsulation over that described in EP 68820 by frothing the hard foam formulation, with for example carbon dioxide, before it is introduced onto the rising soft foam formulation. The hard foam formulation is frothed so that is density is between 75% and 145% of the soft foam formulation.
    Type: Grant
    Filed: January 22, 1988
    Date of Patent: October 23, 1990
    Assignee: Polyol International BV
    Inventors: Werner A. Lidy, Rudolf J. Tenhagen
  • Process for making polyurethane foam
    Patent number: 4714574
    Abstract: A flexible polyurethane foam article with regions of different hardness is made by introducing into a mould a foam formulation giving a foam of a given hardness and then introducing a foam formulation giving a foam of different hardness directly onto the first foam formulation at a time corresponding to a volume expansion in the range 100% to 2300%.
    Type: Grant
    Filed: February 9, 1983
    Date of Patent: December 22, 1987
    Assignee: BP Chemicals Limited
    Inventor: Rudolf J. Tenhagen
  • Equipment for mixing liquid reactants
    Patent number: 4595565
    Abstract: A mixing head suitable for mixing two or more liquids is provided. During the mixing process, the liquids are first contacted in a zone of small dimensions in which turbulent mixing occurs and are then discharged into a zone of larger dimensions in which laminar flow is established. The two zones are so designed that there is a single piston operating in both zones and discharging the mixed product. The mixing head can be used to mix a polyol and a polyisocyanate during the formation of polyurethanes.
    Type: Grant
    Filed: August 29, 1984
    Date of Patent: June 17, 1986
    Assignee: BP Chemicals Limited
    Inventor: Rudolf J. Tenhagen
  • Flexible polyurethane foams having substantial number of cells with internal residual cell surface of 60 to 90 percent
    Patent number: 4304872
    Abstract: A novel flexible polyurethane foam has a substantial number of cells with an internal residual cell surface greater than 60% and less than 90%. The novel foams have improved vibration damping characteristics.
    Type: Grant
    Filed: April 24, 1980
    Date of Patent: December 8, 1981
    Assignee: BP Chemicals Limited
    Inventor: Rudolf J. Tenhagen
  • Process for preparing cold-cured molded polyurethane flexible from a high molecular weight siloxane and a solvent
    Patent number: 4276385
    Abstract: Cold-cured molded polyurethane flexible foams having improved vibration damping properities are made by foaming in the presence of (1) a high molecular weight predominantly linear siloxane polyoxyalkylene block copolymer and (2) a solvent which is compatible with the block copolymer and which has a viscosity of 3 to 100 cps and a surface tension between 15 to 60 dynes/cm.
    Type: Grant
    Filed: April 18, 1980
    Date of Patent: June 30, 1981
    Assignee: BP Chemicals Limited
    Inventor: Rudolf J. Tenhagen