The present invention relates to a method for treating an inkjet recording element to improve the image quality of such an element. The method comprises the applying of a solution of an aluminosilicate polymer on said recording element, said aluminosilicate polymer being obtainable by a preparation method consisting in treating an aluminum halide with an alkyl orthosilicate only having hydrolisable substituents or with a mixture of at least one silicon alcoxide only having hydrolisable substituents and at least one silicon alcoxide having a non-hydrolisable substituent with an aqueous alkali in the presence of silanol groups, the aluminum concentration being maintained less than 0.3 mol/l, the Al/Si molar ratio being maintained between 1 and 3.6 and the alkali/Al molar ratio being maintained between 2.3 and 3; and then stirring the resulting mixture at ambient temperature in the presence of silanol groups for long enough to form the aluminosilicate polymer.