Copolymerizable monomers

As examples of the copolymerizable monomers, for example, (meth) acrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, containing carboxyl groups, such as isocrotonic acid monomer or its anhydride; vinyl sulfonic acid sulfonic acid group-containing monomers such as sodium; styrene, aromatic vinyl compounds such as substituted styrenes; a cyano group-containing monomers such as acrylonitrile, vinyl esters such as vinyl acetate, ethylene, propylene, olefins such as butadiene; vinyl chloride; acrylamide, methacrylamide, N- vinylpyrrolidone, N, N- dimethyl (meth) amide group-containing monomers such as acrylamide; (meth) acrylic acid hydroxyalkyl, hydroxyl group-containing monomers such as glycerine dimethacrylate ; (meth) aminoethyl acrylate, (main ) Amino group-containing monomers such as acryloyl morpholine; cyclohexyl maleimide, imide group-containing monomers such as isopropyl maleimide; (meth) acrylate, glycidyl (meth) an epoxy group-containing monomers such as methyl acrylate glycidyl; 2 – other methacryloyloxyethyl isocyanate isocyanate group-containing monomers such as triethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, ethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, neo neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate Dipentaerythritol hexa (meth) acrylate, a polyfunctional copolymerizable monomer (polyfunctional monomer) such as divinylbenzene, and the like. Copolymerizable monomers may be used alone or in combination. As the copolymerizable monomer, there can be used a modified monomer having a functional group such as a carboxyl group suitably.