METHOD FOR PRODUCING PAPERBOARD

摘要

PROBLEM TO BE SOLVED: To provide a method for producing combination paper by which both a sufficient improvement in ply bond strength and an improvement in strength (internal strength) in the Z direction of a paper sheet itself are achieved without increasing chemical cost when the surface of a wet paper web ply before combination is coated or sprayed with a ply adhesive to improve the ply bond strength in the method for producing the >=2-ply combination paper comprising steps of combining each wet paper web ply after forming the paper ply, then pressing the combined ply and further drying the pressed ply. SOLUTION: This method for producing a paperboard comprises spray-adding a mixture dispersion containing anionic water-soluble polymer fine particles produced by dispersing and polymerizing monomers consisting essentially of (meth)acylic acid in the coexistence of a dispersing agent composed of an ionic polymer in an aqueous solution of a salt and having <=100μm particle diameter and starch particles before gelatinization to the surface of the wet paper web ply before combination.