CROSSLINKED WATER-SOLUBLE POLYMER DISPERSION LIQUID AND PAPER MAKING METHOD USING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a method for efficiently producing a crosslinked water-soluble polymer in a state of stable dispersion liquid to improve the aggregation function of a cationic or amphoteric water-soluble polymer by the dispersion polymerization in an aqueous solution of a salt in the presence of a polymer dispersing agent soluble in the salt solution and to develop a paper making method to use the crosslinked water-soluble polymer. SOLUTION: The crosslinked water-soluble polymer having a turbidity of 5-200 FAU (measured by visible light of 850 nm wavelength) measured by diluting the polymer with water to a polymer concentration of 0.5 wt.% and determining with a spectrophotometer is produced in high efficiency in a stably dispersed liquid state by a dispersion polymerization of a water-soluble monomer (mixture) composed of a cationic water-soluble monomer and optionally an anionic monomer, (meth)acrylamide and other copolymerizable nonionic water-soluble monomer in an aqueous solution of a salt in the presence of a polymer dispersing agent soluble in the salt solution. The addition of the crosslinked water-soluble polymer dispersion liquid to a paper-making raw materials before the paper making process improves the yield and/or freeness and gives a paper sheet having good formation. COPYRIGHT: (C)2006,JPO&NCIPI