Patents by Inventor Peter Leifert

Peter Leifert 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).

  • Method for the production of paper, paperboard and cardboard
    Patent number: 8029647
    Abstract: Process for the production of paper, board and cardboard by draining a paper stock on a wire with sheet formation and drying of the sheets, the sheet formation being carried out in the absence of finely divided inorganic flocculants and (a) polymers comprising vinylamine units and/or polyvinylformamide having a molar mass Mw of, in each case, at least 1 million and (b) at least one cationic or nonionic polyacrylamide and/or one cationic or nonionic polymethacrylamide having a molar mass Mw of, in each case, at least 2.5 million being used as retention aids.
    Type: Grant
    Filed: September 8, 2005
    Date of Patent: October 4, 2011
    Assignee: BASF Aktiengesellschaft
    Inventors: Marc Leduc, Rainer Blum, Peter Leifert
  • Method for the Production of Paper, Paperboard and Cardboard
    Publication number: 20080000601
    Abstract: Process for the production of paper, board and cardboard by draining a paper stock on a wire with sheet formation and drying of the sheets, the sheet formation being carried out in the absence of finely divided inorganic flocculants and (a) polymers comprising vinylamine units and/or polyvinylformamide having a molar mass Mw of, in each case, at least 1 million and (b) at least one cationic or nonionic polyacrylamide and/or one cationic or nonionic polymethacrylamide having a molar mass Mw of, in each case, at least 2.5 million being used as retention aids.
    Type: Application
    Filed: September 8, 2005
    Publication date: January 3, 2008
    Applicant: BASF Aktiengesellschaft
    Inventors: Marc Leduc, Rainer Blum, Peter Leifert