Use of fine fibre cellulose for reinforcing paper

In various production processes, for example, in the production of disposable absorbent underwear, a large amount of fine fibre cellulose results as a by-product. Our objective was to obtain from it nanocellulose gels for using them in papermaking for reinforcing paper. Fine fibre cellulose nanoparticle gels were obtained by the thermocatalytic destruction method developed at the Laboratory of Cellulose of the Latvian State Institute of Wood Chemistry, followed by their dispersion, at the concentration of 8%, in water medium in a ball mill. A part of the obtained gels was used as filler in paper sheets produced from bleached softwood kraft pulp. The other part was used for obtaining coatings, which were cast on both sides of paper sheets produced from recycled paper by the Ligatne Paper Mill (Latvia). The investigations have shown that nanocellulose fillers improve the air resistance and mechanical properties of paper sheets. The coatings considerably increase the air resistance of paper sheets, although they decrease the tensile index in dry and wet states.