Abstract: The present invention relates to a method for zinc phosphating of metal surfaces using a colloidal aqueous solution as activation stage, a zinc phosphate layer having a layer weight of less than 2.0 g/m2 being deposited on surfaces of zinc in the method step following activation. The activation stage is based on a colloidal aqueous solution containing a dispersed particulate constituent, the particulate constituent containing, in addition to dispersed inorganic compounds of phosphates of polyvalent metal cations, a polymeric organic compound as a dispersing agent that is composed at least partially of styrene and/or an ?-olefin having no more than 5 carbon atoms, the polymeric organic compound additionally comprising units of maleic acid, their anhydride and/or their imide and the polymeric organic compound additionally comprising polyoxyalkylene units.

Abstract: The present invention relates to an aqueous dispersion as a concentrate for the activation stage of phosphating of metal surfaces, containing a dispersed particulate constituent and a thickener, the particulate constituent containing, in addition to dispersed inorganic compounds of polyvalent metal cations, polymeric organic compounds as dispersing agents which are composed at least partially of styrene and/or an ?-olefin having no more than 5 carbon atoms and maleic acid, its anhydride and/or its imide, and which additionally comprise polyoxyalkylene units. The aqueous dispersion is further characterized by a D50 value above 10 ?m. The present invention also relates to a method for anti-corrosion pretreatment of the surfaces of a metal material, in particular for zinc phosphating.

Abstract: The present invention relates to an aqueous coating composition (A) having a pH in a range from 4.0 to 6.

Abstract: The present invention relates to a process for the at least two-stage coating of an electrically conductive substrate, the at least two-stage coating being carried out in a single dip-coating bath, the dip-coating bath comprising a coating material composition which comprises at least one cathodically depositable film-forming polymer and also an anodically depositable component, the anodically depositable component comprising anions of at least one phosphorus oxoacid; in a first stage, the electrically conductive substrate for coating is connected as anode in said dip-coating bath, and in a subsequent stage the now precoated substrate is connected as cathode in said dip-coating bath. The invention further relates to a substrate coated by the process of the invention.

Abstract: The present invention relates to an aqueous coating composition (A) having a pH in a range from 4.0 to 6.

Abstract: A process for anticorrosion treatment of bare metal surfaces comprising steel surfaces, comprising contacting the bare metal surfaces with an acidic aqueous solution of a fluoro complex of at least one element M selected from the group B, Si, Ti, Zr and Hf, at least one further component selected from among: a buffer system for the pH range from 2.5 to 5.5, nitrate ions, copper ions, silver ions, vanadium or vanadate ions, bismuth ions, magnesium ions, zinc ions, manganese ions, cobalt ions, nickel ions, tin ions, aromatic carboxylic acids with at least two groups containing donor atoms, or derivatives of such carboxylic acids, and silica particles with an average particle size of below 1 ?m; and contains no more than 1 mg/l of an organic polymer with allylamine or vinylamine monomers; then rinsing the metal surfaces with water and thereafter coating them with a cathodically depositable electro-dipcoating.

Abstract: The present invention relates to a chromium-free aqueous agent based on water-soluble compounds of titanium and/or zirconium and a source of fluoride ions, copper ions and metal ions selected from the group consisting of calcium, magnesium, aluminum, boron, zinc, iron, manganese and/or tungstene and to a method for the anti-corrosive conversion treatment of metal surfaces. The chromium-free aqueous agent is suitable for the treatment of various metal materials, joined in composite structures, amongst others of steel or galvanized steel or the alloys thereof or any combinations of said materials. Furthermore, surfaces of aluminum and alloys thereof can be treated in an anti-corrosive manner using the agent according to the invention. The anti-corrosive treatment is intended in particular as a pretreatment for a subsequent dip-coating.

Abstract: The present invention relates to a method for improving the corrosion-protecting pre-treatment of metal surfaces and using rinse water in a manner to conserve resources in such a corrosion-protecting pre-treatment, comprising a conversion treatment step using an aqueous composition comprising at least 50 ppm of the elements B, Si, Ti, Zr and/or Hf in the form of water-soluble compounds at a pH value of 3 to 5.5, wherein a minimum fraction of 10 ppm of the elements B, Si, Ti, Zr and/or Hf in the form of water-soluble compounds is present in the last pre-rinse step and a portion of the aqueous composition of the conversion treatment step is contained in the first post-rinse step. The resource-conserving use of the rinse water is accomplished according to the invention by way of a cascaded return of rinse water from the last rinse step to the first rinse step.

Abstract: The present invention relates to a multistage method for the corrosion-protective and adhesion-promoting treatment of metal surfaces, comprising a first method step for passivating pretreatment using an acidic aqueous composition (A) containing water-soluble compounds of Zr and/or Ti and fluoride ions, a subsequent method step for post-treatment using an aqueous composition (B) containing at least one organic compound having at least one aromatic heterocyclic compound, wherein the aromatic heterocyclic compound has at least one nitrogen atom. The invention further relates to a metal surface treated according to the method according to the invention and the use of said treated metal surface for subsequent coating with an organic binding agent system.

Abstract: The present invention relates to a multistage method for the corrosion-protective and adhesion-promoting treatment of metal surfaces, comprising a first method step for passivating pretreatment using an acidic aqueous composition (A) containing water-soluble compounds of Zr and/or Ti and fluoride ions, a subsequent method step for post-treatment using an aqueous composition (B) containing at least one organic compound having at least one aromatic heterocyclic compound, wherein the aromatic heterocyclic compound has at least one nitrogen atom. The invention further relates to a metal surface treated according to the method according to the invention and the use of said treated metal surface for subsequent coating with an organic binding agent system.

Abstract: The present invention relates to a method for improving the corrosion-protecting pre-treatment of metal surfaces and using rinse water in a manner to conserve resources in such a corrosion-protecting pre-treatment, comprising a conversion treatment step using an aqueous composition comprising at least 50 ppm of the elements B, Si, Ti, Zr and/or Hf in the form of water-soluble compounds at a pH value of 3 to 5.5, wherein a minimum fraction of 10 ppm of the elements B, Si, Ti, Zr and/or Hf in the form of water-soluble compounds is present in the last pre-rinse step and a portion of the aqueous composition of the conversion treatment step is contained in the first post-rinse step. The resource-conserving use of the rinse water is accomplished according to the invention by way of a cascaded return of rinse water from the last rinse step to the first rinse step.

Abstract: The present invention relates to a chromium-free aqueous agent based on water-soluble compounds of titanium and/or zirconium and a source of fluoride ions, copper ions and metal ions selected from the group consisting of calcium, magnesium, aluminum, boron, zinc, iron, manganese and/or tungstene and to a method for the anti-corrosive conversion treatment of metal surfaces. The chromium-free aqueous agent is suitable for the treatment of various metal materials, joined in composite structures, amongst others of steel or galvanized steel or the alloys thereof or any combinations of said materials. Furthermore, surfaces of aluminum and alloys thereof can be treated in an anti-corrosive manner using the agent according to the invention. The anti-corrosive treatment is intended in particular as a pretreatment for a subsequent dip-coating.

Abstract: A process for anticorrosion treatment of bare metal surfaces comprising steel surfaces, wherein the bare metal surfaces are contacted with an acidic aqueous solution of a fluoro complex of at least one element M selected from the group B, Si, Ti, Zr and Hf, at least one further component which is selected from among: a buffer system for the pH range from 2.5 to 5.5, nitrate ions, copper ions, silver ions, vanadium or vanadate ions, bismuth ions, magnesium ions, zinc ions, manganese ions, cobalt ions, nickel ions, tin ions, aromatic carboxylic acids with at least two groups containing donor atoms, or derivatives of such carboxylic acids, and silica particles with an average particle size of below 1 ?m; and contains no more than 1 mg/l of an organic polymer with allylamine or vinylamine monomers; the metal surfaces are then rinsed with water and thereafter are coated with a cathodically depositable electro-dipcoating.