The invention relates to a machine for chromatogenous grafting treatment of a scrolling substrate (S) having a hydroxylated face (Fh), comprising: an application device (3) of a grafting reagent on the hydroxylated face (Fh) of the substrate, a heating roller (4) for the development of the grafting reaction on the hydroxylated face (Fh) of the substrate, said roller (4) being provided with a bar-end system (5a, 5b) for applying a face of the substrate (S) against said heating roller (4), an extraction device (6) of the hydrochloric acid produced during the grafting reaction, an application device (7) of an air knife on the treated face of the substrate for eliminating the residual grafting reagent. The invention also relates to a chromatogenous grafting process used in said machine.