Patents by Inventor Norbert Rossak

Norbert Rossak 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).

  • Use of a swellable plastic and process for making a resistive moisture sensor
    Patent number: 5348761
    Abstract: A process is disclosed for producing a swellable plastic resistive moisture sensor comprising dispersing an additive selected from the group consisting of carbon in powder, dust or soot form, carbon black, graphite, a metal in powder or dust form, and mixtures thereof, into a plastic comprising a polyimide or a copolyimide or both formed from diisocyanate and dianhydride reactants.
    Type: Grant
    Filed: February 28, 1992
    Date of Patent: September 20, 1994
    Assignees: E + E Elektronik Gesellschaft m.b.H., Lenzing Aktiengesellschaft
    Inventors: Helmut Mitter, Walter Scharizer, Herbert Sollradl, Norbert Rossak
  • Process for producing flame retardant high temperature resistant shaped articles
    Patent number: 5178810
    Abstract: A process for producing high-temperature resistant and flame-retardant shaped articles of polyimide polymers of the general formula ##STR1## wherein A represents a four-valent group and R represents a divalent aromatic group, by heating a manipulatable sheet-like structure to a temperature in the glass transition range of between 280.degree. C. and 360.degree. and pressing it at pressures ranging between 10 bar and 500 bar. The polyimide shaped bodies obtained have densities of at least 1.30 g/cm.sup.3. Preferably, they may be completed as sheets having uniform thicknesses of between 0.1 and 6 mm.
    Type: Grant
    Filed: March 30, 1990
    Date of Patent: January 12, 1993
    Assignee: Lenzing Aktiengesellschaft
    Inventors: Robert Vodiunig, Norbert Rossak, Manfred Schobesberger, Klaus Weinrotter