The invention relates to a method for producing particles of mineral material comprising grinding of at least one mineral material in the presence of water. The grinding according to the invention is carried out in the presence of at least one polymer obtained by a radical polymerization reaction of a partial sodium salt of itaconic acid and partial decarboxylation of the polymer obtained followed by partial or total neutralization of the decarboxylated polymer. The invention also relates to an aqueous composition comprising particles of ground mineral material and such a polymer, in particular a mass-loading composition for the production of paper or a paper-coating-colour composition.

The invention relates to a method for producing particles of mineral material comprising grinding of at least one mineral material in the presence of water. The grinding according to the invention is carried out in the presence of at least one polymer obtained by a radical polymerization reaction of a partial sodium salt of itaconic acid and partial decarboxylation of the polymer obtained followed by partial or total neutralization of the decarboxylated polymer. The invention also relates to an aqueous composition comprising particles of ground mineral material and such a polymer, in particular a mass-loading composition for the production of paper or a paper-coating-colour composition.

The present invention relates to a refined cellulose fiber composition useful as a strength enhancing agent for paper and paperboard, wherein the refined cellulose fiber composition has a Schopper-Riegler (SR) number in the range of 80-98 as determined by standard ISO 5267-1, and wherein the refined cellulose fiber composition has a content of fibers having a length >0.2 mm of at least 12 million fibers per gram based on dry weight. The invention further relates to a method for preparing the refined cellulose fiber composition and to pulp paper and paperboard comprising the refined cellulose fiber composition.

A method of making a market pulp can include separating a slurry comprising a plurality of pulp fibers into at least first and second pulp feeds. The first pulp feed can be refined at least by, for each of one or more mechanical refiners, introducing the first pulp feed between two refining elements of the refiner and rotating at least one of the refining elements, each of the refining elements comprising a plurality of bars and a plurality of grooves, where a width of each of the bars is less than or equal to 1.3 mm and a width of each of the grooves is less than or equal to 2.5 mm. The refiner(s) can consume at least 300 kWh per ton of fiber. The refined first pulp feed and second pulp feed, which is not refined, can be combined to produce a third pulp feed that can be dried.

The present invention refers to the separation of cellulose pulp into distinct fractions with different draining and morphological characteristics, as well as the use of part of these fractions for the production of nanocellulose. The process in reference combines the unitary operations of fiber separation, thickening to a certain consistency, draining and drying of the cellulosic pulp with the high drainage ability and production of nanocellulose from high primary fines content pulp. The process may consider any cellulosic pulp fiber derived from short or long fiber woods such as Eucalyptus, Corymbia, Birch, Aspen, Pinus, recycled fibers, etc., their residues such as bark, sawdust, etc.

A fiber blend includes a first amount of wood pulp fibers refined in an amount of at least about 150 kWh per metric ton of gross refining energy, and a second amount of wood pulp fibers refined in an amount of at most about 10 kWh per metric ton of gross refining energy.

A process for manufacturing a web material is disclosed. The process generally provides the steps of: a. providing a pulp material comprising fibers and vessels; b. separating said vessels from said fibers in said pulp material to form a slurry having at least about 7 percent less vessels per meter than said pulp material; and c. processing said slurry to form said web material.

A process for improving high aspect ratio cellulose filament blends comprising the steps of: a) providing a blend of cellulose nano-filaments or blend of cellulose micro-filaments; b) diluting the blend of cellulose nano-filaments or the blend of cellulose micro-filaments to a target consistency; c) fractionating the diluted blend of cellulose nano-filaments or the diluted blend of cellulose micro-filaments from the step c); and, d) collecting the fraction of the diluted blend of cellulose nano-filaments or the diluted blend of cellulose micro-filaments from the step c) having an average length of greater than at least about 25 μm.

A system for treating recycled cellulosic fibers to improve paper, board and tissue quality; the system involves fractionating recycled fibers into a short fiber portion and a long fiber portion. The short fiber portion is split into an original short fiber portion and a refinable portion. The refinable portion is processed into glue pulp. The glue pulp is refined to targeted, measured fiber properties. Varying amounts of the glue pulp, original short unrefined fibers, and long unrefined fibers are blended together to form an optimized slurry that is processed by a paper machine into an optimized recycled paper product. The process provides for improved drainage with the same or better paper properties allowing for cost reductions in fabrication.

A process for manufacturing a web material is disclosed. The process generally provides the steps of: a. providing a pulp material comprising fibers and vessels; b. separating said vessels from said fibers to form an accepts stream and a rejects stream; c. forming plies with the rejects and accepts streams; and d. joining the plies.