Abstract: The present invention relates to a method for substantially nickel-free phosphating of a metallic surface, wherein a metallic surface is treated one after the other with the following compositions: i) with an alkaline, aqueous cleaner composition which comprises at least one water-soluble silicate, and ii) with an acidic, aqueous, substantially nickel-free phosphating composition which comprises zinc ions, manganese ions and phosphate ions. The invention also relates to the above cleaner composition itself and also to a metallic surface phosphate-coated by the above method, and to the use of said surface.

Abstract: Described herein is a method for treatment of at least one surface of a metal containing substrate including contacting the surface with an aqueous acidic Ni-free composition (A) including at least zinc cations, manganese cations, and phosphate anions to form a conversion coating on the surface, and contacting the formed coating with an aqueous Ni-free composition (B) including one or more linear polymers (P) containing vinyl phosphonic acid and (meth)acrylic acid in form of their polymerized monomeric units. Also described herein is a composition (B) as such, a master batch to produce the composition (B), a kit-of-parts including both compositions (A) and (B), a kit-of-parts including respective master batches to produce both compositions (A) and (B), and a coated substrate obtainable by the method described herein.

Abstract: Described herein is a method for treatment of at least one surface of a metal containing substrate including at least contacting the surface with an aqueous acidic Ni-free composition (A) including at least zinc cations, manganese cations, and phosphate anions to form a conversion coating on the surface and contacting the formed coating with an aqueous Ni-free composition (B) including one or more linear polymers (P) containing at least vinyl phosphonic acid, (meth)acrylic acid, and hydroxyethyl- and/or hydroxypropyl (meth)acrylate in form of their polymerized monomeric units. Also described herein is the composition (B), a master batch to produce the composition (B), a kit-of-parts including both compositions (A) and (B), a kit-of-parts including respective master batches to produce both compositions (A) and (B), and a coated substrate obtainable by the method described herein.

Abstract: The present invention relates to a method for substantially nickel-free phosphating of a metallic surface, wherein a metallic surface is treated one after the other with the following compositions: i) with an alkaline, aqueous cleaner composition which comprises at least one water-soluble silicate, and ii) with an acidic, aqueous, substantially nickel-free phosphating composition which comprises zinc ions, manganese ions and phosphate ions. The invention also relates to the above cleaner composition itself and also to a metallic surface phosphate-coated by the above method, and to the use of said surface.