Patents by Inventor Hans-Josef Hoffmann

Hans-Josef Hoffmann 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: 5976402
    Abstract: Compositions containing p-dinitrosobenzene deposited onto a support of a chemically inert material which is solid at room temperature are provided. The composition is preferably formed by depositing p-dinitrosobenzene from a solution or by sublimation or in the course of its synthesis in the presence of one or more supports. Hydrophilic or hydrophobic silica, hydrophobicized zeolites, carbon blacks and layer silicates are examples of supports. The composition is useful in the production of adhesives, more particularly for bonding elastomers, e.g. in the polymerization or crosslinking of elastomers, and even more particularly in the bonding of rubber to metal.
    Type: Grant
    Filed: October 3, 1995
    Date of Patent: November 2, 1999
    Assignee: Henkel Kommanditgesellschaft auf Aktien (KGaA)
    Inventors: Burkhard Muller, Brigitte Calaminus, Wolf-Dieter Beiersdorf, Werner Gruber, Hans-Josef Hoffmann, Rainer Wefringhaus, Peter Kuhm, Norbert Hubner, Christian Block
  • Patent number: 5073588
    Abstract: An aqueous solution of suspension of glycidoxypropyl silanol and polydimethyl siloxanes having a number average molecular wieght of more than 100,000 and their use as mold release agents with good release values over a relatively large number of molding cycles in the molding of rubber and plastics.
    Type: Grant
    Filed: August 31, 1988
    Date of Patent: December 17, 1991
    Assignee: Henkel Kommanditgesellschaft auf Aktien
    Inventors: Hans-Guenter Seltmann, Juergen Haerer, Hans-Josef Hoffmann
  • Patent number: 4918119
    Abstract: A moisture-hardening flocking adhesive composition for application to elastomers. The adhesive contains an isocyanate terminated polyurethane prepolymer, an aromatic dinitroso compound and an essentially hydroxyl-free epoxy resin having an epoxide value of from about 0.45 to about 0.75. The composition is essentially free of highly volatile organic solvents. The composition is characterized as having improved storage stability and provides excellent adhesion between elastomeric substrates and flocking fibers, even after exposure to water.
    Type: Grant
    Filed: August 10, 1988
    Date of Patent: April 17, 1990
    Assignee: Henkel Kommanditgesellschaft auf Aktien
    Inventors: Hans-Guenter Seltmann, Hans-Josef Hoffmann, Hartmut Lippert
  • Patent number: 4670057
    Abstract: The invention relates to a new primer for pretreating glass in readiness for waterproof bonding to other substrates. The primer contains resins, functional silanes, solvents, and organosilazanes and, if desired, polyfunctional isocyanates and other additives. Compared with conventional primers, the resistance of the bond to hydrolysis is significantly improved.
    Type: Grant
    Filed: January 8, 1985
    Date of Patent: June 2, 1987
    Assignee: Henkel Kommanditgesellschaft auf Aktien
    Inventors: Riza N. Oezelli, Hans-Josef Hoffmann, Hans-Peter Kohlstadt
  • Patent number: 4535121
    Abstract: An adhesive for flocking elastomers, more especially apolar elastomers, such as EPDM. The adhesive contains an isocyanate-terminated polyurethane prepolymer and, as an adhesion promoter, a reaction product of an aromatic diisocyanate with a polyfunctional epoxide, particularly triglycidyl isocyanurate. The strength of adhesion and resistance of the bonds can be further increased by the addition of aromatic nitroso compounds, for example, 1,4-dinitrosobenzene.
    Type: Grant
    Filed: June 20, 1984
    Date of Patent: August 13, 1985
    Assignee: Henkel Kommanditgesellschaft auf Aktien
    Inventors: Riza N. Oezelli, Hans-Josef Hoffmann, Hartmut Lippert