POLY(VINYL ALCOHOL)-BASED MULTIFUNCTIONAL BINDER FOR FINELY GROUND CALCIUM CARBONATE-BASED PIGMENT Russian patent published in 2004 - IPC

FIELD: paper-and-pulp industry.

SUBSTANCE: invention relates to process for preparing composition used in paper industry for applying surface coatings onto paper. Process is realized by mixing particles of poly(vinyl alcohol) powder with aqueous pigment dispersion, preferably finely ground calcium carbonate with average specific surface at least 50 m²/g until poly(vinyl alcohol) dissolves to form dispersion of pigment particles in aqueous poly(vinyl alcohol) solution with content of solids between 10 to 59%, dispersion containing 0.1 to 50 wt parts of dissolved poly(vinyl alcohol) per 100 wt parts pigment particles. Poly(vinyl alcohol) is characterized by degree of polymerization between 50 and 600 and it is hydrolyzed to 85-90 mol %. Poly(vinyl alcohol) particles have average size 200 mcm or less. Optionally, other additives can be mixed with dispersion of pigment particles in aqueous poly(vinyl alcohol) solution. Poly(vinyl alcohol) particles interact with pigment to lower Brookfield viscosity of pigment dispersions. Suspension can further be combined with other components thereby giving composition for containing paper for jet printers, which, when applied on paper, provides excellent appropriateness of the paper for jet printing.

EFFECT: widened choice of chemicals improving quality of printing paper.

18 cl, 4 tbl, 4 ex