Patents by Inventor Franz R. Widmer

Franz R. Widmer 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).

  • Coating compositions for the manufacture of coated papers
    Patent number: 4367171
    Abstract: A coating composition for paper is provided, which composition consists of an aqueous preparation containing at least a polymeric binder, an inorganic pigment, and a water-insoluble urea-formaldehyde polycondensation product from 1 mole of urea and 1.3 to 2 moles, of formaldehyde, which product is in a highly dispersed form and has a mean particle diameter of 3 to 6 microns, and a specific BET surface urea of 3 to 12 m.sup.2 /g.Papers coated with these compositions exhibit, in addition to an enhanced degree of whiteness and equally good gloss and improved opacity and smoothness, above all better printability.
    Type: Grant
    Filed: June 19, 1979
    Date of Patent: January 4, 1983
    Assignee: Ciba-Geigy AG
    Inventors: Klaus D. Leifels, Alfred Renner, Franz R. Widmer