A process for obtaining aminopolyamide-epichlorohydrin resins with a 1,3-dichloro-2-propanol content which is undetectable by ordinary means of vapor-phase chromatography. The process consists of passing the products resulting from the successive condensation of aminopolyamides and epichlorohydrin through two columns of activated carbon. In this way, aqueous resins are obtained which are free of toxic products, and which are particularly valuable as wet strength additives in the manufacture of papers for medical, cosmetic or food contact uses.