WATER IN OIL TYPE ACRYLAMIDE-BASED POLYMER EMULSION, YIELD-IMPROVING AGENT COMPOSITION FOR PAPER-MAKING, PAPER AND USE OF YIELD-IMPROVING AGENT

摘要

PROBLEM TO BE SOLVED: To obtain an yield-improving agent composition for a paper-making, capable of improving the yield of fine fibers and water-filtering property in a paper-making process by using a water in oil type emulsion of a specific acrylamide-based polymer. SOLUTION: This yield-improving agent composition for a paper-making is prepared by containing a water in oil type acrylamide-based polymer emulsion obtained by bringing a water in oil type acrylamide-based polymer emulsion consisting of a cationic acrylamide-based polymer having 1.0-3.1 meq/g cationic degree or an anionic acrylamide-based polymer having 0.7-3.9 meq anionic degree with a de-ionized water for making a phase reversion, and has at least 1,000 mPa.s salt viscosity of an aqueous solution of 1 wt.% effective concentration of the acrylamide-based polymer, at least 15 mm thread-forming length Ls1 and at least 0.80 ratio of the thread-forming length Ls2 of 0.1 wt.% aqueous solution of effective polymer concentration to the above thread-forming length Ls1, (Ls1/Ls2).