Abstract: The invention relates to a method for zinc phosphating components comprising surfaces made of zinc in order to suppress the formation of insoluble phosphation constituents removably adhered to the zinc surfaces and thus further improve the adhesion of dip-paint coatings applied later. In the method, a process is used of activating the zinc surfaces by means of dispersions containing particulate hopeite, phosphophyllite, scholzite, and/or hureaulite, wherein the proportion of particulate phosphates in the activation process must be adapted to the quantity of free fluoride and dissolved silicon in the zinc phosphation.

Abstract: The invention relates to a method for zinc phosphating components so as to form layers, said components comprising surfaces made of steel with a high tolerance against aluminum dissolved in the zinc phosphating bath, wherein the precipitation of poorly soluble aluminum salts can be largely prevented. In the method, a process is used of activating the zinc surfaces by means of dispersions containing particulate hopeite, phosphophyllite, scholzite, and/or hureaulite, wherein the proportion of particulate phosphates in the activation process must be adapted to the quantity of free fluoride and dissolved aluminum in the zinc phosphation.

Abstract: A method for anti-corrosion coating of metal components, in series, comprising a plurality of wet-chemical treatment steps concluding in cathodic electrodeposition, in which method each component is received by a conveying rack; then the component and conveying rack proceed through all treatment steps; the finished coated component is separated from the conveying rack; and an uncoated component is then received by the same conveying rack for coating; wherein build-up of solid coating deposits on the conveying rack is prevented by using an additional treatment step before cleaning/degreasing, passivation and electrodeposition, thereby avoiding extraction of individual conveying elements for removing coating deposits; wherein removal of cathodic electrodeposition coating constituents from conveying racks is achieved by contacting the conveying racks carrying components to be coated with an aqueous acidic agent, containing phosphoric acid, before the wet-chemical treatment steps for cleaning/degreasing, passivat

Abstract: The invention relates to a method for zinc phosphating components comprising surfaces made of zinc in order to suppress the formation of insoluble phosphation constituents removably adhered to the zinc surfaces and thus further improve the adhesion of dip-paint coatings applied later. In the method, a process is used of activating the zinc surfaces by means of dispersions containing particulate hopeite, phosphophyllite, scholzite, and/or hureaulite, wherein the proportion of particulate phosphates in the activation process must be adapted to the quantity of free fluoride and dissolved silicon in the zinc phosphation.

Abstract: The invention relates to a method for zinc phosphating components so as to form layers, said components comprising surfaces made of steel with a high tolerance against aluminum dissolved in the zinc phosphating bath, wherein the precipitation of poorly soluble aluminum salts can be largely prevented. In the method, a process is used of activating the zinc surfaces by means of dispersions containing particulate hopeite, phosphophyllite, scholzite, and/or hureaulite, wherein the proportion of particulate phosphates in the activation process must be adapted to the quantity of free fluoride and dissolved aluminum in the zinc phosphation.

Abstract: A method for corrosion protection treatment, comprising contacting a series of components having metallic surfaces of iron and/or zinc with a passivating aqueous pretreatment solution, present in a system tank, containing compounds of the elements zirconium and/or titanium, and contacting with a source of fluoride ions wherein a portion of the pretreatment solution is discarded and replaced with a volume portion of one or more such replenishment solutions which in total are at least of equal size, by metered addition to the system tank of the pretreatment and wherein discarding as a function of the molar ratio of the elements fluorine to zirconium and/or titanium must not drop below a predefined value, the metered addition of replenishment solution takes place such that maintaining the concentration of the elements zirconium and/or titanium in the passivating aqueous pretreatment solution in the form of water-soluble compounds is ensured.

Abstract: The present invention relates to a method for the serial surface treatment of metal components that have zinc surfaces, wherein the method comprises an alkaline pretreatment, and a method for the selective removal of zinc ions from an alkaline bath solution for the serial surface treatment of metal surfaces that have zinc surfaces. According to the invention, in order to perform each method, part of the alkaline aqueous bath solution is brought in contact with an ion exchange resin that bears functional groups selected from —OPO3X2/n and/or —PO3X2/n, wherein X is either a hydrogen atom or an alkali metal and/or alkaline-earth metal atom to be exchanged having the particular valency n.

Abstract: A method for corrosion protection treatment, comprising contacting a series of components having metallic surfaces of iron and/or zinc with a passivating aqueous pretreatment solution, present in a system tank, containing compounds of the elements zirconium and/or titanium, and contacting with a source of fluoride ions wherein a portion of the pretreatment solution is discarded and replaced with a volume portion of one or more such replenishment solutions which in total are at least of equal size, by metered addition to the system tank of the pretreatment and wherein discarding as a function of the molar ratio of the elements fluorine to zirconium and/or titanium must not drop below a predefined value, the metered addition of replenishment solution takes place such that maintaining the concentration of the elements zirconium and/or titanium in the passivating aqueous pretreatment solution in the form of water-soluble compounds is ensured.

Abstract: The present invention relates to a method for the serial surface treatment of metal components that have zinc surfaces, wherein the method comprises an alkaline pretreatment, and a method for the selective removal of zinc ions from an alkaline bath solution for the serial surface treatment of metal surfaces that have zinc surfaces. According to the invention, in order to perform each method, part of the alkaline aqueous bath solution is brought in contact with an ion exchange resin that bears functional groups selected from —OPO3X2/n and/or —PO3X2/n, wherein X is either a hydrogen atom or an alkali metal and/or alkaline-earth metal atom to be exchanged having the particular valency n.

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 an aqueous alkaline composition (A) for alkaline passivation of metallic components comprising at least in part surfaces of zinc or zinc alloys, containing iron(III) ions, phosphate ions, and one or more complexing agents, where a free alkalinity ranges from 1 to 6 points, and the pH is at least 11. The aqueous compositions (A) can additionally contain nonionic surfactants, so that such compositions are suitable for use in a method in which both cleaning and alkaline passivation of the metallic component occur in one step. The present invention further relates to a method for alkaline passivation of metallic components by contacting them with composition (A), and further a method for surface treatment in automobile body production, in which the alkaline passivation step using composition (A) is followed by an acid passivation step using a composition (B).

Abstract: A method for recovering demineralized water from zirconium-containing rinse water having a pH lower than 6.0, wherein a) the rinse water has added to it an aqueous solution of Ca(OH)2 containing no more than 0.1 wt % undissolved Ca(OH)2, in a quantity such that the pH of the rinse water rises to a value in the range from 6.2 to 8.0, b) a precipitate that forms is separated from the rinse water, and c) the rinse water from which the precipitate was removed in step b) is subjected to an ion exchange method or to reverse osmosis.

Abstract: The invention relates to an aqueous composition and to a method for the anticorrosion conversion treatment of metallic surfaces, particularly metallic materials which are assembled into composite structures, comprising steel or galvanized or alloy-galvanized steel and any combinations thereof, the composite structure being composed at least in part of aluminum or the alloys thereof. The aqueous composition according to the invention is based on a phosphating solution and contains, in addition to water-soluble compounds of zirconium and titanium, a quantity of free fluoride in a ratio that both permits phosphating of the steel and galvanized and/or alloy-galvanized steel surfaces and determines low pickling rates of the aluminum substrate with simultaneous passivation of the aluminum.

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 an aqueous composition and to a method for the anticorrosion conversion treatment of metallic surfaces, particularly metallic materials which are assembled into composite structures, comprising steel or galvanized or alloy-galvanized steel and any combinations of these materials, the composite structure being composed at least in part of aluminum or the alloys thereof. The aqueous composition according to the invention is based on a phosphating solution and contains, in addition to water-soluble compounds of zirconium and titanium, a quantity of free fluoride in a ratio that both permits phosphating of the steel and galvanized and/or alloy-galvanized steel surfaces and determines low pickling rates with regard to the aluminum substrate with simultaneous passivation of the aluminum.

Abstract: The invention relates to an acidic, aqueous, chromium-free composition (A) for the anti-corrosive treatment of steel and/or galvanized steel surfaces comprising metal ions (M) selected from ions at least of the elements nickel, cobalt, molybdenum, iron or tin and a multi-stage method applying the composition (A) for the anti-corrosive pre-treatment of metal components which have steel and/or galvanized steel surfaces. The invention further relates to metal surfaces of zinc or iron having a passive layer system comprising at least 30 mg/m2 nickel and at least 10 mg/m2 zircon, titanium and/or hafnium and sulfur, wherein nickel is present in metallic form at up to at least 30 At. %, obtainable in a method according to the invention.

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 an aqueous alkaline composition (A) for alkaline passivation of metallic components comprising at least in part surfaces of zinc or zinc alloys, containing iron(III) ions, phosphate ions, and one or more complexing agents, where a free alkalinity ranges from 1 to 6 points, and the pH is at least 11. The aqueous compositions (A) can additionally contain nonionic surfactants, so that such compositions are suitable for use in a method in which both cleaning and alkaline passivation of the metallic component occur in one step. The present invention further relates to a method for alkaline passivation of metallic components by contacting them with composition (A), and further a method for surface treatment in automobile body production, in which the alkaline passivation step using composition (A) is followed by an acid passivation step using a composition (B).

Abstract: The invention relates to an acidic, aqueous, chromium-free composition (A) for the anti-corrosive treatment of steel and/or galvanized steel surfaces comprising metal ions (M) selected from ions at least of the elements nickel, cobalt, molybdenum, iron or tin and a multi-stage method applying the composition (A) for the anti-corrosive pre-treatment of metal components which have steel and/or galvanized steel surfaces. The invention further relates to metal surfaces of zinc or iron having a passive layer system comprising at least 30 mg/m2 nickel and at least 10 mg/m2 zircon, titanium and/or hafnium and sulfur, wherein nickel is present in metallic form at up to at least 30 At. %, obtainable in a method according to the invention.

Abstract: A process for the anticorrosive treatment of metal components that have been heat-treated at a temperature of at least 100° C. and at least partially comprise zinc surfaces, wherein the surfaces of the component that consist of zinc already partially have a crystalline zinc phosphate layer, wherein the cleaned component is given an activating pretreatment with an acidic aqueous dispersion of insoluble phosphates having a pH of not less than 4 and the component is subsequently subjected to a phosphating conversion treatment before electrocoating is applied. The invention also comprises the use of metal components that have been treated in such a process, for the application of multilayer systems and in particular for the manufacture of bodies in automobile production.