Amphoteric amine based polymers having a net cationic charge and process for their production

Process for the production of amphoteric amine containing polymers having a net cationic charge which comprises reacting

• (a) at least one amine selected from the group consisting of linear alkylamines, branched alkylamines, cycloalkylamines, alkoxyamines, amino alcohols, cyclic amines containing at least one nitrogen atom in a ring structure, alkylenediamines, polyetherdiamines, polyalkylenepolyamiaes, mixtures of one of the said amines with at least one amino acid or a salt thereof, reaction products of the said amines with at least one anionic group containing alkylating agent wherein per mole of NH group of the amines of from 0.04 to 0.6 moles of the anionic group containing alkylating agent is reacted, and mixtures thereof,
• with
• (b) at least one crosslinking agent selected from the group consisting of epihalohydrins, bishalohydrins of diols, bis-(halohydrins) of polyalkylene glycols, bis-(halohydrins) of polytetrahydrofurane, alkylene dihalides, alkylene trihalides, bisepoxides, triepoxides, tetraepoxides, and mixtures thereof,
• in a molar ratio of (a):(b) of from 2:1 to 1:1.5 and
• (c) reacting the condensation products of (a) and (b) which are free of anionic groups with an anionic group containing alkylating agent or oxidizing their tertiary nitrogen atoms to N-oxides in such an amount that the resulting polymers have a net cationic charge.