INTERLAMINAR STRENGTH-IMPROVING AGENT AND INTERLAMINAR STRENGTH-IMPROVING METHOD

摘要

PROBLEM TO BE SOLVED: To provide an interlaminar strength-improving agent which is used on the production of combination paper, has a particle size that is larger than the particle size of a polyion complex or emulsion and is approximately the same as the particle size of starch, does therefore not flow out together with water in a dehydration press part or a suction part, and consequently exhibits the same interlaminar strength in the amount of one-fifth to one-tenth of starch. SOLUTION: This interlaminar strength-improving agent comprises <=100μm inorganic particle-containing ionic polymer fine particles obtained by dispersing and copolymerizing an ionic water-soluble monomer and a copolymerizable monomer in the presence of inorganic particles and in the coexistence of a polymer dispersant soluble in a salt aqueous solution in the salt aqueous solution with stirring.