To provide a method for enhancing both strength and durability of a fibrous sheet without adding an increased amount of starch, and a fibrous sheet which is insensitive to slack under a high humidity load and does not require a long drying time during a treatment.
The fibrous sheet is manufactured by a process comprising the following steps: a step of forming a fibrous slurry; a step of mixing with the fibrous slurry a resin mixture comprising a polyamideamine/epihalohydrin resin and a polymer, having a recurring unit derived from an alkyl halide bearing at least one double bond and an alkene, to form a wet strength mixture; a step of mixing an anionic polymer with the wet strength mixture to form a flocculated mixture; a step of forming the flocculated mixture into a fibrous sheet; and a step of drying the fibrous sheet to give the objective fibrous sheet.
HIMMELBERGER KARL B
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