Means for coating metals to protect against corrosion

The present invention relates to a composition for coating metals to protect against corrosion, which (I) a silicon-based compounds Sol, (Ii) at least one aminoalkyl-functional alkoxysilane and / or (Iii) at least one reaction product of components (i) and (ii), wherein the content of aminoalkylfunktioneller silane component from (ii) and (iii) wt .-% is in total 0.01 to 15, calculated as the aminoalkoxysilane used in each case and based on the SiO