Patents by Inventor Volker Graap, deceased

Volker Graap, deceased 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).

  • Apparatus for the manufacture of biaxially stretched flat film
    Patent number: 4625372
    Abstract: An apparatus is disclosed for the fabrication of a biaxially stretched flat film of thermoplastic material, particularly of polypropylene, with improved properties for a process in which the material is first partially pre-stretched in a longitudinal direction and, thereafter, simultaneously biaxially (longitudinally and laterally) stretched, the apparatus comprising stretching rollers for effecting partial longitudinal stretching of the film, the rollers being arranged upstream of an assembly for effecting simultaneous biaxial stretching of the film. The speed of the stretching rollers is infinitely variable so as to influence the total degree of film-stretching only by changing the speed of the rollers. The rollers used for longitudinal pre-stretching are arranged at the inlet section of the biaxial stretching assembly.
    Type: Grant
    Filed: March 22, 1985
    Date of Patent: December 2, 1986
    Assignee: Internationale Octrooi Maatschappij "Octropa" B.V.
    Inventors: Walter Hufnagel, Volker Graap, deceased, Freidrich von und zu Aufsess, Rotger Armsen
  • Method for the manufacture of biaxially stretched polyolefin film
    Patent number: 4261944
    Abstract: A method is disclosed for the manufacture of a biaxially stretched polyolefin film, particularly a polypropylene film, having improved properties, in which the material is first partially prestretched in a longitudinal direction and, thereafter, simultaneously biaxially (longitudinally and laterally) stretched, the apparatus comprising stretching rollers for effecting partial longitudinal stretching of the film, the rollers being arranged upstream of an assembly for effecting simultaneous biaxial stretching of the film. The speed of the stretching rollers is infinitely variable so as to influence the total degree of film-stretching only by changing the speed of the rollers. The rollers used for longitudinal prestretching are arranged at the inlet section of the biaxial stretching assembly.
    Type: Grant
    Filed: November 27, 1978
    Date of Patent: April 14, 1981
    Assignee: Lever Brothers Company
    Inventors: Walter Hufnagel, Volker Graap, deceased, Friedrich F. von und zu Aufsess, Rotger Armsen