초록 ▼

The fines retention or drainage properties of mechanical pulps in the paper making process are improved by including in the thin stock, not after the last point of high shear, particles of a water-dispersible colloid siliceous material such as a bentonite clay in intimate association with a low mole

The fines retention or drainage properties of mechanical pulps in the paper making process are improved by including in the thin stock, not after the last point of high shear, particles of a water-dispersible colloid siliceous material such as a bentonite clay in intimate association with a low molecular weight water soluble high anionic charge density polymer, such as polyacrylic acid having a molecular weight below 50,000 and a charge density of at least 4 m eq/g and further including in the thin stock, after the last point of high shear, a non-ionic high molecular weight polyelectrolyte such as polyacrylamide having a molecular weight of at least 100,000.

대표청구항 ▼

A process for the production of paper or paperboard from a mechanical stock comprising including in the thin stock in the papermaking process, not after the last point of high shear in the process, a particular water-dispersible colloidal siliceous material selected from the group consisting of clay

A process for the production of paper or paperboard from a mechanical stock comprising including in the thin stock in the papermaking process, not after the last point of high shear in the process, a particular water-dispersible colloidal siliceous material selected from the group consisting of clay minerals, synthetic analogues thereof and silica, the particles of the colloidal siliceous material being in intimate association with an electrophoretic mobility modifying quantity of a water soluble polymer having a molecular weight below 50,000 and an anionic charge density of from 4 to 24 meq/g and further including in the thin stock, after the last point of high shear in the process a flocculating quantity of a substantially non-ionic polyelectrolyte flocculent having a molecular weight of at least 100,000.