Method for coating metal surfaces with an activating agent prior to phosphating

An aqueous colloidal activating agent A, which was prepared by mixing, compounding or granulating the components, or aqueous colloidal activating agent C, which was prepared from an aqueous colloidal activating agent A using a powdered activating agent B and in which the powdered activating agent B was then dissolved and dispersed in water for application, or aqueous colloidal activating agent E, which was prepared from an aqueous colloidal activating agent A using an aqueous colloidal activating agent D and in which the aqueous activating agent E was prepared by diluting with water, or aqueous colloidal activating agent G, which was prepared from a powdered activating agent F, the powdered activating agent F being prepared substantially by mixing, compounding or granulating the components and the aqueous colloidal activating agent G being prepared therefrom by dissolving and dispersing in water, the term “colloidal” referring only to titanium phosphate colloids, the colloidal activating agent containing titanium phosphate and at least one further, non-titanium-containing, phosphate and in the concentration for a treatment bath serving for the treatment of metallic surfaces prior to phosphating, wherein the colloidal activating agent also contains at least one water-soluble silicon compound having at least one organic group selected from alkoxysilanes and aminosilanes, in particular as hydrolysed or condensed silane/silanol/siloxane/polysiloxane, wherein the total content of water-soluble silicon compounds having at least one organic group in the activating agent is in the range from 0.0001 to 0.2 g/l, calculated in each case as silane or as the corresponding silicon-containing starting compound that is principally present.