PAPER OR CARDBOARD ARTICLE HAVING AT LEAST ONE LAYER CONTAINING HIGH-YIELD CELLULOSE AND A METHOD FOR PRODUCTION THEREOF Russian patent published in 2021 - IPC D21H11/02 D21H11/08 D21H11/10 D21F3/00 D21F5/00 

FIELD: pulp industry.

SUBSTANCE: invention relates to production of paper or cardboard articles having at least one layer containing high output cellulose. Method involves providing a composition containing at least 50 wt % high output cellulose of total cellulose content, said high output cellulose being obtained when the wood is more than 85 %. Further, the composition is dewatered to produce a wet cloth, said wet web is pressed and dried to achieve a dry solid content of at least 50–70 wt %. Wet web is densified to a density of more than 600 kg/m³ in the pressing zone of the paper machine at a temperature above the softening temperature of saturated lignin contained in said high output cellulose, to produce paper or cardboard product containing at least 30 wt % of high output cellulose from total content of cellulose in said product. Then the web is dried till final drying.

EFFECT: reduced power consumption when making paper or cardboard products, as well as high strength in dry and wet conditions, compression strength and tensile strength of obtained articles.

15 cl, 10 dwg, 1 ex