Patents by Inventor Helmar Aigner

Helmar Aigner 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).

  • Multilayer filter material, process for its manufacture and the use thereof
    Patent number: 4661255
    Abstract: A multilayer filter material is described which comprises a coarse and a fine filter layer, while the individual filter layers contain a share of natural fibres and are interconnected with each other on the paper machine, without the use of a bonding agent, whereby the coarse filter layer consists of a mixture of natural and synthetic fibres and at least one part of said synthetic fibres is structured, and synthetic fibres lying on the surface of the coarse filter layer protrude from the plane of the filter material.Moreover a process for the manufacture of the multilayer filter material and its use is described.The inventive multilayer filter material is distinguished against comparable conventional filters by an increased service life and a better degree of separation.
    Type: Grant
    Filed: April 16, 1986
    Date of Patent: April 28, 1987
    Assignee: Gessner & Co. GmbH
    Inventors: Gunther Aumann, Helmar Aigner, Hans-Karl Schuster