A process is provided for making a fluff pulp sheet, comprising contacting at least one cationic trivalent metal, salt thereof, or combination thereof with a composition comprising fluff pulp fibers and water at a first pH, to form a fluff pulp mixture; forming a web from the fluff pulp mixture; and applying at least one debonder surfactant to the web and raising the pH to a second pH, which is higher than the first pH, to make the fluff pulp sheet. A fluff pulp sheet is also provided, comprising a web comprising fluff pulp fibers; at least one cationic trivalent metal, salt thereof, or combination thereof; at least one debonder surfactant; and a fiberization energy of <145 kJ/kg. Products and uses of the fluff pulp sheet are also provided.

A method for making a specialty fiber by activating pulp in an alkaline aqueous medium, then reacting it a water-soluble, multi-functional reagent able to bridge neighboring cellulose chain within a single fiber. The resultant specialty cellulose fibers have high intrinsic viscosity and may be used to make cellulose ethers, cellulose acetate, and viscose.

The present invention provides a pulp product (e.g., paper) comprising cellulose and nanocellulose, wherein the nanocellulose is derived from the cellulose in a mechanical and/or chemical step that is separate from the main pulping process. The pulping process may be thermomechanical pulping or hydrothermal-mechanical pulping, for example. The pulp product is stronger and smoother with the presence of the nanocellulose. The nanocellulose further can function as a retention aid, for a step of forming the pulp product (e.g., in a paper machine). Other embodiments provide a corrugated medium pulp composition comprising cellulose pulp and nanocellulose, wherein the nanocellulose includes cellulose nanofibrils and/or cellulose nanocrystals and the nanocellulose may be hydrophobic. The nanocellulose improves the strength properties of the corrugated medium. In some embodiments, the cellulose pulp is a GreenBox+® pulp and the nanocellulose is derived from the AVAP® process.

The present invention provides a pulp product (e.g., paper) comprising cellulose and nanocellulose, wherein the nanocellulose is derived from the cellulose in a mechanical and/or chemical step that is separate from the main pulping process. The pulping process may be thermomechanical pulping or hydrothermal-mechanical pulping, for example. The pulp product is stronger and smoother with the presence of the nanocellulose. The nanocellulose further can function as a retention aid, for a step of forming the pulp product (e.g., in a paper machine). Other embodiments provide a corrugated medium pulp composition comprising cellulose pulp and nanocellulose, wherein the nanocellulose includes cellulose nanofibrils and/or cellulose nanocrystals and the nanocellulose may be hydrophobic. The nanocellulose improves the strength properties of the corrugated medium. In some embodiments, the cellulose pulp is a GreenBox+® pulp and the nanocellulose is derived from the AVAP® process.

The present invention relates to cellular solid materials comprising cellulose nanofibers (CNF) and an anionic surfactant, a method for preparation of such materials, as well as their use.

A porous body is placed in a rectangular parallelepipedal casing made of a stainless steel to prepare a mold form. A CNF-containing slurry is charged into the mold form, and another porous body is placed on the CNF-containing slurry. If the CNF-containing slurry are enwrapped in a nylon mesh, leakage of the CNF-containing slurry from a gap between the mold form and the porous body or clogging of the porous bodies can be inhibited. The upper and lower porous bodies are heated while applying a load to the CNF-containing slurry for a desired period of time to effect hot pressing, thereby obtaining a desired molded product. This provides a method for molding CNFs which enables a CNF molded product having a three-dimensional configuration to be obtained at a high productivity, and the CNF molded product obtained by the method for molding CNFs.

In a method for preparing nanofibrillar cellulose, fibrous dispersion of ionically charged cellulose is repeatedly passed through a mechanical process of disrupting fibers into fibrils until the viscosity starts to decrease. The number average diameter of the nanofibrillar cellulose after the mechanical process is in the range of 2-10 nm, and the zero-shear viscosity is below 10 Pa.Math.s, preferably below 1 Pa.Math.s, when measured in the concentration of 0.5 wt-%. The nanofibrillated cellulose is low aspect ratio nanofibrillated cellulose (NFC-L).

In a method for preparing nanofibrillar cellulose, fibrous dispersion of ionically charged cellulose is repeatedly passed through a mechanical process of disrupting fibers into fibrils until the viscosity starts to decrease. The number average diameter of the nanofibrillar cellulose after the mechanical process is in the range of 2-10 nm, and the zero-shear viscosity is below 10 Pa.Math.s, preferably below 1 Pa.Math.s, when measured in the concentration of 0.5 wt-%. The nanofibrillated cellulose is low aspect ratio nanofibrillated cellulose (NFC-L).

A sheet having dead-fold properties, wherein said sheet comprises cellulose fibers whereof at least 75%, preferably at least 90%, or more preferably at least 95% of said cellulose fibers have a fiber length of less than 1 mm, and wherein the tensile strength ratio (MD/CD) of the film is above 1.4, preferably higher than 1.6 and most preferably higher than 1.8.

A sheet having dead-fold properties, wherein said sheet comprises cellulose fibers whereof at least 75%, preferably at least 90%, or more preferably at least 95% of said cellulose fibers have a fiber length of less than 1 mm, and wherein the tensile strength ratio (MD/CD) of the film is above 1.4, preferably higher than 1.6 and most preferably higher than 1.8.