| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing a combination paper, in the method for producing the combination paper of two or more layers comprising a process for combining wet paper layers after paper layer formation, pressing the combined layers and drying the combined layers, when an interlaminar strength is improved by adding a paper strengthening agent to a raw material for paper making before paper making and coating or spraying the surface of the wet paper layers before combination with an interlaminar adhesive, the interlaminar strength is sufficiently improved, tensile strength and fracture strength of paper sheet itself can be improved by completely reacting the paper strengthening agent the previous step with the interlaminar adhesive at the subsequent step. SOLUTION: The surface of the wet paper layers containing an amphoteric paper strengthening agent before the combination is sprayed with a dispersion liquid composed of an anionic water-soluble polymer fine particle having <=100μm particle diameter produced by subjecting a monomer consisting essentially of (meth)acrylic acid in the presence of a dispersant composed of an ionic polymer to dispersion polymerization to give the combination paper.
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