Abstract: An acid zinc alloy electroplating bath such as a zinc-nickel and/or cobalt bath and process employing said bath which contains an effective amount of a brightening agent selected from a bath soluble polyacrylamide polymer, N-substituted polyacrylamide derivative, and copolymers thereof. The zinc alloy electroplating is economical and versatile in use and produces a ductile, corrosion resistant plating deposit having a semi-bright to bright appearance.

Abstract: A method for the treatment of aluminum surfaces to provide them with a corrosion resistant, hydrophilic coating. The aluminum surfaces are first provided with a corrosion-resistant film and, thereafter, a coating of fine silica particles is applied to the corrosion resistant film. Suitable corrosion resistant films which may be used are anodized films, boehmite films, chromated films and organic resin films. The coated aluminum surfaces produced by this method are found to have particular application for aluminum heat exchangers.

Abstract: A process for the phosphatizing of metals, particularly iron, steel and zinc, in which the metal is contacted with acidic aqueous zinc phosphate solutions, containing an oxidizing agent, which containfrom 0.4 to 1.5 g/liter of Zn,from 0 to 1.3 g/liter of Ni andfrom 10 to 26 g/liter of P.sub.2 O.sub.5,and in which the weight ratio of Zn to P.sub.2 O.sub.5 is adjusted to a value of (from 0.012 to 0.12):1 and of Ni to Zn to a value of (from 0 to 1.5):1, and the bath is supplemented with a concentrate, in which Zn, Ni and P.sub.2 O.sub.5 are present in a weight ratio of (from 0.18 to 0.33:(from 0 to 0.06):1, so as to obtain satisfactory phosphatizing results over a long period.Preferably, the zinc phosphatizing solutions, which, in addition, may also contain simple or complex fluorides and compounds that reduce the weight of the coat, are applied at a temperature within the range of from 30.degree. to 65.degree. C.

Abstract: An aqueous acidic zinc phosphate solution which contains at least 6 g/l of Zn, at least 5 g/l P.sub.2 O.sub.5, at least 1.0 g/l of an accelerator, calculated as ClO.sub.3, from about 1 to about 50 g/l of sulfate ion, which solution has a total acid number of at least 20, a weight ratio of free P.sub.2 O.sub.5 of 0.2-0.6:1 and a weight ratio of P.sub.2 O.sub.5 : Zn: ClO.sub.3 of 1:0.5-4.0: 0.01-1.0. The phosphatizing bath preferably contains from about 1 to 5 g/l chlorate in combination with at least 8 g/l nitrate, with a weight ratio of P.sub.2 O.sub.5 : NO.sub.3 of 1:0.2-6.0. The baths may be used to form phosphate coatings on ferrous metal surfaces using immersing or flow coating techniques and the phosphate coatings formed are found to have increased thickness and adhesion or coalescence to the metal surface.

Abstract: A composite electroplated article and process for making same comprising a body having a plurality of adherent electroplates of controlled thickness and composition thereon. The first layer comprises a nickel-iron alloy containing about 15 to about 50 percent by weight iron; the second layer comprises a nickel-containing plate of a sulfur content of about 0.02 to about 0.5 percent by weight; the third layer comprises a nickel-iron alloy containing about 5 to about 19 percent by weight iron but less iron than the first layer. Optionally, a decorative chromium outer layer is applied to the surface of the third layer, and preferably, an intervening nickel plate is interposed between the third layer and outer chromium layer of a type selected to induce micro-discontinuities in the outer chromium layer.

Abstract: Electroplating baths for producing semi-bright, ductile, low stressed nickel deposits in an electrodeposition process utilizing insoluble anodes are disclosed. The nickel baths contain, in addition to nickel salts, ortho-formyl benzene sulfonic acid and perfluorocyclohexyl potassium sulfonate.

Abstract: A method of electrodepositing a gold alloy layer having improved corrosion protection is disclosed. Prior to the gold layer an underlayer of ductile, low-stress nickel is electrodeposited from a solution containing ortho-formyl benzene sulfonic acid and perfluorocyclohexyl potassium sulfonate.

Abstract: There is disclosed a chemical stripping solution suitable for removing tin and tin-lead alloys from metallized, e.g. copper coated, substrates so as to leave the said substrate reusable comprising an aqueous solution of hydrogen peroxide in an amount of 0.1 to 10 molar, ammonium bifluoride in an amount of 0.4 to 10 molar, an acid of a type and in an amount such as to maintain the pH of the solution at the surface being stripped below the value at which smut formation occurs whereby effective stripping is achieved in use, and a metal complexing compound in an amount of at least 0.005 molar, the said metal complexing compound comprising 8-hydroxyquinoline or an 8-hydroxyquinoline derivative or a substituted 8-hydroxyquinoline and wherein the molar ratio ammonium bifluoride to complexor is at least 125:1 and the molar ratio of hydrogen peroxide to complexor is at least 50:1.

Abstract: An improved electrolytic bath composition and process for stripping relatively thick copper, copper alloy, or chromium deposits from a ferrous basis metal comprising an aqueous solution having a pH of from about 1 to about 14 and consisting essentially of an amine, nitro, and/or nitrate stripping component; and sodium glucoheptonate present in an effective amount to inhibit attack of the basis metal.

Abstract: A process for the electrodeposition of palladium in which palladium is electrodeposited from an aqueous plating bath which contains a bath soluble palladium compound, an electrolyte compound and a nitrite compound in an amount sufficient to provide an excess of free nitrite ions relative to the palladium ions. In a preferred embodiment, the bath also contains a buffering agent to maintain the bath pH at from about 6.5 to 7.5. The electrodeposition is carried out using an insoluble anode, while maintaining the excess of free nitrite ions in the bath relative to the palladium ions. In this manner, the plating efficiency of the bath is maintained at a substantially constant, high level for extended periods of plating at current densities in excess of 10 amps per square decimeter.

Abstract: A zinc alloy plating bath comprises a conductive aqueous solution containing zinc ions and nickel and/or cobalt ions and a brightening additive which is a derivative of .beta.-aminopropionic acid or a polymer thereof. A semi-bright to bright zinc alloy deposit can be electrodeposited from the bath onto a substrate.

Abstract: A pickling and rust-removing paste composition suitable for cleaning metal surfaces, including surfaces of steel and aluminum. The composition contains fluoride ions and a mixture of calcium compounds and tervalent iron and/or aluminum compounds and has an acidity corresponding to at least 10% by weight of free acid, calculated at 100% HF. The composition also most preferably contains at least one anion selected from nitrate, sulfate, phosphate and chloride and has an acidity corresponding to from about 15 to 30% by weight of free acid, calculated as 100% HF.The composition is applied to that portion of the metal surface, such as steel or aluminum, to be treated and is retained in contact with the surface for a period of time sufficient to effect the desired pickling and/or removal of rust on the surface.

Abstract: A process and solution for electrolytically stripping metal deposits, particularly nickel and nickel-iron alloy deposits from a copper or copper alloy basis metal such as brass, for example, in which the aqueous stripping solution contains controlled effective amounts of halide salts, an organic carboxy acid, metal salts and mixtures thereof and hydrogen ions to provide a pH of less than about 5. The stripping of the metal deposit from the basis metal is effected by immersing the object in the stripping bath while anodically charged and passing electric current through the bath between the cathode and the object for a period of time sufficient to achieve the desired magnitude of stripping of the metal deposit.

Abstract: A zinc plating bath comprises a conductive aqueous solution containing zinc ions and a brightening additive which is a derivative of .beta.-aminopropionic acid or a polymer thereof. A ductile zinc deposit having a uniform high degree of brightness can be electrodeposited from the bath onto a substrate.

Abstract: An aqueous acidic trivalent chromium electrolyte and process for electrodepositing chromium platings comprising an electrolyte containing trivalent chromium ions, a complexing agent, halide ions, ammonium ions and a reducing agent comprising vanadium ions present in an amount effective to maintain the concentration of hexavalent chromium ions formed in the bath at a level at which satisfactory chromium electrodeposits are obtained.

Abstract: Electroplating baths suitable for obtaining white deposits of palladium metal. The bath comprises diaminodinitrite, an ammonium salt, and a sufficient amount of ammonium hydroxide to obtain a bath pH of about 9. Buffers such as ammonium biborate may be employed to maintain the necessary bath pH during electroplating operations to produce a thin, white deposit of palladium metal. The process of using such electroplating baths to produce white deposits of palladium metal on substrates is also disclosed and claimed.

Abstract: A composition for the phosphatizing of metals, particularly iron and steel, which comprises an aqueous acidic, chlorate-containing zinc phosphate solution which containsfrom 0.5 to 1.5 g/liter Znfrom 0.4 to 1.3 g/liter Nifrom 10 to 26 g/liter P.sub.2 O.sub.5from 0.8 to 5 g/liter Cl0.sub.3and in which no nitrite is added, and in which the weight ratio ofZn to Ni shall be adjusted to a value of 1: (from 0.5 to 1.5), that of Zn to P.sub.2 O.sub.5 to a value of 1: (from 8 to 85) and that of free P.sub.2 O.sub.5 to a value of from (0.005 (at about 30 degrees C.) to 0.06 (at about 60 degrees C.)): 1.The composition is particularly useful in processes for the preparation of metal surfaces for electrophoretic coating, particularly for cathodic immersion coating.

Abstract: An improved composition and process for producing a composite nickel-containing electroplate on a substrate including an inner nickel-containing layer of an average sulfur content of less than about 0.03 percent by weight, an intermediate nickel-containing layer of an average sulfur content of about 0.05 to about 0.5 percent by weight and an adjacent adherent outer nickel layer of an average sulfur content of about 0.02 to about 0.15 percent but less in sulfur than the intermediate layer and higher in sulfur than the inner layer. The controlled amount of sulfur is introduced into at least the intermediate layer by employing an aqueous acidic nickel solution containing a controlled amount of a thiazole compound so as to provide an intermediate nickel-containing deposit containing the specified average sulfur content.

Abstract: Described is an aqueous base coat composition utilizing magnesium ion preferably in conjunction with at least some compounds from the group hydrofluoric acid, phosphoric acid, tannic acid, and nitric acid and exhibiting a pH of less than 7. The anti-corrosion and adhesive properties of this base coating composition allow it to be further coated with organic film formers, varnishes, lacquers, inks, etc. to form a finished product which is resistant to corrosives, humidity, impact problems, and chipping.

Abstract: An aqueous acidic solution and process for treating metal surfaces, particularly zinc and zinc alloy surfaces, for depositing a passivate film of improved clarity and hardness and to impart improved corrosion resistance thereto. The solution contains effective amounts of chromium ions substantially all of which are in the trivalent state, hydrogen ions to provide a pH of about 1.2 to about 2.5, an oxidizing agent, a bath soluble and compatible silicate compound present in an amount to provide improved corrosion protection to the substrate and increased hardness to the passivate film and at least one additional metal ion selected from the group consisting of iron, cobalt, nickel, molybdenum, manganese, aluminum, lanthanum, cerium, lanthanide mixtures as well as mixtures thereof. The treating solution may optionally further contain halide ions, a carboxylic acid or salt and a wetting agent.