Patents by Inventor Walter Portmann

Walter Portmann 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).

  • Fillers dyed with polycationic dyestuffs useful for coloring paper and non-woven fabrics
    Patent number: 4543128
    Abstract: Coloring compositions comprising an aqueous paste or dispersion of a filler which has been dyed with a water-soluble polycationic dyestuff, preferably together with a binding agent, are used in the coating of paper and the fixing, dyeing and printing of non-woven fabrics, including tissue paper.
    Type: Grant
    Filed: August 23, 1983
    Date of Patent: September 24, 1985
    Assignee: Sandoz Ltd.
    Inventors: Juerg Troesch, Walter Portmann