Akzo Nobel N.v.

Eka Chemicals Ab

Akzo Nobel Pulp and Performance Chemicals Ab

Sten Frölich

Erik Lindgren

Rein Sikkar

Michael Persson

Fredrik Solhage

Hans Erik Johansson-Vestin

Hans Hallstrom

Barbro Magnusson

Hans Johansson-Vestin

Kjell Andersson

Hans E Johansson-Vestin

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.

Process for production of paper

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.

Process for sizing paper

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. The invention further 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, forming and draining the suspension on a wire, with the proviso that the anionic polymer is not an anionic polystyrene sulphonate or anionic melamine-sulphonic acid condensation polymer.

Process for the production of paper

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.

The invention relates to an aqueous dispersion containing a dispersant and a disperse phase containing a hydrophobic material, the dispersant comprising an anionic compound having a molecular weight less than 50,000 and being selected from the group consisting of carbon-containing compounds and silicon-containing compounds, and a cationic organic compound having a molecular weight less than 50,000. The invention further relates to the preparation and use of the dispersion in the production of paper. The invention also relates to a substantially water-free composition containing a hydrophobic material, an anionic compound having a molecular weight less than 50,000 and being selected from carbon-containing compounds and silicon-containing compounds, and a cationic organic compound having a molecular weight less than 50,000, as well as it use in the preparation of an aqueous dispersion.

Aqueous dispersions of hydrophobic material

The invention relates to an aqueous dispersion containing a cellulose-reactive sizing agent and an anionic hydrophobically 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 hydrophobicity modified cellulose-derivative, its preparation and use in the preparation of an aqueous dispersion 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 hydrophobically 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.

Sizing of paper

The invention relates to an aqueous dispersion containing a cellulose-reactive sizing agent and a dispersant system comprising a low molecular weight cationic organic compound having a molecular weight less than 10,000 and an anionic stabilizer, its preparation and use in the production of paper. The invention further relates to a substantially water-free composition containing a cellulose-reactive sizing agent, a low molecular weight cationic organic compound having a molecular weight less than 10,000 and an anionic stabilizer, its preparation and use in the preparation of an aqueous dispersion of cellulose-reactive sizing agent.

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Askim, Sweden

Sten Frölich