The present invention relates to a high-strength fibre composition comprising fibres up to 7 mm long with a viscosity of between 10 and 20 cP. The fibres present in said composition are distributed according to the length thereof, thereby guaranteeing high strength. The fibre composition according to the invention can also be redispersible. The use of the fibre composition according to the invention and an article comprising said composition are also disclosed.

A dispersion of cellulose fibers, a method of preparing the same and uses thereof. The dispersion is produced by providing a cellulose feedstock comprising cellulose fibers; by providing a mixture of an ionic liquid and a protic antisolvent for cellulose as a dispersion medium, the ionic liquid being selected from the group of protic salts of superbases capable of dissolving cellulose; and by mixing said cellulose feedstock into said dispersion medium so as to disperse the cellulose fibers therein to form a dispersion which is stable for at least 24 hours at room temperature. The dispersion can be used as an additive of cellulose pulps for making of fibrous products.

A dispersion of cellulose fibers, a method of preparing the same and uses thereof. The dispersion is produced by providing a cellulose feedstock comprising cellulose fibers; by providing a mixture of an ionic liquid and a protic antisolvent for cellulose as a dispersion medium, the ionic liquid being selected from the group of protic salts of superbases capable of dissolving cellulose; and by mixing said cellulose feedstock into said dispersion medium so as to disperse the cellulose fibers therein to form a dispersion which is stable for at least 24 hours at room temperature. The dispersion can be used as an additive of cellulose pulps for making of fibrous products.

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.

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 paper product can comprise making one or more sheets at least by, for each of the sheet(s), forming a web from one or more furnishes that comprise fibers dispersed in water. The fibers of the furnish(es) can comprise a plurality of first fibers that are hardwood fibers and a plurality of second fibers that include softwood fibers and surface enhanced pulp fibers (SEPF), the SEPF having a length weighted average fiber length of at least 0.20 mm. The method can comprise at least partially dewatering the web to form the sheet. The sheet(s) can be laminated and/or embossed such that a total dry tensile strength of the paper product is less than or equal to 90% of the sum of the total dry tensile strength(s) of the sheet(s).

A method of making a paper product can comprise making one or more sheets at least by, for each of the sheet(s), forming a web from one or more furnishes that comprise fibers dispersed in water. The fibers of the furnish(es) can comprise a plurality of first fibers that are hardwood fibers and a plurality of second fibers that include softwood fibers and surface enhanced pulp fibers (SEPF), the SEPF having a length weighted average fiber length of at least 0.20 mm. The method can comprise at least partially dewatering the web to form the sheet. The sheet(s) can be laminated and/or embossed such that a total dry tensile strength of the paper product is less than or equal to 90% of the sum of the total dry tensile strength(s) of the sheet(s).

A method of producing chemical pulp including at least the following steps: a) wood chips or other comminuted ligno-cellulosic fibrous material is treated with a polysulfide-containing cooking liquor in an impregnation stage at a temperature of 90-145° C., and b) slurry of fibrous material from step a) is heated into cooking temperature and cooked for producing pulp having a desired kappa number. After step a) mercaptide ions are added into the slurry of fibrous material and the fibrous material is treated at cooking temperature in step b).

A method of producing chemical pulp including at least the following steps: a) wood chips or other comminuted ligno-cellulosic fibrous material is treated with a polysulfide-containing cooking liquor in an impregnation stage at a temperature of 90-145° C., and b) slurry of fibrous material from step a) is heated into cooking temperature and cooked for producing pulp having a desired kappa number. After step a) mercaptide ions are added into the slurry of fibrous material and the fibrous material is treated at cooking temperature in step b).

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.