Abstract: An aluminum material is surface-treated with an aqueous solution containing 0.005 mol/lit. or more of a chelating agent and 5 g/lit. or more of an organic amine and having 100 ppm or less of phosphoric acid radical ion concentration and 500 ppm or less of sulfuric acid radical ion concentration, until its surface has a color tone (S) of:S=(X.sup.2 +(3.388Z-3Y.sup.2).sup.1/2.gtoreq.70wherein X, Y and Z represent the tristimulus values of color.The aluminum material can be surface-treated while setting the treating conditions on the basis of a specific color tone detectable by colorimetry, without relying on experience and intuition. The surface-treated aluminum material can have a good anticorrosion, have good color change preventive properties, a good adhesion of coatings and a beautiful surface appearance.

Abstract: In a continuous surface treating method and apparatus with an inline centrifugal separator, an object to be treated is contained in a basket and hung from a hanger of an overhead type and a series of surface treatments of the object is carried out by using a continuous conveyer of a power and free type. By using a hanger attach-detach conveyer, the object is moved from a main conveyer to a sub-conveyer and an excessive treating liquid attached to the object in a previous process is separated by using the centrifugal separator. Then, the object is returned from the sub-conveyer to the main conveyer to perform a next process. The surface treating apparatus includes the rotatable basket for containing the object.

Abstract: The paint adhesion and corrosion resistance of surfaces of aluminum and its alloys, particularly when using a paint based on poly{vinyl chloride}, is improved by using a conversion coating solution having a pH in the range from 1.0 to 3.0 and consisting essentially of water and:(A) an amount of phosphate ions that is stoichiometrically equivalent to at least 5.0 g/L of phosphoric acid;(B) at least 1.0 g/L of hexavalent chromium;(C) at least 0.1 g/L of fluoride ions; and(D) a complex fluoride ion component selected from the group consisting of:(i) at least 4.0 g/L of fluosilicate ions,(ii) at least 0.5 g/L of fluoborate ions,(iii) at least 2.0 g/L of fluozirconate ions, and(iv) at least 2.0 g/L of fluotitanate ions.

Abstract: (A) A process for forming an oxide film cobalt conversion coating on a metal substrate, thereby imparting corrosion resistance and paint adhesion properties. The invention was developed as a replacement for the prior art chromic acid process. The process includes the steps of: (a) providing a cobalt conversion solution comprising an aqueous reaction solution containing a soluble cobalt-III hexacoordinated complex, the concentration of the cobalt-III hexacoordinated complex being from about 0.01 mole per liter of solution to the solubility limit of the cobalt-III hexacoordinated complex; and (b) contacting the substrate with the aqueous reaction solution for a sufficient amount of time, whereby the cobalt conversion coating is formed. The substrate may be aluminum or aluminum alloy, as well as Cd plated, Zn plated, Zn--Ni plated, and steel. The cobalt-III hexacoordinated complex may be present in the form of Me.sub.m [Co(R).sub.6 ].sub.

Abstract: An aluminum sheet for use in spot welding has an anodic oxide film with a thickness of 50 .mu.m or less on at least one surface thereof. The anodic oxide film is preferably overlaid with a plating layer predominantly comprising at least one metal selected from the group consisting of Zn, Cr, Co, Ni, Fe, and Mn. The aluminum sheet can be produced by subjecting an aluminum or aluminum alloy sheet to anodic oxidation in an acidic solution having a pH of 4 or less conditions of from 2 to 200 V in voltage and from 0.2 to 200 seconds in duration, optionally followed by electroplating in an acidic plating bath.

Abstract: A non-toxic corrosion resistant conversion coating for aluminum is formed by a process which includes subjecting the aluminum to an acidic aqueous solution containing potassium permanganate and cerous chloride, alone or in combination with strontium chloride. The corrosion resistance is improved by a subsequent treatment in an alkaline solution containing molybdate, nitrite and metasilicate ions. The corrosion resistant is further improved by treating the coated surface with an acholic solution containing glycidoxy(epoxy)polyfunctionalmethoxysilane, alone or in combination with phenyltrimethoxysilane. The coating thus produced is a mixture of oxides and hydroxides of cerium strontium and aluminum. These oxides and hydroxides may also be intermixed with molybdate silicate and nitrite ions. In the most corrosion resistant form the mixture further includes a silane overcoat.

Abstract: Conversion coatings containing elpasolite and/or cryolite can be formed on aluminum substrates by contacting the substrates with an aqueous liquid composition containing adequate free fluoride ion activity and concentrations of dissolved sodium and potassium, if a potassium content in the coating is desired as is usual. The aqueous liquids preferably also contain phosphate and polyhydroxy organic compounds and may contain surfactants if a cleaning effect is desired.

Abstract: (A.) A process for forming a cobalt conversion coating on a metal substrate, thereby imparting corrosion resistance and paint adhesion properties. The invention was developed as a replacement for the prior art chromic acid process. The process includes the steps of: (a) providing a cobalt conversion solution comprising an aqueous reaction solution containing a soluble cobalt-III hexacoordinated complex, the concentration of the cobalt-III hexacoordinated complex being from about 0.01 mole per liter of solution to the saturation limit of the cobalt-III hexacoordinated complex, and acetic acid; and (b) contacting the substrate with the aqueous reaction solution for a sufficient amount of time, whereby the cobalt conversion coating is formed. The substrate may be aluminum or aluminum alloy, as well as Cd plating, Zn plating, Zn--Ni plating, and steel. The cobalt-III hexacoordinated complex may be present in the form of [Co(NH.sub.3).sub.6 ]X.sub.3 wherein X is Cl, Br, NO.sub.3, CN, SCN, 1/3PO.sub.4, 1/2SO.sub.

Abstract: Copper alloys of aluminum are afforded extended protection against surface corrosion by anodizing the aluminum surface to be protected, treating the surface with a heterocyclic aromatic azole treating agent having up to 16 carbon atoms before, during or after the anodizing step, and coating the treated surface after anodize with a fatty acid of 5 to 24 carbon atoms.

Abstract: A method is provided by which a corrosion-resistant barrier layer composed of a rare earth oxide coating incorporated in an oxide film is developed on the surface of a metal for the purpose of improving the corrosion resistance of the metal. The method is particularly suitable for forming a corrosion-resistant barrier on an aluminum alloy, in which the corrosion-resistant barrier layer is composed of a cerium oxide coating incorporated with a uniform aluminum oxide film which has been formed on the aluminum alloy. The corrosion-resistant barrier layer exhibits a broader passivation range as compared to chromium conversion coatings typically used in the art. Simultaneously, the method of this invention avoids the environmental hazards associated with chromium conversion processes, making the method more suitable for manufacturing operations. Furthermore, the method of this invention does not employ hazardous compounds, making the process suitable for a manufacturing environment.

Abstract: Heating an aqueous mixture of a fluoroacid such as H.sub.2 TiF.sub.6 and an oxide, hydroxide, and/or carbonate such as silica produces a clear mixture with long term stability against settling of any solid phase, even when the oxide, hydroxide, or carbonate phase before heating was a dispersed solid with sufficiently large particles to scatter light and make the mixture before heating cloudy. The clear mixture produced by heating can either be mixed with water soluble and/or water dispersible polymers, for example with dispersed polymers of the diglycidyl ether of bisphenol-A or an acrylic acid polymer, or with soluble hexavalent and/or trivalent chromium, to produce a composition that improves the corrosion resistance of metals treated with the composition, especially after subsequent painting.

Abstract: A non-toxic corrosion resistant conversion coating process for aluminum and aluminum alloys which includes subjecting the aluminum to an aqueous solution containing hydrogen peroxide or cerous chloride, alone or in combination with strontium chloride. The corrosion resistance is improved by a subsequent treatment in an alkaline solution containing molybdate, nitrite and metasilicate ions. The corrosion resistant is further improved by treating the coated surface with an acholic solution containing glycidoxy(epoxy)polyfunctionalmethoxysilane, alone or in combination with phenyltrimethoxysilane. The coating thus produced is a mixture of oxides and hydroxides of cerium, strontium and aluminum. These oxides and hydroxides may also be intermixed with molybdate silicate and nitrite ions. In the most corrosion resistant form the mixture further includes a silane overcoat.

Abstract: A substantially chromium free composition and method for passivating a galvanized metal surface is disclosed. The passivation treatment which may be rinsed or dried-in-place includes phosphoric acid, boric acid and optionally molybdic acid.

Abstract: (A.) A process for forming a cobalt conversion coating on a metal substrate, thereby imparting corrosion resistance and paint adhesion properties. The invention was developed as a replacement for the prior art chromic acid process. The process includes the steps of: (a) providing a cobalt conversion reaction solution comprising an aqueous, alkaline solution containing a soluble cobalt-III hexacoordinated complex, the concentration of the cobalt-III hexacoordinated complex being from about 0.1 mole per gallon of solution to the saturation limit of the cobalt-III hexacoordinated complex; and (b) contacting the substrate with the aqueous reaction solution for a sufficient amount of time, whereby the cobalt conversion coating is formed. The substrate may be aluminum or aluminum alloy, as well as Cd plating, Zn plating, Zn-Ni plating, and steel. The cobalt-III hexacoordinated complex may be present in the form of [Co(NH.sub.3).sub.6 ]X.sub.3 wherein X is Cl, Br, NO.sub.3, CN, SCN, Y.sub.3 PO.sub.4, SO.sub.4, C.

Abstract: A surface treatment chemicals for aluminum or its alloy consisting essentially of 10-1000 parts by weight of niobium ion and/or tantalum ion, and 1-50 parts by weight of effective fluorine ion, and optionally 10-500 parts by weight of zirconium ion and/or titanium ion and 10-500 parts by weight of phosphate ion. A surface treatment bath is produced by diluting the surface treatment chemicals so as to have a pH of 1.5-4.0. Excellent resistance to blackening by boiling water and adhesion to an overlying polymer coating film can be obtained by a surface treatment using this bath.

Abstract: Heating an aqueous mixture of a fluoroacid such as H.sub.2 TiF.sub.6 and an oxide, hydroxide, and/or carbonate such as silica produces a clear mixture with long term stability against settling of any solid phase, even when the oxide, hydroxide, or carbonate phase before heating was a dispersed solid with sufficiently large particles to scatter light and make the mixture before heating cloudy. The clear mixture produced by heating can either be mixed e with water soluble and/or water dispersible polymers that are polyhydroxyalkylamino- substituted polymers and/or copolymers of p-vinyl phenol, or with soluble hexavalent and/or trivalent chromium, to produce a composition that improves the corrosion resistance of metals treated with the composition, especially after subsequent painting.

Abstract: This invention relates to Al plates suitable for automobile body panels and also relates to a method of pretreatment for painting. The features are: A Zn plating layer having 0.05.about.0.38 g/m.sup.2 of coating weight is formed on the surface of an Al plate or Al alloy plate by a displacement plating process or electroplating process. The coated Al or Al alloy plate is subjected to chemical conversion treatment with zinc phosphate under conditions to completely dissolve the zinc plating layer. This invention prevents the occurrence of filiform rusting and blistering after painting.

Abstract: Seal coating compositions and method of applying same, to metallic surfaces, particularly aluminum or alloys thereof, containing a previously formed protective coating on the metal surface, to provide for improved corrosion resistance beyond that provided by the previously formed protective coating. Aqueous solutions of the seal coating components are applied to the metal surface containing the previously formed coating which is subsequently rinsed and dried to provide metal articles having improved resistance to corrosion.

Abstract: A method for treating the surface of an aluminum-based material so as to make the surface resistant to corrosion includes the steps of contacting the surface with an aqueous cerium non-halide solution and then contacting the surface with an aqueous cerium halide solution. These steps may optionally be followed by a step of positively charging the metal surface while in contact with an aqueous molybdenum solution.

Abstract: An method of providing a protective coating on the surface of aluminum or aluminum alloys, comprising: removing contaminants from the surface; exposing the surface to water at 50.degree. to 100.degree. C. to form a porous boehmite coating on the surface; and exposing the boehmite-coated surface to an aqueous solution comprising a cerium salt and a metal nitrate at a temperature of 70.degree. to 100.degree. C. Oxides and hydroxides of cerium are formed within the pores of the boehmite to provide the protective coating, which provides corrosion resistance and improved paint adhesion.

Abstract: Surfaces of structural components made of aluminum or aluminum alloys are chemically treated to produce an aluminum oxide coating for improved adhesive bonding to other components or to other surface layers. The oxidizing is accomplished by exposing the surface to be oxidized to a combination bath of an inorganic mineral acid and an oxidation medium for a specific time duration, so that an oxide coating is produced on the surface of the structural components, as a prerequisite for a good adhesion stability of adhesive bonds to be formed after oxidizing.

Abstract: Corrosion resistance of anodized aluminum surfaces is improved by conditioning the surface with a low molecular weight (2-7 carbon atoms) alcohol, and sealing the surface with long chain (10-24 carbon atom) carboxylic acid at low temperatures below about 35-50 degrees centigrade, the alcohol being a solvent for the acid.

Abstract: Disclosed is a method of producing a functionalized layer and an aluminum hydroxide layer on an aluminum substrate, the aluminum hydroxide layer located between the substrate and the functionalized layer. The method comprises the steps of subjecting an aluminum substrate to a hydrothermal treatment in an aqueous solution having a pH in the range of 2 to 14 to form a layer of aluminum hydroxide on said substrate and thereafter treating said aluminum substrate with a phosphorus-containing acid selected from phosphonic and phosphonic acid to form a functionalized layer on said aluminum hydroxide layer, the functionalized layer comprised of the reaction product of said acid and the layer of aluminum hydroxide.

Abstract: A material and process for providing a corrosion inhibitor cationic film on he exterior aluminum surface of a weapon when contained in a submarine launch tube. An effervescent tablet containing a corrosion inhibitor material is disposed within the launch tube with the weapon and, upon flooding of the launch tube with seawater, the effervescent tablet releases the corrosion inhibitor material into the water to form a solution that coats the exposed aluminum surfaces of the weapon with a cation film of the corrosion inhibitor material.

Abstract: The invention is a metal treating process which uses a chrome-free deoxidizing bath. The process is useful for cleaning and deoxidizing aluminum substrates followed by conversion coating of the cleaned and deoxidized substrates.

Abstract: This invention provides an aluminum alloy conversion coating composition and a process for protecting aluminum alloys, especially the alloys having greater than 1.0% Cu with a conversion coating. The coating is placed on the aluminum alloy in a multi-step process. In a first step the alloy is treated with a composition having as essential ingredients aluminum nitrate and an alkali metal nitrate, in a second step the nitrate treated alloy is treated with an alkali metal permanganate composition and in the final step the alloy is treated with an alkali metal silicate composition.The aluminum conversion coatings of this invention are provided without the need for using toxic chromium compounds.

Abstract: The invention relates to a compound cable, such as an aluminum cable, an aluminum alloy cable, aluminum cable steel reinforced or an aluminum alloy cable steel reinforced with reduced audible noise for use in a high voltage transmission line.The surface of each of the aluminum wires to constitute the outermost layer of the cable is treated in water or aqueous vapor of more than 90.degree. C. so as to form a hydrophilic hydrated film on said surface, or more than 3 grooves are provided on the outer periphery of each of the aluminum wires in excess of 30% of such wires to constitute the outermost layer of the cable, a hydrated film being caused to form on the surface including the grooves thereof, so that the raindrops adhering to the surface may readily disappear due to the improved hydrophilic property and draining property of the surface of the cable thereby preventing the development of the corona discharge.

Abstract: A method of rendering an aluminum base metal surface resistant to water staining is provided which comprises providing an aluminum base metal surface and applying a stain resistant coating to the aluminum base metal surface, with the stain resistant coating containing a water soluble molybdate salt and water soluble nitrite compound in an amount sufficient to render the aluminum base metal surface resistant to water staining. An aluminum base metal article of manufacture which is resistant to water staining is also provided.

Abstract: Rust preventing resin composition comprising a condensate of tannic acid, a phenol and an aldehyde or a ketone formed in the presence of an acid catalyst. The composition may be used as anticorrosive or rust preventing coating compositions.