Patents by Inventor Sten Frölich

Sten Frölich 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).

  • Process for production of paper
    Patent number: 7488402
    Abstract: The invention related to process for the production of paper from an aqueous suspension containing cellulosic fibers, and optional fillers, which comprises adding to the suspension (i) a cationic vinyl addition polymer prepared by polymerizing one or more ethylenically unsaturated monomers comprising a cationic monomer; (ii) an anionic polymer having one or more aromatic groups selected from the group consisting of polymers obtained by condensation of formaldehyde with benzene-based and naphthalene-based compounds, polyurethanes, polysaccharides, and lignin-based polymers; wherein (i) and (ii) are separately added to the suspension; and (iii) a low molecular weight cationic organic polymer having a molecular weight in the range of from 2,000 to about 700,000; or an anionic microparticulate material; and forming and draining the obtained suspension on a wire.
    Type: Grant
    Filed: June 10, 2005
    Date of Patent: February 10, 2009
    Assignee: Akzo Nobel N.V.
    Inventors: Sten Frölich, Fredrik Solhage, Erik Lindgren, Hans E. Johansson-Vestin
  • Process for sizing paper
    Patent number: 7318881
    Abstract: A process for sizing paper comprising adding to an aqueous suspension containing cellulosic fibers, and optional fillers, a sizing dispersion comprising a polymer having an aromatic group, and a sizing promoter comprising a polymer having an aromatic group, wherein the sizing dispersion and the sizing promoter are added separately to the aqueous suspension.
    Type: Grant
    Filed: May 10, 2004
    Date of Patent: January 15, 2008
    Assignee: Akzo Nobel N.V.
    Inventors: Erik Lindgren, Sten Frölich, Michael Persson, Barbro Magnusson
  • Process for the production of paper
    Patent number: 6918995
    Abstract: The invention relates to a process for the production of paper from an aqueous suspension containing cellulosic fibers, and optional fillers, which comprises separately adding to the suspension a cationic organic polymer having one or more aromatic groups and an anionic polymer having one or more aromatic groups, the anionic polymer being selected from step-growth polymers, polysaccharides and naturally occurring aromatic polymers and modifications thereof, forming and draining the suspension on a wire, with the proviso that if the anionic polymer is a step-growth polymer it is not an anionic melamine-sulphonic acid condensation polymer.
    Type: Grant
    Filed: August 6, 2001
    Date of Patent: July 19, 2005
    Assignee: Akzo Nobel N.V.
    Inventors: Sten Frölich, Fredrik Solhage, Erik Lindgren, Hans E. Johansson-Vestin
  • Process for sizing paper
    Patent number: 6846384
    Abstract: A process for sizing paper comprising adding to an aqueous suspension containing cellulosic fibers, and optional fillers, an anionic or cationic sizing dispersion, and a sizing promoter comprising a cationic organic polymer having an aromatic group; and an anionic polymer having an aromatic group selected from step-growth polymers, polysaccharides and naturally occurring aromatic polymers, wherein the sizing dispersion and sizing promoter are added separately to the aqueous suspension.
    Type: Grant
    Filed: August 6, 2001
    Date of Patent: January 25, 2005
    Assignee: Akzo Nobel N.V.
    Inventors: Erik Lindgren, Sten Frölich, Michael Persson
  • Process for sizing paper
    Patent number: 6818100
    Abstract: A process for sizing paper comprising adding to an aqueous suspension containing cellulosic fibres, and optional fillers, a sizing dispersion comprising a polymer having an aromatic group, and a sizing promoter comprising a polymer having an aromatic group, wherein the sizing dispersion and the sizing promoter are added separately to the aqueous suspension.
    Type: Grant
    Filed: August 6, 2001
    Date of Patent: November 16, 2004
    Assignee: Akzo Nobel N.V.
    Inventors: Erik Lindgren, Sten Frölich, Michael Persson, Barbro Magnusson
  • Sizing composition
    Patent number: 6485555
    Abstract: The present invention relates to sizing of paper and more specifically to a substantially water-free and aqueous composition of a sizing agent where the composition contains a cellulose reactive sizing agent, a cationic compound with a molecular weight up to 10000 and a non-ionic compound. Additionally, the invention relates to the preparation and use of above-mentioned compositions.
    Type: Grant
    Filed: December 21, 2001
    Date of Patent: November 26, 2002
    Assignee: Akzo Nobel N.V.
    Inventors: Erik Lindgren, Sten Frölich, Rein Sikkar
  • Sizing of paper
    Patent number: 6306255
    Abstract: The invention relates to an aqueous disperion containing a cellulose-reactive sizing agent and an anionic hydrophobicailly modified cellulose-derivative, its preparation and use in the production of paper. The invention also relates to a substantially water-free composition containing a cellulose-reactive sizing agent and an anionic hydrophobicailly modified cellulose-derivative, its preparation and use in the preparation of an aqueous dispersion of cellulose-reactive sizing agent. The invention further relates to a process for sizing cellulosic fibers by addition of an aqueous sizing dispersion containing a cellulose-reactive sizing agent and a hydroically modified dispersing agent to a stock containing cellulosic fibers, and optional fillers, and dewatering the stock on a wire to obtain a web containing cellulosic fibers.
    Type: Grant
    Filed: May 15, 2000
    Date of Patent: October 23, 2001
    Assignee: Akzo Nobel NV
    Inventors: Sten Frölich, Erik Lindgren, Rein Sikkar