Patents Assigned to Schwanhausser & Co. Schwan-Bleistift Fabrik
  • Ink
    Patent number: 4183685
    Abstract: The invention relates to an ink capable of producing writing or marking on a non-absorbent or impermeable surface, which can easily be wiped off. The disadvantages inherent in the known inks are overcome by adding ester compounds of a certain composition to the ink.
    Type: Grant
    Filed: October 6, 1977
    Date of Patent: January 15, 1980
    Assignee: Schwanhausser & Co. Schwan-Bleistift Fabrik
    Inventors: Hans J. Hofmann, Axel Jankewitz