Abstract: The present description relates to a process of producing a dry mixed product comprising cellulose filament (CF) and a carrier fiber, and a dry mixed product of re-dispersible cellulose filament and a carrier fiber that permits the CF to retain its dispersibility in water and hence superior reinforcement ability in papermaking furnishes, composite materials, or other materials where CF is used. The process comprises mixing a water suspension of never-dried CF with a cellulose fiber pulp carrier followed by thickening to a suitable concentration so that it can be further processed and dried in a conventional device such as a dryer can of a pulp machine or a flash dryer.

Abstract: The present disclosure relates to filter media comprising base filter fibers and cellulose filaments. For example, cellulose filaments can increase at least one mechanical property of the filter media as compared to filter media prepared from the base filter fibers alone. The disclosure also relates to various processes for preparing a filter medium, processes for increasing filtration efficiency of a filter medium, processes for increasing a minimum efficiency reporting value (MERV) rating of a filter medium.

Abstract: There are provided gypsum panels, sheets and multi-layer sheets as well as methods of preparation thereof. For example, there are provided cellulose filament-reinforced gypsum panels, sheets and multi-layer sheets and methods of preparation thereof. For example, in such gypsum panels, sheets and multi-layer sheets gypsum is bound with cellulose filaments to strengthen the gypsum panels, sheets and multi-layer sheets. The cellulose filament-reinforced gypsum panel can be, for example, a core comprising a honeycomb or corrugated structure. There are also provided aqueous suspensions comprising cellulose filaments and CaSO4.2H2O.

Abstract: The present disclosure relates to composite materials comprising a resin and at least one sheet that comprise optionally cellulose filaments (CF), fillers and optionally reinforcing fibers as well as methods for the preparation thereof. The methods comprise impregnating the sheets comprising the cellulose filaments, fillers and optionally the reinforcing fibers or a stack thereof with resin. The composite materials can optionally comprise at least one other sheet, the at least one other sheet being different from the at least one sheet and comprising fibers chosen from wood pulp, fiberglass, natural fibers and mixtures thereof. The sheet can also be in the form of a panel of a preform.

Abstract: The present description relates to a process of producing a dry mixed product comprising cellulose filament (CF) and a carrier fibre, and a dry mixed product of re-dispersible cellulose filament and a carrier fibre that permits the CF to retain its dispersibility in water and hence superior reinforcement ability in papermaking furnishes, composite materials, or other materials where CF is used. The process comprises mixing a water suspension of never-dried CF with a cellulose fibre pulp carrier followed by thickening to a suitable concentration so that it can be further processed and dried in a conventional device such as a dryer can of a pulp machine or a flash dryer.

Abstract: There are provided gypsum panels, sheets and multi-layer sheets as well as methods of preparation thereof. For example, there are provided cellulose filament-reinforced gypsum panels, sheets and multi-layer sheets and methods of preparation thereof. For example, in such gypsum panels, sheets and multi-layer sheets gypsum is bound with cellulose filaments to strengthen the gypsum panels, sheets and multi-layer sheets. The cellulose filament-reinforced gypsum panel can be, for example, a core comprising a honeycomb or corrugated structure. There are also provided aqueous suspensions comprising cellulose filaments and CaSO4.2H2O.

Abstract: A method to produce on a commercial scale, high aspect ratio cellulose nanofilaments (CNF) from natural lignocellulosic fibers comprises a multi-pass high consistency refining (HCR) of chemical or mechanical fibers using combinations of refining intensity and specific energy. The CNF produced represents a mixture of fine filaments with widths in the submicron and lengths from tens of micrometers to few millimeters. The product has a population of free filaments and filaments bound to the fiber core from which they were produced. The proportion of free and bound filaments is governed in large part by total specific energy applied to the pulp in the refiner, and differs from other cellulose fibrillar materials by their higher aspect ratio and the preserved degree of polymerization (DP) of cellulose, and are excellent additives for the reinforcement of paper, tissue, paperboard and the like. They display exceptional strengthening power for never-dried paper webs.

Abstract: A method for the production of cellulose films with at least one hydrophobic or less hydrophilic surface, or with at least one surface with a water contact angle (?) in a range from 55° to less than 100° is described. The method involves contacting the cellulose material with a hydrophobic solid material during the preparation of the cellulose films or with a vapour of a non-polar or polar aprotic solvent during or after the preparation of the cellulose films. Examples of the cellulose material are cellulose filaments (CF) made to have at least 50% by weight of the filaments having a filament length up to 350 ?m and a filament diameter between 100 and 500 nm from multi-pass, high consistency refining of wood or plant fibers, and commercially-available sodium carboxymethyl cellulose. Examples of the hydrophobic solid material are hydrophobic polymers, poly(methylpentene) and poly(ethylene). Examples of the non-polar solvent are hexane and toluene.

Abstract: A method to produce on a commercial scale, high aspect ratio cellulose nanofilaments (CNF) from natural lignocellulosic fibers comprises a multi-pass high consistency refining (HCR) of chemical or mechanical fibers using combinations of refining intensity and specific energy. The CNF produced represents a mixture of fine filaments with widths in the submicron and lengths from tens of micrometers to few millimeters. The product has a population of free filaments and filaments bound to the fiber core from which they were produced. The proportion of free and bound filaments is governed in large part by total specific energy applied to the pulp in the refiner, and differs from other cellulose fibrillar materials by their higher aspect ratio and the preserved degree of polymerization (DP) of cellulose, and are excellent additives for the reinforcement of paper, tissue, paperboard and the like. They display exceptional strengthening power for never-dried paper webs.

Abstract: Oxidized white liquor is heat treated to increase the concentration of polysulphide measured at 285 or 286 nm (PSUV) or measured at 416 nm (PSVIS) and the PSUV/PSGR or PSVIS/PSGR ratio, whereby the content of active polysulphide in the total polysulphide is increased which active polysulphide can be exploited to increase pulp yield in Kraft pulping.

Abstract: Sodium sulfide or hydrosulfide is oxidized to produce sodium polysulfide and sodium hydroxide. Under appropriate conditions, the oxidation may be pursued further to convert all the sodium sulfide into sodium thiosulfate. The oxidation is carried out at or above atmospheric pressure in a mixed reactor or in a pipeline reactor, by sparging oxygen or air, in a mixture of white liquor and lime mud particles produced in the recausticizing plant of a kraft mill.