Copolymer, paper-treating agent, and processed paper

摘要

A paper treatment agent which contains a copolymer essentially comprising a repeating unit derived from a polyfluoroalkyl group-containing (meth)acrylate, a repeating unit derived from a pyrrolidone monomer, a nitrogen-containing repeating unit such as -[CH₂C(CH₃)[COOCH₂CH₂CH₂N⁺(CH₃)₃.Cl]]-, and an anionic functional group-containing repeating unit such as -[CH₂C(CH₃)COOH]- has a relatively low viscosity, and the action of the treatment agent hardly lowers even when a cationic paper strength-enhancing agent is used in combination therewith.