Fpinnovations

Pulp and Paper Research Institute of Canada

Jarka Matous

Peter Volf

Makhlouf Laleg

Jan Martin Strmen

Miroslav Antal

Ivan I. Pikulik

Xujun Hua

Ivan I Pikulik

Lahoucine Ettaleb

Danielle Gagne

Steven Middleton

Roderick Collins

Michael Paleologou

Naceur Jemaa

Gilles Marcel Dorris

Yaolin Zhang

Keith Miles

Xuejun Zou

Reza Amiri

Joseph Stephen Aspler

Tony Manfred

Joelle Grenon

Tom Owston

Michael Stacey

Thomas Owston

Waleed Wafa Al Dajani

The present invention is directed to a method of transforming a pulp fibrous into a pre-dispersed semi-dry or dry fibrous material and to the material produced. The method opens, de-entangles and fibrillates the fibrous material of the input pulp. The method mixes the input fibrous with chemicals while evaporating moisture in an updated mechanical disc refiner process. The refiner operates to set three process variables: 1) applied refining specific energy; 2) refiner gap opening and 3) refiner output consistency. Depending on the feed pulp type and consistency, the refiner's output is a pre-dispersed semi-dry fibrous material of 30 to 99% solids with 70 to 100% of separated fibers that depending on chemical treatment are loosely entangled fibrous that disperse in water using common techniques. The pre-dispersed semi-dry output may be further processed inline or by batch process air agitation at velocities sufficient to further separate fibers and loosen fibrous entanglements.

Method of transforming high consistency pulp fibers into pre-dispersed semi-dry and dry fibrous materials

The present invention relates to the use of cellulose nanocrystals (CNC) blended with a polymeric material selected from a polyvinyl alcohol) (PVOH), an ethylene acrylic acid copolymer (EAA), other carboxylated polymer latexes, or other polymer blends, and applied as a thin coating layer on plastic films for printing with digital processes such as inkjet and laser printing, as well as with more conventional printing processes such as flexography and offset lithography, to the control of ink adhesion to the plastic film, and to the reduction in the oxygen transmission rate (OTR) of the plastic film.

Print quality on thin coatings of cellulose nanocrystals

Cellulose nanofilaments from cellulose fibers, a method and a device to produce them are disclosed. The nanofilaments are fine filaments with widths in the sub-micron range and lengths up to a couple of millimeters. These nanofilaments are made from natural fibers from wood and other plants. The surface of the nanofilaments can be modified to carry anionic, cationic, polar, hydrophobic or other functional groups. Addition of these nanofilaments to papermaking furnishes substantially improves the wet-web strength and dry sheet strength much better than existing natural and synthetic polymers. The cellulose nanofilaments produced by the present invention are excellent additives for reinforcement of paper and paperboard products and composite materials, and can be used to produce superabsorbent materials.

Cellulose nanofilaments and method to produce same

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.

High aspect ratio cellulose nanofilaments and method for their production

A method to prepare aqueous furnishes useful as feedstock in the manufacture of very high-mineral content products, particularly paper sheets having mineral filler content up to 90% that display the required physical properties for the intended applications; the furnishes comprise fibrillated long fibers/mineral fillers mixed with anionic acrylic binders and co-additives, in presence or absence of cellulose fibrils; the fibrillated long fibers and cellulose fibrils provide high surface area for greater filler fixation and the reinforcement backbone network that ties all of the product components together; the anionic binders allow rapid and strong fixation of filler particles onto the surfaces of fibrils when mixing is conducted at temperatures higher than the glass transition temperature (T) of the binder. The aqueous furnish provides excellent filler retention and drainage during product fabrication.

Cellulose-reinforced high mineral content products and methods of making the same

A filler treatment process enhances the fixation of anionic latex on filler in a short time. Anionic polymer dispersions (latex) are added to papermaking filler slurries at ambient temperature and then mixed with water of temperature higher than the glass transition temperature (T) of the latex used. The anionic latexes applied by this process are totally and irreversibly fixed or bound onto the filler particles and the treated filler particle agglomerate to form an aggregated filler slurry which is stable over time. The latex-treated filler slurry can be added to papermaking furnishes at any point prior to the headbox of the paper machine or stored for later use. The latex-treated filler slurry improves filler retention, only slightly reduces sheet strength and improves sizing performance.

Latex-treated filler slurries for use in papermaking

A novel filler treatment comprising the preparation of swollen starch compositions, prepared in the presence or absence of co-additives, and the addition of the said composition to a filler suspension, has been developed. Use of the treated filler during papermaking improves filler retention and produces filled papers where addition of the filler has only a minimal negative effect on strength properties. The swollen starch compositions can be prepared in a batch or jet cooker, or by mixing with hot water under controlled conditions (i.e., temperature, pH, mixing, mixing time) in order to make the starch granules swell sufficiently to improve their properties as a filler additive but avoiding excess swelling leading to their rupture. The swollen starch composition is then rapidly mixed with the filler slurry, preferably in a static mixer, and added to the papermaking furnish at a point prior to the headbox of the paper machine.

Unruptured, ionic, swollen starch for use in papermaking

A continuous fiIter treatment process in which anionic polymer dispersions (latex) are added to common papermaking filler slurries ai ambient temperature and then mixed with water of temperature higher than the glass transition temperature (Tg) of the latex used. To efficiently fix the latex the temperature of the filler/latex mixture must be 30-60&#xb0; C. higher than ihe Tg of the latex used. The chemical composition of the resin and the type of surfactant used during the emulsion polymerization process of the polymer latex dispersions are important factors for efficiently fixing the latex onto the filler by adding hot water and improving the properties of paper made with the treated filler. Enhanced fixation of anionic latex onto filler using hot water is done in mixing vessels that can control shear and mixing time. The anionic latexes are totally and irreversibly fixed or bound onto the filler particles and the aggregated filler slurry is stable over time. The latex-treated filler slurry can be added to papermaking furnishes at any point prior to the headbox of the paper machine or stored for later use. It can be added to wood-free or wood-containing furnishes commonly used for making fine papers, mechanical pulp papers, and multi-ply paperboards. Filler retention with only slightly reduce sheot strength and sizing performance are improved. Treated calcium carbonate filler is more acid-resistant and, when used in manufacturing mechanical pulp paper under neutral conditions, less acid is needed to control the pH.

A new class of polymeric additives for papermaking is disclosed as well as a process for their manufacture, a method for their use and a paper sheet containing the addition. The additives can be used in paper manufacture as agents for improving retention, paper machine operation and the strength properties of the product. The additives are manufactured from a microbial biomass. The biomass that contains acetyl amino groups or other amides is chemically modified by hydrolysis of the amides to form primary amino groups. Under neutral or acidic conditions these primary amines become cationic, which assures a good absorption of the additive onto fibres and fines of pulp that is generally of anionic nature.

Papermaking additive

A novel filler treatment comprising the preparation of swollen starch-latex compositions, prepared in the presence or absence of co-additives, and the addition of the said composition to a filler suspension, has been developed. Use of the treated filler during papermaking improves filler retention and produces filled papers where addition of the filler has only a minimal negative effect on strength properties. The swollen starch-latex compositions can be prepared in a batch or jet cooker, or by mixing with hot water under controlled conditions (i.e., temperature, pH, mixing, mixing time) in order to make the starch granules swell sufficiently to improve their properties as a filler additive but avoiding excess swelling leading to their rupture. The swollen starch-latex composition is then rapidly mixed with the filler slurry, preferably in a static mixer, and added to the papermaking furnish at a point prior to the headbox of the paper machine. The starch-latex composition can be used with wood-free or wood-containing furnishes. The treated filler is easily retained in the web during papermaking, improves drainage, and gives sheets having good formation. Sheets made with the treated fillers have higher bonding and tensile strengths than sheets produced using filler treated with either swollen starch alone or latex alone. Retention and drainage are further improved when conventional retention aid chemicals are added to the furnish containing the treated filler. The use of swollen starch-latex compositions could allow the papermaker to increase the filler content of the paper without sacrificing dry strength properties or increasing the amount, and hence the cost, of the retention aid added. The combination of swollen starch and latex could be used as furnish additives in the manufacture of both filled grades and grades that contain no filler such as sack papers and paperboard products.

Swollen starch-latex compositions for use in papermaking

A method is disclosed for reducing or inhibiting alkaline darkening of mechanical pulp caused by the presence of calcium carbonate filler during production; the method comprises adding a sulfite, or sulfur-containing reducing agent, especially a sulfite to the mechanical pulp and the filler; the method is usefully applied in the production of mechanical pulp and paper in which calcium carbonate is used as a filler and also in the production of paper at neutral or mildly alkaline conditions.

Method for reducing alkaline darkening of mechanical pulp containing a calcium carbonate filler

A graft polymer comprises a carbohydrate polymer having pendant 3-amino-2-hydroxy propyl groups grafted thereon and may be employed as a retention aid and strengthening additive in paper manufacture. When the carbohydrate polymer is a component of wood pulp the resulting chemically modified wood pulp may be employed in conjunction with unmodified wood pulp to incorporate therein the retention and strengthening characteristics.

Growing community of inventors

Pointe-Claire, Canada

Makhlouf Laleg