The invention relates to an optical brightener for whitening and brightening of paper, board, textiles and non-wovens, a process for manufacturing said optical brightener, the use of said brightener in paper making processes and a process for whitening paper.

A method for producing a modified lignocellulosic pulp having improved wet-strength properties and a modified lignocellulosic pulp obtainable by the method.

Some variations provide a process for producing a nanocellulose material, comprising: providing a biomass feedstock comprising a bleached or unbleached pulp material; fractionating the feedstock in the presence of an acid, a solvent for lignin, and water, to generate cellulose-rich solids and a liquid containing hemicellulose and lignin; and mechanically treating the cellulose-rich solids to form cellulose fibrils and/or cellulose crystals, thereby generating a nanocellulose material. The process is preferably co-located with, or adjacent to, a mill that generates the pulp material. There are several advantages of a bolt-on AVAP® nanocellulose plant to an existing pulp mill, as disclosed herein.

Treatment methods for reduction of (1.fwdarw.3)-β-D-glucan leachables from cellulose-containing filter materials are described.

A super strong and tough densified wood structure is formed by subjecting a cellulose-based natural wood material to a chemical treatment that partially removes lignin therefrom. The treated wood retains lumina of the natural wood, with cellulose nanofibers of cell walls being aligned. The treated wood is then pressed in a direction crossing the direction in which the lumina extend, such that the lumina collapse and any residual fluid within the wood is removed. As a result, the cell walls become entangled and hydrogen bonds are formed between adjacent cellulose nanofibers, thereby improving the strength and toughness of the wood among other mechanical properties. By further modifying, manipulating, or machining the densified wood, it can be adapted to various applications.

Bleached polycrylic acid crosslinked cellulose fibers with reduced furfural content are disclosed. The reduced furfural content is accompanied by a strong reduction of malodor associated with crosslinked fibers. Methods of furfural reduction include treatment with hydrogen peroxide in the absence of alkaline or other bleaching agents subsequent to curing polyacrylic acid crosslinked cellulose fibers. Some embodiments of treated polycrylic acid crosslinked cellulose fibers have a furfural content lower than 1.3 ppm. In some embodiments, the reduction of furfural content of the treated crosslinked fibers compared to untreated crosslinked fibers is at least 55%. in some embodiments, furfural content decreases with aging of the treated crosslinked fibers.

Pulps in accordance with certain embodiments include crosslinked cellulose fibers and have high brightness, reactivity, and intrinsic viscosity, and therefore can be well suited for use as a precursor in the production of low-color, high-viscosity cellulose derivatives. A method in accordance with the present technology includes forming a pulp from a cellulosic feedstock, bleaching the pulp, crosslinking cellulose fibers within the pulp while the pulp has a high consistency, and drying the pulp. Crosslinking the cellulose fibers can include exposing the fibers to a glycidyl ether crosslinker having two or more glycidyl groups and a molecular weight per epoxide within a range from 140 to 175. Another method in accordance with the present technology includes providing an aqueous suspension of pulp that includes chemical wood pulp fibers that were previously bleached and dried, crosslinking the fibers with such a glycidal ether crosslinker, and drying the pulp.

A process for producing surface modified bleached chemical pulp fiber comprising fluidizing the bleached chemical pulp fiber and contacting the fluidized bleached chemical pulp fiber with an aerosol of a surface modifying composition comprising a surface modifying compound

It is an object of the present invention to optimize a bleaching process in a step of producing phosphorylated cellulose fibers. The present invention relates to a pulp comprising cellulose fibers having 0.5 mmol/g or more of phosphoric acid groups or phosphoric acid group-derived substituents, wherein when the pulp is processed into a sheet and four sheets are laminated on one another, the ISO whiteness of the laminate is 82% or more. Moreover, when the pulp of the present invention is processed into a sheet and four sheets are then laminated on one another, the b* value of the obtained laminate according to the L*a*b* color system is 5.5 or less.

The present invention is directed to fluff pulp having a Kappa number in the range of from 5 to 18 and having, when in the form of a dry sheet, ISO brightness in the range of from 30 to 60% and having a specific volume in the dry defibrated state of at least 19 dm3/kg and having absorption time in the range of from 2 to 4 seconds.