System for treating metal substrates

Abstract

A system for treating a substrate surface is disclosed. The system includes a conditioner composition and a first pretreatment composition. The conditioner composition includes a hydroxide source, and the first pretreatment composition includes elemental magnesium, an elemental halide, and an oxidizing agent. A method for treating a substrate surface using the conditioner composition and the first pretreatment composition is also disclosed. Substrates treated by the system and method are also disclosed. For example, a system for treating a metal substrate is disclosed, the system including a conditioner composition including a hydroxide source and a first pretreatment composition including elemental magnesium, an elemental halide, and an oxidizing agent.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Patent Application No. 62 / 628,503, filed February 9, 2018, entitled "System For Treating A Metal Substrate," which is incorporated herein by reference in its entirety.

[0002] The present invention relates to a system and method for treating metal substrates. The present invention also relates to coated metal substrates. [Background technology]

[0003] Oxidation and degradation are serious and costly problems for metals used in aerospace, commercial, and civilian industries. To prevent oxidation and degradation of metals used in these applications, an inorganic protective coating can be applied to the metal surface. This inorganic protective coating, also referred to as a pretreatment coating, can be the only coating applied to the metal, or it can be an intermediate coating to which a subsequent coating is applied. Summary of the Invention [Means for solving the problem]

[0004] Disclosed herein is a system for treating a metal substrate that includes a conditioner composition that includes a hydroxide-containing compound and a first pretreatment composition that includes elemental magnesium, an elemental halide, and an oxidizing agent.

[0005] Also disclosed is a method of treating a substrate, the method comprising contacting at least a portion of the substrate with a conditioner composition having a pH greater than 9, and contacting at least the portion of the substrate contacted with the conditioner composition with a first pretreatment composition comprising elemental magnesium, an elemental halide, and an oxidizing agent.

[0006] Also disclosed are substrates obtainable by the system and / or method. [Brief explanation of the drawings]

[0007] [Figure 1] 1A-1D are images of panels treated according to (A) Example 14, (B) Example 15, (C) Example 16, and (D) Example 17 after 1 day of exposure to neutral salt spray in a cabinet operated according to ASTM B117. [Figure 2-1] FIG. 1 shows the (A) average total depth (μm), (B) maximum total depth (μm), and (C) equivalent circle diameter (μm) generated using a Keyence VR3200 3D Measuring Macroscope for panels treated according to Examples 14-17 after 1 day of exposure to neutral salt spray in a cabinet operated according to ASTM B117. [Figure 2-2] Same as above. [Figure 3-1] 1A-1E are images of panels treated according to (A) Example 14, (B) Example 15, (C) Example 16, (D) Example 17, and (E) Example 7 after 7 days of exposure to neutral salt spray in a cabinet operated according to ASTM B117. [Figure 3-2] Same as above. [Figure 4A] 1A and 1B are XPS depth profiles of a substrate cleaned by solvent wiping only and a substrate treated according to Example 14 (A), and a substrate treated according to Example 15 (B). [Figure 4B] Same as above. DETAILED DESCRIPTION OF THE INVENTION

[0008] For purposes of the following detailed description, it should be understood that the invention may contemplate various alternative modifications and step sequences unless expressly stated to the contrary. Moreover, other than in any operating examples, or where otherwise indicated, all numbers expressing values, amounts, percentages, ranges, subranges, and fractions, etc., may be read as if preceded by the word "about," even if such term is not expressly stated. Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and appended claims are approximations that may vary depending upon the desired properties obtained by the present invention. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should be construed in light of at least the number of reported significant digits and by applying ordinary rounding techniques. Where closed or open-ended numerical ranges are recited herein, all numbers, values, amounts, percentages, subranges, and fractions within or subsumed within the numerical ranges are to be considered specifically included in and belonging to the original disclosure of this application, as if those numbers, values, amounts, percentages, subranges, and fractions were expressly written out in their entirety.

[0009] Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values ​​set forth in the specific examples are reported as precisely as possible. However, any numerical value inherently contains certain errors necessarily resulting from the standard variation found in their respective testing measurements.

[0010] As used herein, unless otherwise indicated, plural terms can encompass their singular counterparts, and vice versa. For example, although this specification refers to "a" pretreatment composition, "a" sealing composition, and "an" oxidizing agent, combinations (i.e., multiples) of those components can be used. Additionally, although "and / or" may be explicitly used in certain instances herein, unless otherwise stated, the use of "or" means "and / or."

[0011] As used herein, "including," "containing," and similar terms are understood to be synonymous with "comprising" in the context of this application and, therefore, are open-ended and do not exclude the presence of additional, undescribed and / or unenumerated elements, materials, components, and / or method steps. As used herein, "consisting of" is understood in the context of this application to exclude the presence of any unspecified elements, components, and / or method steps. As used herein, "consisting essentially of" is understood in the context of this application to include specified elements, materials, components, and / or method steps, "which do not materially affect the basic and novel characteristic(s)" of what is being described.

[0012] Unless otherwise disclosed herein, the term "substantially free," when used in reference to the absence of a particular material, means that such material, if present at all in the composition, in a bath containing the composition, and / or in a layer formed from and comprising the composition, is present only in trace amounts of 5 ppm or less based on the total weight of the composition or layer(s), as the case may be, excluding any amounts of such material that may be present or derived as a result of dissolution of the drug-in, substrate(s), and / or device. Unless otherwise disclosed herein, the term "essentially free," when used in reference to the absence of a particular material, means that such material, if present at all in the composition, in a bath containing the composition, and / or in a layer formed from and comprising the composition, is present only in trace amounts of 1 ppm or less based on the total weight of the composition or layer(s), as the case may be. Unless otherwise disclosed herein, the term "completely free," when used in reference to the absence of a particular material, means that if any such material is present in the composition, in a bath containing the composition, and / or in a layer formed from and including the composition, then the composition, the bath containing the composition, and / or the layer formed from and including the composition is absent (i.e., the composition, the bath containing the composition, and / or the layer formed from and including the composition contains 0 ppm of such material).

[0013] As used herein, the terms "on," "upon," "applied on," "applied onto," "formed on," "deposited on," and "deposited onto" mean formed on, superimposed on, deposited on, and / or provided on a surface, but not necessarily in contact with the surface. For example, a coating layer "formed over" a substrate does not exclude the presence of one or more other intervening coating layers of the same or different composition located between the formed coating layer and the substrate.

[0014] As used herein, "salt" refers to an ionic compound composed of a metal cation and a non-metal anion, with an overall charge of zero. Salts can be hydrated or anhydrous.

[0015] As used herein, "aqueous composition" refers to a solution or dispersion in a medium that primarily contains water. For example, the aqueous medium may contain water in an amount greater than 50% by weight, or greater than 70% by weight, or greater than 80% by weight, or greater than 90% by weight, or greater than 95% by weight, based on the total weight of the medium. The aqueous medium may, for example, consist essentially of water.

[0016] As used herein, "conditioner composition" refers to a composition, i.e., a solution or dispersion, that, upon contact with a substrate surface, can improve the performance of a subsequently applied pretreatment composition.

[0017] As used herein, "pretreatment composition" refers to a composition that is capable of reacting with and chemically altering a substrate surface to form a film that bonds thereto and provides corrosion protection.

[0018] As used herein, "pretreatment bath" refers to an aqueous bath that contains a pretreatment composition and may contain components that are by-products of the process of contacting a substrate with the pretreatment composition.

[0019] As used herein, "sealing composition" refers to a composition, e.g., a solution or dispersion, that affects a substrate surface or a material deposited on a substrate surface to change the physical and / or chemical properties of the substrate surface (i.e., the composition confers corrosion protection).

[0020] As used herein, the term "Group IA metal" or "Group IA element" refers to an element in Group IA of the CAS version of the Periodic Table of the Elements as shown, for example, in the Handbook of Chemistry and Physics, 63rd Edition (1983), which corresponds to Group 1 in the actual IUPAC numbering.

[0021] As used herein, the term "Group IA metal compound" refers to a compound that includes at least one element from Group IA of the CAS version of the Periodic Table of the Elements.

[0022] As used herein, the terms "Group IIIB metals" or "Group IIIB elements" refer to, for example, yttrium and scandium in the CAS version of the Periodic Table of the Elements as set forth in the Handbook of Chemistry and Physics, 63rd Edition (1983), which corresponds to Group 3 in the actual IUPAC numbering. For clarity, "Group IIIB metals" specifically excludes the lanthanide series elements.

[0023] As used herein, the term "Group IIIB metal compound" refers to a compound that includes at least one element from Group IIIB of the CAS version of the Periodic Table of the Elements, as defined above.

[0024] As used herein, the terms "Group IVB metal" or "Group IVB element" refer to elements in Group IVB of the CAS version of the Periodic Table of the Elements as shown, for example, in the Handbook of Chemistry and Physics, 63rd Edition (1983), which corresponds to Group 4 in the actual IUPAC numbering.

[0025] As used herein, the term "Group IVB metal compound" refers to a compound that includes at least one element from Group IVB of the CAS version of the Periodic Table of the Elements.

[0026] As used herein, the term "Group VB metal" or "Group VB element" refers to an element in Group VB of the CAS version of the Periodic Table of the Elements as shown, for example, in the Handbook of Chemistry and Physics, 63rd Edition (1983), which corresponds to Group 5 in the actual IUPAC numbering.

[0027] As used herein, the term "Group VB metal compound" refers to a compound that includes at least one element from Group VB of the CAS version of the Periodic Table of the Elements.

[0028] As used herein, the term "Group VIB metal" or "Group VIB element" refers to an element in Group VIB of the CAS version of the Periodic Table of the Elements as shown, for example, in the Handbook of Chemistry and Physics, 63rd Edition (1983), which corresponds to Group 6 in the actual IUPAC numbering.

[0029] As used herein, the term "Group VIB metal compound" refers to a compound that includes at least one element from Group VIB of the CAS version of the Periodic Table of the Elements.

[0030] As used herein, the term "lanthanide series elements" refers to elements 57-71 of the CAS version of the Periodic Table of the Elements, including elemental versions of the lanthanide series elements. In embodiments, the lanthanide series elements can have both +3 and +4 common oxidation states, hereinafter referred to as the +3 / +4 oxidation states.

[0031] As used herein, the term "lanthanide compound" refers to a compound that includes at least one of elements 57-71 of the CAS version of the Periodic Table of the Elements.

[0032] As used herein, the term "halogen" refers to any of fluorine, chlorine, bromine, iodine, and astatine in the CAS version of the Periodic Table of the Elements, which corresponds to Group VIIA of the Periodic Table of the Elements.

[0033] As used herein, the term "halide" refers to a compound that contains at least one halogen.

[0034] As used herein, the term "aluminum," when used in reference to a substrate, refers to substrates made from or including aluminum and / or aluminum alloys, as well as clad aluminum substrates.

[0035] As used herein, the term "oxidizing agent," when used with respect to a component of a pretreatment composition, refers to a chemical capable of oxidizing at least one of a metal present in a substrate contacted by the pretreatment composition, a metal cation present in the pretreatment composition, and / or a metal-complexing agent present in the pretreatment composition. As used herein with respect to an "oxidizing agent," the phrase "capable of oxidizing" means capable of removing electrons from atoms or molecules present in the substrate or pretreatment composition, as the case may be, thereby reducing the electron count of such atoms or molecules.

[0036] Pitting corrosion is the localized formation of corrosion that produces cavities or holes in a substrate. As used herein, the term "pit" refers to such cavities or holes resulting from pitting corrosion, characterized by the following characteristics when viewed with the naked eye: (1) a rounded, elongated, or irregular appearance when viewed perpendicular to the test panel surface; (2) a "comet tail," line, or "halo" (i.e., surface discoloration) emanating from the pit cavity; and (3) the presence of corrosion by-products (e.g., white, gray, or black granular, powdery, or amorphous material) within or immediately surrounding the pit. Surface cavities or holes observed with the naked eye must exhibit at least two of the above characteristics to be considered corrosion pits. Surface cavities or holes exhibiting only one of these characteristics may require additional analysis, e.g., by macroscopy, using established minimum parameters of surface area and depth, before being classified as corrosion pits, examples of which are described in detail below. Unless otherwise indicated, the term "pits" as used herein refers to those pits that are observable with the naked eye.

[0037] As used herein, the term "corrosion" refers to the presence of corrosion by-products (e.g., white, gray, or black granular, powdery, or amorphous material) within or immediately surrounding a pit.

[0038] As used herein, a substrate with fewer pits (whether counted by the naked eye or by using an additional analytical tool such as a macroscope) will have better corrosion performance than a substrate with more pits (counted by the same method), and a substrate with >100 pits will have better corrosion performance than a substrate with 15% or more surface corrosion. Increasing % surface corrosion indicates decreased corrosion performance.

[0039] Unless otherwise disclosed herein, as used herein, "total composition weight," "total composition weight," or similar terms refer to the total weight of all components present in the respective composition, including any carriers and solvents.

[0040] Disclosed herein in accordance with the present invention is a system for treating a substrate, comprising, consisting essentially of, or consisting of a conditioner composition and a first pretreatment composition. The conditioner composition may comprise, consist essentially of, or consist of a hydroxide-containing compound. The first pretreatment composition may comprise, consist essentially of, or consist of elemental magnesium, elemental halogen, and an oxidizing agent. The system of the present invention may comprise, consist essentially of, or consist of the conditioner composition and the first pretreatment composition, as well as a cleaning composition, an oxygen scavenger, a second pretreatment composition, and / or a sealing composition.

[0041] Also disclosed herein is a method for treating a substrate, comprising, consisting essentially of, or consisting of contacting at least a portion of the substrate surface with a conditioner composition, as described above, and contacting at least a portion of the substrate contacted with the conditioner composition with a first pretreatment composition. The conditioner composition may comprise, consist essentially of, or consist of a hydroxide-containing compound. The first treatment composition may comprise, consist essentially of, or consist of elemental magnesium, elemental halogen, and an oxidizing agent. The method of the present invention may comprise, consist essentially of, or consist of contacting at least a portion of the substrate surface with the conditioner composition and the first pretreatment composition, and contacting at least a portion of the substrate surface with a cleaning composition, an oxygen scavenger, a second pretreatment composition, and / or a sealing composition.

[0042] As described herein, a substrate treated with the system and / or method of the present invention can comprise, consist essentially of, or consist of a film or layer formed from a first pretreatment composition. Optionally, the substrate can further comprise, consist essentially of, or consist of a film or layer formed from a second pretreatment composition and / or a film or layer formed from a sealing composition.

[0043] Suitable substrates that can be used in the present invention include metal substrates, metal alloy substrates, and / or metallized substrates such as nickel-plated plastic. The metal or metal alloy can include or be steel, aluminum, zinc, nickel, and / or magnesium. For example, the steel substrate can be cold-rolled steel, hot-rolled steel, electrogalvanized steel, and / or hot-dip galvanized steel. Aluminum alloys of the 1XXX, 2XXX, 3XXX, 4XXX, 5XXX, 6XXX, or 7XXX series, as well as clad aluminum alloys, can also be used as substrates. The aluminum alloy can contain 0.01% to 10% copper by weight. The aluminum alloys to be processed can also include cast aluminum alloys, such as 1XX.X, 2XX.X, 3XX.X, 4XX.X, 5XX.X, 6XX.X, 7XX.X, 8XX.X, or 9XX.X (e.g., A356.0). Magnesium alloys of the AZ31B, AZ91C, AM60B, or EV31A series can also be used as the substrate. Substrates used in the present invention can also include titanium and / or titanium alloys, zinc and / or zinc alloys, and / or nickel and / or nickel alloys. The substrate can include a vehicle body (e.g., but not limited to, doors, body panels, trunk deck lids, roof panels, hoods, roofs and / or stringers, rivets, landing gear components, and / or skins used on aircraft) and / or portions of a vehicle, such as a vehicle frame. As used herein, "vehicle" or variations thereof include, but are not limited to, civilian, commercial, and military aircraft, and / or land vehicles, such as cars, motorcycles, and / or trucks.

[0044] As described above, the system of the present invention includes a conditioner composition. The conditioner composition may include, for example, a hydroxide-containing compound. The hydroxide-containing compound may be provided as any basic material, including, but not limited to, a water-soluble and / or water-dispersible base such as sodium hydroxide, potassium hydroxide, ammonium hydroxide, or a mixture thereof.

[0045] The hydroxide-containing compound of the conditioner composition may further include a cation, such as a Group I metal cation, that may be suitable for forming a salt with the hydroxide anion. Non-limiting examples of such Group I metal cations are lithium, sodium, potassium, or combinations thereof.

[0046] The conditioner composition can have a pH of at least 9.0, e.g., at least 12, and can be 13.5 or less, e.g., 13.0 or less. The conditioner composition can have a pH of 9.0 to 13.5, e.g., 12.0 to 13.0. The pH of the conditioner composition can be adjusted, for example, using any acid and / or base as needed. The pH of the conditioner composition can be maintained by the inclusion of an acidic material, including a water-soluble and / or water-dispersible acid, such as nitric acid, sulfuric acid, and / or phosphoric acid. The pH of the conditioner composition can be maintained by the inclusion of a basic material, including a water-soluble and / or water-dispersible base, e.g., sodium hydroxide, sodium carbonate, potassium hydroxide, ammonium hydroxide, ammonia, and / or an amine, e.g., triethylamine, methylethylamine, or a mixture thereof.

[0047] The conditioner composition can comprise an aqueous medium, and optionally can comprise other materials such as nonionic surfactants and adjuvants.In the aqueous medium, water-dispersible organic solvents can be present, for example, alcohols having up to about 8 carbon atoms, such as methanol, isopropanol, or glycol ethers, for example, monoalkyl ethers, such as ethylene glycol, diethylene glycol, or propylene glycol.When present, the water-dispersible organic solvents are typically used in an amount of up to about 10 volume percent, based on the total volume of the aqueous medium.

[0048] Other optional materials included in the conditioner composition include surfactants that function as antifoaming agents or substrate wetting agents. Anionic, cationic, amphoteric, and / or nonionic surfactants may be used. Antifoaming surfactants can optionally be present at a level of up to 1 weight percent, e.g., up to 0.1 weight percent, based on the total weight of the pretreatment composition, and wetting agents can typically be present at a level of up to 2 weight percent, e.g., up to 0.5 weight percent.

[0049] The conditioner composition may include a carrier, often an aqueous medium, such that the composition is in the form of a solution or dispersion of hydroxide anions in the carrier. The solution or dispersion may be contacted with the substrate by any of a variety of known techniques, such as dipping or immersion, spraying, intermittent spraying, dipping followed by spraying, brushing, or roll coating. The solution or dispersion may be at a temperature ranging from 40°F to 160°F, e.g., 60°F to 110°F, e.g., 70°F to 90°F, when applied to the metal substrate. For example, the conditioning process may be carried out at ambient or room temperature. The contact time may be from 5 seconds to 15 minutes, e.g., 4 minutes to 10 minutes.

[0050] According to the present invention, after contact with the conditioner composition, the substrate may optionally be air-dried at room temperature, or may be dried with hot air by briefly exposing the substrate to high temperatures, for example, by using an air knife to flash off water, for example, by drying the substrate in an oven at 15°C to 100°C, e.g., 20°C to 90°C, or for example, at 70°C for 10 minutes, for example, in a heater assembly using infrared heat, or by passing the substrate between squeegee rolls. After contact with the conditioner composition, the substrate may optionally be rinsed with tap water, deionized water, and / or an aqueous solution of rinse liquid to remove any residue, and then optionally dried, for example, air-dried or with hot air as described above. Alternatively, at least a portion of the substrate surface may be wet (i.e., not dry) when contacted with the subsequent treatment step.

[0051] The system also includes a first pretreatment composition, which may include elemental magnesium, an elemental halogen, and an oxidizing agent.

[0052] The elemental magnesium can be present in the first pretreatment composition in an amount of at least 500 ppm (as magnesium cations), e.g., at least 1000 ppm, e.g., at least 1300 ppm, based on the total weight of the first pretreatment composition, and can be present in an amount of 6000 ppm or less (as magnesium cations), e.g., 3000 ppm or less, e.g., 1700 ppm or less, based on the total weight of the first pretreatment composition. The elemental magnesium can be present in the first pretreatment composition in an amount of 500 ppm to 6000 ppm (as magnesium cations), e.g., 1000 ppm to 3000 ppm, e.g., 1300 ppm to 1700 ppm, based on the total weight of the first pretreatment composition.

[0053] The first pretreatment composition may further include anions that may be suitable for forming salts with elemental magnesium, such as halogens, sulfates, nitrates, acetates, and the like.

[0054] The first pretreatment composition may further comprise a halogen element. The halogen element may be present in the first pretreatment composition in an amount of at least 1500 ppm (as halogen anion), e.g., at least 3000 ppm, e.g., at least 4,000 ppm, based on the total weight of the first pretreatment composition, and may be present in an amount of 40,000 ppm or less (as halogen anion), e.g., 18,000 ppm or less, e.g., 11,000 ppm or less, based on the total weight of the first pretreatment composition. The halogen element may be present in the first pretreatment composition in an amount of 1500 ppm to 40,000 ppm (as halogen anion), e.g., 3000 ppm to 18,000 ppm, e.g., 4000 ppm to 11,000 ppm, based on the total weight of the first pretreatment composition.

[0055] The first pretreatment composition may further include cations suitable for forming salts with halogen elements, such as metal cations of the lanthanide series elements, metal cations of Group IA metals, Group IIA metals, Group IIIB metals, Group IVB metals, Group VB metals, Group VIB metals, Group VIIB metals, and / or Group XII metals, or combinations thereof.

[0056] The halogen element can be the same as or different from the halogen that forms a salt with the magnesium cation described above. For example, the magnesium cation and halide anion can be derived from a single source, or alternatively, the magnesium cation and halide anion can be derived from different sources.

[0057] The first pretreatment composition may further comprise an oxidizing agent, non-limiting examples of which include peroxide, persulfate, perchlorate, hypochlorite, nitric acid, sparged oxygen, bromate, peroxybenzoate, ozone, or a combination thereof.

[0058] The oxidizing agent can be present in an amount of at least 100 ppm, e.g., at least 500 ppm, e.g., at least 750 ppm, based on the total weight of the first pretreatment composition, and can be present in an amount of 3000 ppm or less, e.g., 2000 ppm or less, e.g., 1000 ppm or less, based on the total weight of the first pretreatment composition. The oxidizing agent can be present in the first pretreatment composition in an amount of 100 ppm to 3000 ppm, e.g., 500 ppm to 2000 ppm, e.g., 750 ppm to 1000 ppm, based on the total weight of the first pretreatment composition.

[0059] The first pretreatment composition can have a pH of at least 1.0, e.g., at least 2.8, e.g., at least 4.0, e.g., at least 5.0, and can have a pH of 10.0 or less, e.g., 9.0 or less, e.g., 7.0 or less. The first pretreatment composition can have a pH of 1.0 to 7.0, e.g., 2.8 to 6.5, e.g., 4.0 to 7.0, e.g., 4.0 to 9.0, e.g., 7.0 to 10.0. However, the pH of the first pretreatment composition can vary based on the solubility range of the magnesium cation and the temperature of the first pretreatment composition. The pH of the first pretreatment composition can be adjusted as needed, for example, using any acid and / or base. The pH of the first pretreatment composition can be maintained by the inclusion of an acidic material, including water-soluble and / or water-dispersible acids, such as nitric acid, sulfuric acid, and / or phosphoric acid. The pH of the first pretreatment composition can be maintained by the inclusion of a basic material including a water-soluble and / or water-dispersible base, e.g., sodium hydroxide, sodium carbonate, potassium hydroxide, ammonium hydroxide, ammonia, and / or an amine, e.g., triethylamine, methylethylamine, or mixtures thereof.

[0060] The system of the present invention may optionally include a second pretreatment composition containing at least one rare earth element. Optionally, the second pretreatment composition may include a lanthanide series element, such as cerium, praseodymium, terbium, or a combination thereof. For example, the lanthanide series element used in the second pretreatment composition may be a compound of cerium, praseodymium, terbium, or a combination thereof. Suitable compounds of cerium include, but are not limited to, cerium nitrate, cerium halides, or a combination thereof. Optionally, the second pretreatment composition may include a Group IIIB element, such as yttrium, scandium, or a combination thereof. For example, the Group IIIB element used in the second pretreatment composition may be a compound of yttrium, scandium, or a mixture thereof. Suitable yttrium compounds include, but are not limited to, yttrium halides. In one example, the second pretreatment composition includes a lanthanide series element and a Group IIIB element.

[0061] The rare earth element can be present in the second pretreatment composition in an amount of at least 5 ppm (as rare earth cations), e.g., at least 150 ppm, e.g., at least 300 ppm, based on the total weight of the second pretreatment composition, and can be present in the second pretreatment composition in an amount of 25,000 ppm or less (as rare earth cations), e.g., 12,500 ppm or less, e.g., 10,000 ppm or less, based on the total weight of the second pretreatment composition. The rare earth element can be present in the second pretreatment composition in an amount of 5 ppm to 25,000 ppm (as rare earth cations), e.g., 150 ppm to 12,500 ppm, e.g., 300 ppm to 10,000 ppm, based on the total weight of the second pretreatment composition.

[0062] The second pretreatment composition may further include anions that may be suitable for forming salts with rare earth elements, such as halogens, nitrates, sulfates, phosphates, silicates (orthosilicates and metasilicates), carbonates, acetates, hydroxides, fluorides, and the like.

[0063] Anions suitable for forming salts with rare earth elements can be present in the second pretreatment composition in an amount of at least 2 ppm (calculated as anion), e.g., at least 50 ppm, e.g., at least 150 ppm, e.g., at least 500 ppm, based on the total weight of the second pretreatment composition, and can be present in an amount of 25,000 ppm or less (calculated as anion), e.g., 18,500 ppm or less, e.g., 5000 ppm or less, e.g., 2500 ppm or less, based on the total weight of the second pretreatment composition. For example, the anions can be present in the second pretreatment composition in an amount of 5 ppm to 25,000 ppm (calculated as anion), e.g., 50 ppm to 18,500 ppm, e.g., 150 ppm to 4000, e.g., 500 ppm to 2000 ppm, based on the total weight of the second pretreatment composition. For example, the anion can be present in the second pretreatment composition in an amount of 2 ppm to 10,000 ppm (calculated as the anion), e.g., 50 ppm to 5000 ppm, e.g., 250 ppm to 2500 ppm, based on the total weight of the second pretreatment composition.

[0064] The second pretreatment composition may optionally include an oxidizing agent, non-limiting examples of which include peroxide, persulfate, perchlorate, hypochlorite, nitric acid, sparged oxygen, bromate, peroxybenzoate, ozone, or a combination thereof.

[0065] The oxidizing agent, if present at all, can be present in an amount of at least 100 ppm, e.g., at least 500 ppm, based on the total weight of the second pretreatment composition, and optionally can be present in an amount of 13,000 ppm or less, e.g., 3000 ppm or less, based on the total weight of the second pretreatment composition. In some cases, the oxidizing agent, if present at all, can be present in the second pretreatment composition in an amount of 100 ppm to 13,000 ppm, e.g., 500 ppm to 3000 ppm, based on the total weight of the second pretreatment composition.

[0066] According to the present invention, the pH of the second pretreatment composition can be at least 1.0, e.g., at least 3.0, and can be 4.5 or less, e.g., 4.0 or less. The pH of the second pretreatment composition can be 1.0 to 4.5, e.g., 3 to 4, and can be adjusted as needed, for example, using any acid and / or base. The pH of the second pretreatment composition can be maintained by the inclusion of an acidic material, including a water-soluble and / or water-dispersible acid, such as nitric acid, sulfuric acid, and / or phosphoric acid. The pH of the second pretreatment composition can be maintained by the inclusion of a basic material, including a water-soluble and / or water-dispersible base, e.g., sodium hydroxide, sodium carbonate, potassium hydroxide, ammonium hydroxide, ammonia, and / or an amine, e.g., triethylamine, methylethylamine, or a mixture thereof.

[0067] Optionally, the first and / or second pretreatment compositions can exclude chromium or chromium-containing compounds. As used herein, the term "chromium-containing compounds" refers to materials containing hexavalent chromium. Non-limiting examples of such materials include chromic acid, chromium trioxide, chromic anhydride, dichromates such as ammonium dichromate, sodium dichromate, potassium dichromate, and calcium dichromate, barium dichromate, magnesium dichromate, zinc dichromate, cadmium dichromate, and strontium dichromate. When the pretreatment composition and / or coating or layer formed from the pretreatment composition is substantially, essentially, or completely free of chromium, it includes any form of chromium, such as, but not limited to, the hexavalent chromium-containing compounds listed above.

[0068] Thus, optionally, the first and / or second pretreatment compositions and / or coatings or layers deposited therefrom may be substantially free, essentially free, and / or completely free of any one or more of the elements or compounds listed in the preceding paragraph. A pretreatment composition and / or coating or layer formed therefrom that is substantially free of chromium or its derivatives means that chromium or its derivatives are not intentionally added but may be present in trace amounts due to, for example, impurities or unavoidable contamination from the environment. In other words, the amount of material is small enough not to affect the properties of the pretreatment composition; in the case of chromium, this may further include the element or its compound not being present in the pretreatment composition and / or coating or layer formed therefrom at levels that are environmentally unfriendly. The term "substantially free" means that the pretreatment composition and / or coating or layer formed therefrom, if present, contains less than 10 ppm of any or all of the elements or compounds listed in the preceding paragraph, based on the total weight of the composition or layer, respectively. The term "essentially free" means that the pretreatment composition and / or coating or layer formed therefrom, if present, contains less than 1 ppm of any or all of the elements or compounds listed in the preceding paragraph. The term "completely free" means that the pretreatment composition and / or coating or layer formed therefrom, if present, contains less than 1 ppb of any or all of the elements or compounds listed in the preceding paragraph.

[0069] According to the present invention, the first and / or second pretreatment compositions can, in some cases, eliminate the formation of sludge, e.g., aluminum phosphate, iron phosphate, and / or zinc phosphate, that is formed when using treatments based on phosphate ions or phosphate-containing compounds, and / or zinc phosphate. As used herein, "phosphate-containing compounds" include compounds containing the element phosphorus, such as orthophosphates, pyrophosphates, metaphosphates, tripolyphosphates, and organophosphates, and may include monovalent, divalent, or trivalent cations, such as, but not limited to, sodium, potassium, calcium, zinc, nickel, manganese, aluminum, and / or iron. When the pretreatment composition and / or layer or coating comprising it is substantially free, essentially free, or completely free of phosphate, it includes phosphate ions or phosphate-containing compounds in any form.

[0070] Thus, the first and / or second pretreatment compositions and / or layers deposited therefrom may be substantially free, or in some cases essentially free, or in some cases completely free, of any one or more of the ions or compounds listed above. A pretreatment composition and / or layer deposited therefrom being substantially free of phosphate means that phosphate ions or phosphate-containing compounds are not intentionally added but may be present in trace amounts due to, for example, impurities or unavoidable environmental contamination. In other words, the amount of material is so small that it does not affect the properties of the composition, which may further include the absence of phosphates in the pretreatment composition and / or layers deposited therefrom at levels such that they pose a burden to the environment. The term "substantially free" means that the pretreatment composition and / or layers deposited therefrom, if present, contain less than 5 ppm of any or all of the phosphate anions or compounds listed above, based on the total weight of the composition or layer, respectively. The term "essentially free" means that the pretreatment composition and / or layer comprising the pretreatment composition contains less than 1 ppm of any or all of the phosphate anions or compounds listed in the preceding paragraph. The term "completely free" means that the pretreatment composition and / or layer comprising the pretreatment composition, if present, contains less than 1 ppb of any or all of the phosphate anions or compounds listed in the preceding paragraph.

[0071] The first and / or second pretreatment compositions can include an aqueous medium, and can optionally contain other materials, such as nonionic surfactants and adjuvants, conventionally used in the art of pretreatment compositions. In the aqueous medium, a water-dispersible organic solvent, such as an alcohol having up to about 8 carbon atoms, such as methanol or isopropanol, or a glycol ether, such as a monoalkyl ether, such as ethylene glycol, diethylene glycol, or propylene glycol, can be present. When present, the water-dispersible organic solvent is typically used in an amount of up to about 10 volume percent, based on the total volume of the aqueous medium.

[0072] Other optional materials included in the first and / or second pretreatment compositions include surfactants that function as antifoaming agents or substrate wetting agents. Anionic, cationic, amphoteric, and / or nonionic surfactants may be used. Antifoaming surfactants can optionally be present at levels of up to 1 weight percent, e.g., up to 0.1 weight percent, based on the total weight of the pretreatment composition, and wetting agents can typically be present at levels of up to 2 weight percent, e.g., up to 0.5 weight percent.

[0073] Optionally, the first and / or second pretreatment compositions and / or films deposited or formed therefrom may further comprise silicon in an amount of at least 10 ppm, e.g., at least 20 ppm, e.g., at least 50 ppm, based on the total weight of the pretreatment composition. The first and / or second pretreatment compositions and / or films deposited or formed therefrom may comprise silicon in an amount of less than 500 ppm, e.g., less than 250 ppm, e.g., less than 100 ppm, based on the total weight of the pretreatment composition. The first and / or second pretreatment compositions and / or films deposited or formed therefrom may comprise silicon in an amount of 10 ppm to 500 ppm, e.g., 20 ppm to 250 ppm, e.g., 50 ppm to 100 ppm, based on the total weight of the pretreatment composition. Alternatively, the first and / or second pretreatment compositions of the present invention and / or films deposited or formed therefrom may be substantially free of silicon, or completely free of silicon.

[0074] The first and / or second pretreatment compositions may include a carrier, often an aqueous medium, such that the composition is in the form of a solution or dispersion of metal cations and / or metal cation-containing compounds in the carrier. The solution or dispersion may be contacted with the substrate by any of a variety of known techniques, such as dipping or immersion, spraying, intermittent spraying, dipping followed by spraying, brushing, or roll coating. The solution or dispersion may be at a temperature ranging from 40°F to 160°F, e.g., 60°F to 110°F, e.g., 70°F to 90°F, when applied to the metal substrate. For example, the pretreatment process may be carried out at ambient or room temperature. The contact time may be from 5 seconds to 15 minutes, e.g., 4 minutes to 10 minutes.

[0075] According to the present invention, after contact with the first and / or second pretreatment compositions, the substrate may optionally be air-dried at room temperature, or may be dried with hot air by briefly exposing the substrate to high temperatures, e.g., by using an air knife to flash off water, e.g., in an oven at 15°C to 100°C, e.g., 20°C to 90°C, or by drying the substrate for 10 minutes, e.g., at 70°C, in a heater assembly using infrared heating, or by passing the substrate between squeegee rolls. After contact with the pretreatment compositions, the substrate may optionally be rinsed with tap water, deionized water, and / or an aqueous solution of rinse liquid to remove any residue, and then optionally dried, e.g., air-dried or with hot air as described above. Alternatively, at least a portion of the substrate surface may be wet (i.e., not dry) when contacted with the subsequent treatment step.

[0076] At least a portion of the substrate surface may be cleaned and / or deoxidized to remove grease, dirt, and / or other foreign matter prior to contacting at least a portion of the substrate surface with the above-described conditioner composition. At least a portion of the substrate surface may be cleaned by physical and / or chemical means, such as mechanically abrading the surface and / or cleaning / degreasing the surface with commercially available alkaline or acidic cleaners well known to those skilled in the art. Examples of alkaline cleaners suitable for use in the present invention include Chemkleen™ 166HP, 166M / C, 177, 490MX, 2010LP, and Surface Prep 1 (SP1), Ultrax 32, Ultrax 97, Ultrax 29, and Ultrax 92D, each of which is commercially available from PPG Industries, Inc. (Cleveland, Ohio), as well as any of the DFM series, RECC 1001, and 88X 1002 cleaners commercially available from PRC-DeSoto International (Sylmar, Calif.), and Turco 4215-NCLT and Ridolene commercially available from Henkel Technologies (Madison Heights, Mich.). Such cleaners are often preceded or followed by a water rinse, such as tap water, distilled water, or a combination thereof.

[0077] As described above, at least a portion of the substrate surface can be mechanically and / or chemically deoxidized. As used herein, the term "deoxidize" refers to at least partial removal of the oxide layer found on the surface of the substrate. When used herein with reference to oxide layer removal, the term "at least partial" refers to removal determined using a number of analytical techniques, including, but not limited to, XPS (x-ray photoelectron spectroscopy) depth profiling or TEM (transmission electron microscopy). For example, transmission electron microscope (TEM) images can be captured from the panel by any protocol known to those skilled in the art, including the use of an FEI Helios Nanolab 660 dual-beam focused ion beam (FIB) using the "in situ lift-out" technique (RM Langford, "In situ lift-out using a FIB-SEM system," Micron v. 35, pp. 607-611, 2004). A gold layer (Au) and then a carbon layer (C) can be deposited on the surface of the sample using the FIB to prevent damage during subsequent Ga+ ion beam milling. Thin sections approximately 5 microns wide and 5 microns deep can be milled from the surface of the sample using a 30 kV ion beam and attached in situ to a TEM grid using a micromanipulator. The sections can then be further thinned with the ion beam to a final thickness of approximately 100 nm. An ion beam energy of 2 kV can be used for final surface cleaning. TEM and scanning transmission electron microscopy (STEM) can be performed, for example, using an FEI Talos F200X field emission TEM at an acceleration voltage of 200 kV. The magnification of the microscope can be calibrated using a two-dimensional cross grating replica standard from Agar Scientific. (Cross Grating Replica, AGS106, diffraction line grating spacing 462.9 nm, http: / / www.agarscientific.com / diffraction-grating-replicas.html).HAADF-STEM (High Angle Annular Dark Field) images are collected from the sample, primarily showing mass contrast that is roughly proportional to the square of the atomic numbers of the elements present.

[0078] Suitable oxygen scavengers will be familiar to those skilled in the art. A typical mechanical oxygen scavenger can be, for example, a uniform roughening of the substrate surface by using a scouring pad or a cleaning pad. Typical chemical oxygen scavengers include, for example, acid-based oxygen scavengers such as phosphoric acid, nitric acid, fluoroboric acid, sulfuric acid, chromic acid, hydrofluoric acid, and ammonium bifluoride, or Amchem 7 / 17 oxygen scavengers (available from Henkel Technologies, Madison Heights, MI), OAKITE DEOXIDIZER LNC (commercially available from Chemetall), TURCO DEOXIDIZER 6 (commercially available from Henkel), or combinations thereof. Chemical oxygen scavengers often include a carrier, often an aqueous medium, so that the oxygen scavengers can be in the form of a solution or dispersion in the carrier, in which case the solution or dispersion can be contacted with the substrate by any of a variety of known techniques, such as dipping or immersion, spraying, intermittent spraying, dipping followed by spraying, brushing, or roll coating. One skilled in the art will select the temperature range of the solution or dispersion when applied to the metal substrate based on the etching rate, for example, at temperatures ranging from 50°F to 150°F (10°C to 66°C), for example, from 70°F to 130°F (21°C to 54°C), for example, from 80°F to 120°F (27°C to 49°C). The contact time can be from 30 seconds to 20 minutes, for example, from 1 minute to 15 minutes, for example, from 90 seconds to 12 minutes, for example, from 3 minutes to 9 minutes.

[0079] Following the cleaning and / or deoxidation step(s), the substrate can optionally be rinsed with tap water, deionized water, and / or an aqueous solution of rinse to remove any residue. The wet substrate surface may be treated with a pretreatment composition (above) and / or a sealing composition (below), or the substrate may be dried, e.g., air-dried, by flashing off the water by briefly exposing it to an elevated temperature, e.g., 15°C to 100°C, e.g., 20°C to 90°C, e.g., by using an air knife, or by passing the substrate between squeegee rolls, e.g., at 70°C for 10 minutes.

[0080] As described above, the system of the present invention may optionally include a sealing composition. The sealing composition may include elemental lithium. The elemental lithium may be in the form of a lithium salt. Furthermore, the sealing composition may also further include at least one Group IA, VB, and / or VIB element other than lithium. The at least one Group IA, VB, and / or VIB element other than lithium may be in the form of a salt. Non-limiting examples of anions suitable for forming salts with lithium, Group IA, VB, and / or VIB elements other than lithium include carbonates, hydroxides, nitrates, halogens, sulfates, phosphates, and silicates (e.g., orthosilicates and metasilicates). As a result, the metal salts may include carbonates, hydroxides, nitrates, halides, sulfates, phosphates, silicates (e.g., orthosilicates or metasilicates), permanganates, chromates, vanadates, molybdates, and / or perchlorates.

[0081] According to the present invention, the metal salts of the sealing composition (i.e., salts of lithium, Group IA elements other than lithium, Group VB elements, and / or Group VIB elements) may each be present in the sealing composition in an amount of at least 25 ppm, e.g., at least 150 ppm, e.g., at least 500 ppm (calculated as total compounds), based on the total weight of the sealing composition, and in some cases in an amount of 30,000 ppm or less, e.g., 2,000 ppm or less, e.g., 1,750 ppm or less (calculated as total compounds), based on the total weight of the sealing composition. According to the present invention, the metal salts of the sealing composition (i.e., salts of lithium, Group IA elements other than lithium, Group VB elements, and / or Group VIB elements) may each be present in the sealing composition in an amount of 25 ppm to 30,000 ppm, e.g., 150 ppm to 2,000 ppm, e.g., 500 ppm to 1,750 ppm (calculated as total compounds), based on the total weight of the sealing composition.

[0082] According to the present invention, lithium cations, Group IA elements other than lithium, Group VB elements, and Group VIB elements may each be present in the sealing composition in an amount of at least 5 ppm, e.g., at least 50 ppm, e.g., at least 150 ppm, e.g., at least 250 ppm (calculated as cations), based on the total weight of the sealing composition, and in some cases may be present in an amount of 5500 ppm or less, e.g., 1200 ppm or less, e.g., 1000 ppm or less, e.g., 500 ppm or less (calculated as cations), based on the total weight of the sealing composition. Optionally, according to the present invention, lithium cations, Group IA elements other than lithium, Group VB elements, and Group VIB elements may each be present in the sealing composition in an amount of 5 ppm to 5500 ppm, e.g., 50 ppm to 1000 ppm (calculated as cations), e.g., 150 ppm to 500 ppm, based on the total weight of the sealing composition.

[0083] The lithium salt may include an inorganic lithium salt, an organic lithium salt, or a combination thereof. Both the anion and the cation of the lithium salt may be water-soluble. For example, according to the present invention, the lithium salt may have a solubility of at least 1×10 in water at a temperature of 25° C. (K). -11 , e.g., at least 1 x 10 -4 , and in some cases, 5 × 10 +2 The lithium salt may have the following solubility constant: 1×10 in water at a temperature of 25° C. (K; 25° C.). -11 ~5×10 +2 , e.g., 1 x 10 -4 ~5×10 +2 As used herein, "solubility constant" refers to the product of the equilibrium concentrations of ions in a saturated aqueous solution of each lithium salt. Each concentration is raised to the power of the respective ionic coefficient in the equilibrium equation. Solubility constants for various salts can be found in chemistry and physics handbooks.

[0084] The sealing composition may include an oxidizer, such as hydrogen peroxide, persulfates, perchlorates, sparged oxygen, bromates, peroxybenzoates, ozone, or the like, or a combination thereof. For example, the sealing composition may include 0.1% to 15% by weight, e.g., 2% to 10% by weight, e.g., 6% to 8% by weight, of the oxidizer, based on the total weight of the sealing composition. Optionally, the sealing composition may be substantially free, essentially free, or completely free of oxidizer.

[0085] The sealing composition can optionally exclude Group IIA elements or Group IIA metal-containing compounds, including but not limited to calcium. Non-limiting examples of such materials include Group IIA metal hydroxides, Group IIA metal nitrates, Group IIA metal halides, Group IIA metal sulfamates, Group IIA metal sulfates, Group IIA carbonates, and / or Group IIA metal carboxylates. When the sealing composition and / or coating or layer formed from the sealing composition is substantially free, essentially free, or completely free of Group IIA metal cations, it includes any form of Group IIA metal cation, including, but not limited to, the Group IIA metal-containing compounds listed above.

[0086] The sealing composition may optionally exclude chromium or chromium-containing compounds. As used herein, the term "chromium-containing compounds" refers to materials containing hexavalent chromium. Non-limiting examples of such materials include chromic acid, chromium trioxide, chromic anhydride, dichromates such as ammonium dichromate, sodium dichromate, potassium dichromate, and calcium dichromate, barium dichromate, magnesium dichromate, zinc dichromate, cadmium dichromate, and strontium dichromate. When the sealing composition and / or the coating or layer formed from the sealing composition is substantially, essentially, or completely free of chromium, this includes any form of chromium, such as, but not limited to, the hexavalent chromium-containing compounds listed above.

[0087] Thus, optionally, the sealing composition and / or coating or layer formed therefrom may be substantially free, essentially free, and / or completely free of any one or more of the elements or compounds listed in the preceding paragraph. A sealing composition and / or coating or layer formed therefrom that is substantially free of chromium or its derivatives means that chromium or its derivatives are not intentionally added but may be present in trace amounts due to, for example, impurities or unavoidable contamination from the environment. In other words, the amount of material is small enough not to affect the properties of the sealing composition, and in the case of chromium, this may further include that the element or its compound is not present in the sealing composition and / or coating or layer formed therefrom at levels that are environmentally unfriendly. The term "substantially free" means that the sealing composition and / or coating or layer formed therefrom, if present, contains less than 10 ppm of any or all of the elements or compounds listed in the preceding paragraph, based on the total weight of the composition or the total weight of the layer formed therefrom. The term "essentially free" means that the sealing composition and / or coating or layer formed from the sealing composition, if present, contains less than 1 ppm of any or all of the preceding listed elements or compounds. The term "completely free" means that the sealing composition and / or coating or layer formed from the sealing composition, if present, contains less than 1 ppb of any or all of the preceding listed elements or compounds.

[0088] The sealing composition may optionally eliminate the formation of sludge, such as aluminum phosphate, iron phosphate, and / or zinc phosphate, formed when using treatments based on phosphate ions or phosphate-containing compounds, and / or zinc phosphate. As used herein, "phosphate-containing compounds" include compounds containing the element phosphorus, such as orthophosphates, pyrophosphates, metaphosphates, tripolyphosphates, and organophosphates, and may include monovalent, divalent, or trivalent cations, such as, but not limited to, sodium, potassium, calcium, zinc, nickel, manganese, aluminum, and / or iron. When the composition and / or layer or coating comprising it is substantially free, essentially free, or completely free of phosphate, it includes phosphate ions or phosphate-containing compounds in any form.

[0089] Thus, the sealing composition and / or the layer deposited therefrom may be substantially free, or in some cases essentially free, or in some cases completely free of one or more of the ions or compounds listed above. A sealing composition and / or a layer deposited therefrom that is substantially free of phosphate means that phosphate ions or phosphate-containing compounds are not intentionally added, but may be present in trace amounts due to, for example, impurities or unavoidable environmental contamination. In other words, the amount of material is so small that it does not affect the properties of the composition, which may further include the absence of phosphates in the sealing composition and / or the layer deposited therefrom at levels that would cause environmental burden. The term "substantially free" means that the sealing composition and / or the layer deposited therefrom, if present, contains less than 5 ppm of any or all of the phosphate anions or compounds listed above, based on the total weight of the composition or layer, respectively. The term "essentially free" means that the sealing composition and / or layer comprising the sealing composition contains less than 1 ppm of any or all of the phosphate anions or compounds listed in the preceding paragraph. The term "completely free" means that the sealing composition and / or layer comprising the sealing composition, if present, contains less than 1 ppb of any or all of the phosphate anions or compounds listed in the preceding paragraph.

[0090] The sealing composition may optionally exclude fluoride or a fluoride source. As used herein, "fluoride source" includes monofluoride, difluoride, fluoride complexes, and mixtures thereof known to generate fluoride ions. When a composition and / or a layer or coating containing the same is substantially, essentially, or completely fluoride-free, this includes any form of fluoride ion or fluoride source, but does not include unintended fluoride that may be present in the bath as a result of, for example, a treatment line, municipal water source (e.g., fluoride added to water to prevent dental caries), or fluoride from a pretreated substrate. That is, a substantially, essentially, or completely fluoride-free bath may contain unintended fluoride that may come from these external sources, even if the composition used to make the bath before use on the treatment line is substantially, essentially, or completely fluoride-free.

[0091] For example, the sealing composition can be substantially free of any fluoride source, such as ammonium and alkali metal fluorides, acid fluorides, fluoroboric acid, fluorosilicic acid, fluorotitanic acid, and fluorozirconic acid and their ammonium and alkali metal salts, and other inorganic fluorides, non-exclusive examples of which are zinc fluoride, zinc aluminum fluoride, titanium fluoride, zirconium fluoride, nickel fluoride, ammonium fluoride, sodium fluoride, potassium fluoride, and hydrofluoric acid, and other similar materials known to those skilled in the art.

[0092] Fluoride present in the sealing composition that is not bound to metal ions such as Group IVB metal ions or hydrogen ions, defined herein as "free fluoride," can be measured as an operating parameter in the sealing composition bath using, for example, a fluoride ion-selective electrode ("ISE") available from Thermoscientific, a Symphony® fluoride ion-selective combination electrode supplied by VWR International, or an Orion Dual Star Dual Channel Benchtop Meter equipped with a similar electrode. See, for example, Light and Cappuccino, "Determination of fluoride in toothpaste using an ion-selective electrode," J. Chem. Educ., 52:4, 247-250, April 1975. Fluoride ISEs can be standardized by immersing an electrode in a solution of known fluoride concentration, recording the reading in millivolts, and then plotting these millivolt readings on a logarithmic graph. The millivolt reading of an unknown sample can then be compared to this calibration graph to determine the fluoride concentration. Alternatively, a fluoride ISE can be used with an instrument that performs the calibration calculation internally, allowing a direct reading of the concentration of an unknown sample after calibration.

[0093] Because fluoride ions are small anions with a high charge density, they often form complexes in aqueous solutions with metal ions with a high positive charge density, such as Group IVB metal ions, or with hydrogen ions. Fluoride anions in solution that are ionically or covalently bound to metal cations or hydrogen ions are defined herein as "bound fluoride." Such complexed fluoride ions cannot be measured with a fluoride ISE unless the solution in which they reside is mixed with an ionic strength-adjusting buffer (e.g., citrate anion or EDTA) that releases fluoride ions from such complexes. At that point, all fluoride ions can be measured with a fluoride ISE, and the measurement is known as "total fluoride." Alternatively, total fluoride can be calculated by comparing the weight of fluoride provided in the sealer composition with the total weight of the composition.

[0094] The sealing composition may optionally be substantially free, essentially free, or completely free of cobalt ions or cobalt-containing compounds. As used herein, "cobalt-containing compounds" includes compounds, complexes, or salts containing the element cobalt, such as, for example, cobalt sulfate, cobalt nitrate, cobalt carbonate, and cobalt acetate. When the composition and / or layer or coating comprising it is substantially free, essentially free, or completely free of cobalt, it includes cobalt ions or cobalt-containing compounds in any form.

[0095] The sealing composition may optionally be substantially free, essentially free, or completely free of vanadium ions or vanadium-containing compounds. As used herein, "vanadium-containing compounds" includes compounds, complexes, or salts containing vanadium element, such as vanadates and decavanadates, including, for example, ammonium sodium decavanadate, with alkali metal counterions or ammonium cations. When the composition and / or layer or coating comprising it is substantially free, essentially free, or completely free of vanadium, it contains vanadium ions or vanadium-containing compounds in any form.

[0096] The sealing composition may optionally further contain an indicator compound, so named because it indicates, for example, the presence of a chemical species such as a metal ion, the pH of the composition, etc. As used herein, "indicator," "indicator compound," and like terms refer to a compound that changes color in response to some external stimulus, parameter, or condition, such as the presence of a metal ion, or in response to a particular pH or range of pH.

[0097] The indicator compound used in accordance with the present invention can be any indicator known in the art that indicates the presence of a species, a specific pH, etc. For example, a suitable indicator can be an indicator that changes color after forming a metal ion complex with a specific metal ion. Metal ion indicators are generally highly conjugated organic compounds. As used herein, as understood by those skilled in the art, a "conjugated compound" refers to a compound having two double bonds separated by a single bond, for example, two carbon-carbon double bonds with a single carbon-carbon bond between them. Any conjugated compound can be used in accordance with the present invention.

[0098] Similarly, the indicator compound may be a compound that changes color upon a change in pH; for example, the compound may be one color at an acidic or neutral pH and change color at an alkaline pH, or vice versa. Such indicators are well known and widely available commercially. Thus, an indicator that "changes color upon transition from a first pH to a second pH" (i.e., from a first pH to a second pH that is more or less acidic or alkaline) has a first color (or is colorless) when exposed to the first pH and changes to a second color (or changes from colorless to colored) upon transition to the second pH (i.e., a pH that is more or less acidic or alkaline than the first pH). For example, "An indicator that changes color upon transition to a more alkaline pH (or less acidic pH) changes from a first color / colorless to a second color / colored as the pH transitions from acidic / neutral to alkaline." For example, "An indicator that changes color upon transition to a more acidic pH (or less alkaline pH) changes from a first color / colorless to a second color / colored as the pH transitions from alkaline / neutral to acidic."

[0099] Non-limiting examples of such indicator compounds include methyl orange, xylenol orange, catechol violet, bromophenol blue, green and purple, eriochrome black T, celestine blue, hematoxylin, calmagite, gallocyanin, and combinations thereof. Optionally, the indicator compound may include an organic indicator compound that is a metal ion indicator. Non-limiting examples of indicator compounds include those found in Table 1. Fluorescent indicators that emit light under certain conditions may also be used in accordance with the present invention, although the use of fluorescent indicators may also be specifically excluded. Alternatively, conjugate compounds that exhibit fluorescence are specifically excluded. As used herein, "fluorescent indicator" and similar terms refer to compounds, molecules, pigments, and / or dyes that fluoresce or otherwise exhibit color when exposed to ultraviolet or visible light. "Fluorescing" is understood to mean emitting light after absorbing shorter wavelength light or other electromagnetic radiation. Examples of such indicators, often referred to as "tags," include acridine, anthraquinone, coumarin, diphenylmethane, diphenylnaphthylmethane, quinoline, stilbene, triphenylmethane, anthracine, and / or molecules containing any of these moieties and / or derivatives of any of these, such as rhodamine, phenanthridine, oxazine, fluorone, cyanine, and / or acridine. [Table 1]

[0100] Conjugate compounds useful as indicators can include, for example, catechol violet, as shown in Table 1. Catechol violet (CV) is a sulfonephthalein dye made by condensing two moles of pyrocatechol with one mole of o-sulfobenzoic anhydride. CV has been found to have indicator properties, and when incorporated into compositions with metal ions, it forms complexes, making it useful as a complexometric titration reagent. A blue to blue-purple color is generally observed as compositions containing CV chelate metal ions (i.e., those with a valence of 2 or greater) from the metal substrate.

[0101] Xylenol orange can similarly be used in compositions according to the present invention, as shown in Table 1. Xylenol orange has been found to have metal ion (i.e., those with a valence of 2 or greater) indicator properties, and when incorporated into compositions with metal ions, it forms complexes, making it useful as a complexometric reagent. As compositions containing xylenol orange chelate the metal ions, solutions of xylenol orange turn from red to nearly blue.

[0102] The indicator compound may be present in the sealing composition in an amount of at least 0.01 g / 1000 g sealing composition, for example, at least 0.05 g / 1000 g sealing composition, and in some cases, 3 g or less / 1000 g sealing composition, for example, 0.3 g or less / 1000 g sealing composition. The indicator compound may be present in an amount of 0.01 g / 1000 g sealing composition to 3 g / 1000 g sealing composition, for example, 0.05 g / 1000 g sealing composition to 0.3 g / 1000 g sealing composition.

[0103] Indicator compounds that change color in response to certain external stimuli provide benefits when using sealing compositions, for example, they can serve as a visual indicator that a substrate has been treated with the composition.For example, a sealing composition containing an indicator that changes color when exposed to metal ions present in the substrate will change color when complexed with the metal ions in the substrate, allowing the user to confirm that the substrate has come into contact with the composition.A similar advantage can be achieved by depositing an alkaline or acidic layer on a substrate and contacting the substrate with the composition of the present invention, which changes color when exposed to alkaline or acidic pH.

[0104] Optionally, the sealing composition may further comprise a nitrogen-containing heterocyclic compound. Examples of the nitrogen-containing heterocyclic compound include cyclic compounds having one nitrogen atom, such as pyrrole, and azole compounds having two or more nitrogen atoms, such as pyrazole, imidazole, triazole, tetrazole, and pentazole, azole compounds having one nitrogen atom and one oxygen atom, such as oxazole and isoxazole, or azole compounds having one nitrogen atom and one sulfur atom, such as thiazole and isothiazole. Non-limiting examples of suitable azole compounds include 2,5-dimercapto-1,3,4-thiadiazole (CAS: 1072-71-5), 1H-benzotriazole (CAS: 95-14-7), 1H-1,2,3-triazole (CAS: 288-36-8), 2-amino-5-mercapto-1,3,4-thiadiazole (CAS: 2349-67-9), also known as 5-amino-1,3,4-thiadiazole-2-thiol, and 2-amino-1,3,4-thiadiazole (CAS: 4005-51-0). For example, the azole compound includes 2,5-dimercapto-1,3,4-thiadiazole. Furthermore, the nitrogen-containing heterocyclic compound can be in the form of a salt, such as a sodium salt.

[0105] The nitrogen-containing heterocyclic compound may be present in the sealing composition at a concentration of at least 0.0005 g per liter of composition, for example, at least 0.0008 g per liter of composition, for example, at least 0.002 g per liter of composition, and in some cases may be present in the sealing composition in an amount of 3 g per liter of composition or less, for example, 0.2 g per liter of composition or less, for example, 0.1 g per liter of composition or less. The nitrogen-containing heterocyclic compound may be present in the sealing composition (if present at all) at a concentration of 0.0005 g per liter to 3 g per liter of composition, for example, 0.0008 g per liter to 0.2 g per liter of composition, for example, 0.002 g per liter to 0.1 g per liter of composition.

[0106] The sealing composition can include an aqueous medium and, optionally, can contain other materials, such as at least one organic solvent. Non-limiting examples of suitable such solvents include propylene glycol, ethylene glycol, glycerol, low molecular weight alcohols, and the like. When present at all, the organic solvent can be present in the sealing composition in an amount of at least 1 g of solvent per liter of sealing composition, e.g., at least about 2 g of solvent per liter of sealing solution, and in some cases in an amount of 40 g or less of solvent per liter of sealing composition, e.g., 20 g or less of solvent per liter of sealing solution. When present at all, the organic solvent can be present in the sealing composition in an amount of from 1 g of solvent per liter of sealing composition to 40 g of solvent per liter of sealing composition, e.g., from 2 g of solvent per liter of sealing composition to 20 g of solvent per liter of sealing composition.

[0107] The pH of the sealing composition can be at least 9.5, e.g., at least 10, e.g., at least 11, and in some cases can be 12.5 or less, e.g., 12 or less, e.g., 11.5 or less. The pH of the sealing composition can be 9.5 to 12.5, e.g., 10 to 12, e.g., 11 to 11.5. The pH of the sealing composition can be adjusted, for example, using any acid and / or base as needed. The pH of the sealing composition can be maintained by the inclusion of an acidic material, including carbon dioxide, a water-soluble acid and / or a water-dispersible acid, e.g., nitric acid, sulfuric acid, and / or phosphoric acid. The pH of the sealing composition can be maintained by the inclusion of a basic material, including a carbonate, such as a Group I carbonate or a Group II carbonate, a hydroxide, such as sodium hydroxide, potassium hydroxide, or ammonium hydroxide, ammonia, and / or a water-soluble base and / or a water-dispersible base, including an amine, such as triethylamine or methylethylamine, or a mixture thereof.

[0108] As mentioned above, the sealing composition may include a carrier, often an aqueous medium, such that the composition is in the form of a solution or dispersion of lithium cations in the carrier. The solution or dispersion can be contacted with the substrate by any of a variety of known techniques, such as dipping or immersion, spraying, intermittent spraying, dipping followed by spraying, brushing, or roll coating. When applied to the metal substrate, the solution or dispersion may be at a temperature ranging from 40°F to about 160°F, e.g., from 60°F to 110°F. For example, the process of contacting the metal substrate with the sealing composition can be carried out at ambient or room temperature. The contact time is often from about 1 second to about 15 minutes, e.g., from about 5 seconds to about 2 minutes.

[0109] After contact with the sealing composition, the substrate may optionally be air-dried at room temperature, or may be dried with hot air by briefly exposing the substrate to elevated temperatures, e.g., by using an air knife to flash off water, e.g., in an oven at 15°C to 100°C, e.g., 20°C to 90°C, or by drying the substrate for 10 minutes, e.g., at 70°C, in a heater assembly using infrared heat, or by passing the substrate between squeegee rolls. The substrate surface may be partially, or in some cases completely, dried before later contacting the substrate surface with any water, solution, composition, etc. As used herein with respect to a substrate surface, "fully dried" or "fully dried" means that no moisture is present on the substrate surface visible to the human eye.

[0110] Optionally, after contact with the sealing composition, the substrate is optionally not rinsed or contacted with any aqueous solution (described below) before contacting at least a portion of the substrate surface with a subsequent treatment composition to form a film, layer, and / or coating thereon.

[0111] Optionally, after contact with the sealing composition, the substrate may be optionally contacted with tap water, deionized water, RO water, and / or any aqueous solution known to those skilled in the art of substrate treatment, where such water or aqueous solution may be at a temperature between room temperature (60° F.) and 212° F. The substrate surface may then optionally be dried, e.g., air dried or hot air dried, as described in the previous paragraph, so that the substrate surface may be partially, or in some cases completely, dried before subsequent contact with any water, solution, composition, etc.

[0112] A substrate treated with a conditioner composition of the present invention and a first pretreatment composition may have a reduced number of pits (counted with the naked eye) and / or a reduced percent of substrate surface corrosion on the surface of the substrate after 7 days of exposure to the Neutral Salt Spray Test (ASTM B117) compared to a substrate not treated with a conditioner composition of the present invention and a first pretreatment composition after 7 days of exposure to the Neutral Salt Spray Test (ASTM B117).

[0113] Substrates treated with the conditioner composition of the present invention and the first pretreatment composition may have a reduced number of pits (counting pits containing a depth of greater than 3 μm and a surface area of ​​greater than 10,000 μm^2 (at a depth of 3 μm) as counted using a Keyence VR3200 3D Measuring Macroscope) and / or a reduced percent of substrate surface corrosion on the surface of the substrate after one day of exposure to the Neutral Salt Spray Test (ASTM B117) compared to substrates not treated with the conditioner composition of the present invention and the first pretreatment composition after one day of exposure to the Neutral Salt Spray Test (ASTM B117).

[0114] It has been surprisingly discovered that the combination of a conditioner composition comprising hydroxide anions and a pretreatment composition comprising magnesium cations imparts corrosion protection to treated substrates, and it was a further surprising discovery that coupling such conditioner and pretreatment compositions with known substrate protectant treatments further enhanced performance compared to substrates treated with such known substrate protectant treatments that had not been previously treated with the conditioner and pretreatment compositions of the present invention. It has also been surprisingly discovered that substrates treated with a conditioner composition and a pretreatment composition comprising magnesium cations induce a substrate surface having at least 10 atomic %, e.g., at least 12 atomic %, e.g., at least 13 atomic %, of corrosion protection from the air / substrate surface interface to at least 750 nm below the air / substrate surface interface, as measured by XPS depth profiling (using a Physical Electronics VersaProbe II instrument equipped with a monochromated Al Kα x-ray source (hv=1,486.7 eV) and a concentric hemispherical analyzer).

[0115] According to the present invention, after the substrate has been contacted with the conditioner composition and the first pretreatment composition (and optionally the second pretreatment composition and / or sealing composition), a coating composition comprising a film-forming resin can be deposited on at least a portion of the treated substrate surface. Any suitable technique can be used to deposit such a coating composition on the substrate, including, for example, brushing, dipping, flow coating, spraying, and the like. However, in some cases, as described in more detail below, such deposition of the coating composition can include an electrocoating step in which an electrodepositable composition is deposited on the metal substrate by electrodeposition. In certain other examples, as described in more detail below, such deposition of the coating composition includes a powder coating step. In still other examples, the coating composition can be a liquid coating composition.

[0116] According to the present invention, the coating composition may comprise a thermosetting or thermoplastic film-forming resin. As used herein, the term "film-forming resin" refers to a resin capable of forming a self-supporting, continuous film on at least the horizontal surface of a substrate upon removal of any diluents or carriers present in the composition or upon curing at ambient or elevated temperatures. Conventional film-forming resins that may be used include, but are not limited to, those typically used in automotive OEM coating compositions, automotive refinish coating compositions, industrial coating compositions, architectural coating compositions, coil coating compositions, and aerospace coating compositions, among others. As used herein, the term "thermosetting" refers to a resin that irreversibly "sets" upon curing or crosslinking, in which the polymer chains of the polymeric components are bonded together by covalent bonds. This characteristic is typically associated with crosslinking reactions of the composition components, often induced, for example, by heat or radiation. The curing or crosslinking reaction can also occur under ambient conditions. Upon curing or crosslinking, the thermosetting resin does not melt with the application of heat and is insoluble in solvents. As used herein, the term "thermoplastic" refers to a resin that contains polymeric components that are not bonded by covalent bonds and thereby capable of undergoing liquid flow upon heating and that are soluble in solvents.

[0117] As previously mentioned, in accordance with the present invention, an electrodepositable coating composition comprising a water-dispersible ionic salt group-containing film-forming resin capable of being deposited on a substrate by an electrocoating step is deposited on a metal substrate by electrodeposition.

[0118] Film-forming polymers containing ionic salt groups may include those for use in cationic electrodepositable coating compositions. As used herein, the term "film-forming polymers containing cationic salt groups" refers to polymers containing at least partially neutralized cationic groups, such as sulfonium and ammonium groups, that impart a positive charge. Film-forming polymers containing cationic salt groups may contain active hydrogen functional groups, including, for example, hydroxyl groups, primary or secondary amine groups, and thiol groups. Film-forming polymers containing cationic salt groups that contain active hydrogen functional groups may be referred to as active hydrogen-containing, cationic salt group-containing film-forming polymers. Examples of polymers suitable for use as film-forming polymers containing cationic salt groups include, but are not limited to, alkyd polymers, acrylics, polyepoxides, polyamides, polyurethanes, polyureas, polyethers, and polyesters, among others.

[0119] The film-forming polymer containing cationic salt groups may be present in the cationic electrodepositable coating composition in an amount of 40% to 90% by weight, e.g., 50% to 80% by weight, e.g., 60% to 75% by weight, based on the total weight of resin solids of the electrodepositable coating composition. As used herein, "resin solids" includes the film-forming polymer containing ionic salt groups, the curing agent, and any additional water-dispersible, non-coloring component(s) present in the electrodepositable coating composition.

[0120] Alternatively, the film-forming polymer containing ionic salt groups may include a film-forming polymer containing anionic salt groups for use in anionic electrodepositable coating compositions. As used herein, the term "film-forming polymer containing anionic salt groups" refers to an anionic polymer containing at least partially neutralized anionic functional groups, such as carboxylic acid groups and phosphate groups, that impart a negative charge. The film-forming polymer containing anionic salt groups may contain active hydrogen functional groups. The film-forming polymer containing anionic salt groups that contains active hydrogen functional groups may be referred to as an active hydrogen-containing, anionic salt group-containing film-forming polymer.

[0121] Anionic salt group-containing film-forming polymers can include base-solubilized carboxylic acid group-containing film-forming polymers, such as the reaction product or adduct of a drying oil or semi-drying fatty acid ester with a dicarboxylic acid or anhydride, and the reaction product of a fatty acid ester, an unsaturated acid or anhydride, and any additional unsaturated modifying material, further reacted with a polyol. Also suitable are at least partially neutralized interpolymers of a hydroxy-alkyl ester of an unsaturated carboxylic acid, an unsaturated carboxylic acid, and at least one other ethylenically unsaturated monomer. Yet another suitable anionic electrodepositable resin comprises an alkyd-aminoplast vehicle, i.e., a vehicle containing an alkyd resin and an amine-aldehyde resin. Another suitable anionic electrodepositable resin composition comprises a mixed ester of a resinous polyol. Other acid-functional polymers, such as phosphate-treated polyepoxides or phosphate-treated acrylic polymers, can also be used. Exemplary phosphoric acid-treated polyepoxides are disclosed in U.S. Patent Application Publication No. 2009-0045071, paragraphs

[0004] to

[0015] , and U.S. Patent Application No. 13 / 232,093, paragraphs

[0014] to

[0040] , the cited portions of which are incorporated herein by reference.

[0122] The anionic salt group-containing film-forming polymer may be present in the anionic electrodepositable coating composition in an amount of 50% to 90%, such as 55% to 80%, such as 60% to 75%, based on the total weight of resin solids of the electrodepositable coating composition.

[0123] The electrodepositable coating composition may further comprise a curing agent, which may react with reactive groups, such as active hydrogen groups, of the film-forming polymer containing ionic salt groups to achieve curing of the coating composition to form a coating. Non-limiting examples of suitable curing agents are at least partially blocked polyisocyanates, aminoplast resins, and phenoplast resins, such as phenol-formaldehyde condensates containing their allyl ether derivatives.

[0124] The curing agent can be present in a cationic electrodepositable coating composition in an amount of 10 to 60 weight percent, such as 20 to 50 weight percent, e.g., 25 to 40 weight percent, based on the total weight of resin solids of the electrodepositable coating composition. Alternatively, the curing agent can be present in an anionic electrodepositable coating composition in an amount of 10 to 50 weight percent, such as 20 to 45 weight percent, e.g., 25 to 40 weight percent, based on the total weight of resin solids of the electrodepositable coating composition.

[0125] The electrodepositable coating composition may further include other optional components such as a pigment composition, and various optional additives, such as fillers, plasticizers, antioxidants, biocides, ultraviolet light absorbers and stabilizers, hindered amine light stabilizers, antifoaming agents, fungicides, dispersing aids, flow control agents, surfactants, wetting agents, or combinations thereof.

[0126] The electrodepositable coating composition may contain water and / or one or more organic solvent(s). Water may be present, for example, in an amount of 40% to 90% by weight, e.g., 50% to 75% by weight, based on the total weight of the electrodepositable coating composition. When used, organic solvents may typically be present in an amount of less than 10% by weight, e.g., less than 5% by weight, based on the total weight of the electrodepositable coating composition. The electrodepositable coating composition may, inter alia, be provided in the form of an aqueous dispersion. The total solids content of the electrodepositable coating composition may be 1% to 50% by weight, e.g., 5% to 40% by weight, e.g., 5% to 20% by weight, based on the total weight of the electrodepositable coating composition. As used herein, "total solids content" refers to the nonvolatile content of the electrodepositable coating composition, i.e., materials that do not volatilize when heated to 110°C for 15 minutes.

[0127] Cationic electrodepositable coating compositions can be deposited on conductive substrates by placing the composition in contact with a conductive cathode and a conductive anode, with the surface to be coated being the cathode. Alternatively, anionic electrodepositable coating compositions can be deposited on conductive substrates by placing the composition in contact with a conductive cathode and a conductive anode, with the surface to be coated being the anode. When a sufficient voltage is applied between the electrodes, an adherent film of the electrodepositable coating composition is substantially continuously deposited on the cathode or anode. The applied voltage can be varied, for example, from as low as 1 volt to as high as several thousand volts, e.g., 50 volts to 500 volts. The current density is typically 1.0 to 15 amps per square foot (10.8 to 161.5 amps per square meter) and tends to decrease rapidly during the electrodeposition process, indicating the formation of a continuous, self-insulating film.

[0128] Once the cationic or anionic electrodepositable coating composition has been electrodeposited onto at least a portion of the conductive substrate, the coated substrate can be heated at a temperature and for a time sufficient to cure the electrodeposited coating on the substrate. For cationic electrodeposition, the coated substrate can be heated to a temperature ranging from 250°F to 450°F (121.1°C to 232.2°C), e.g., from 275°F to 400°F (135°C to 204.4°C), e.g., from 300°F to 360°F (149°C to 180°C). For anionic electrodeposition, the coated substrate can be heated to a temperature ranging from 200°F to 450°F (93°C to 232.2°C), e.g., 275°F to 400°F (135°C to 204.4°C), e.g., 300°F to 360°F (149°C to 180°C), e.g., 200°F to 210.2°F (93°C to 99°C). Cure time can depend on the cure temperature as well as other variables, such as the film thickness of the electrodeposited coating and the level and type of catalyst present in the composition. For example, cure times can range from 10 minutes to 60 minutes, e.g., 20 to 40 minutes. The thickness of the resulting cured electrodeposited coating can range from 2 to 50 microns.

[0129] Alternatively, as described above, according to the present invention, after contacting the substrate with the sealing composition, a powder coating composition can then be deposited on at least a portion of the surface of the substrate. As used herein, "powder coating composition" refers to a coating composition that is completely free of water and / or solvents. Therefore, the powder coating composition disclosed herein is not synonymous with the aqueous and / or solvent-based coating compositions known in the art.

[0130] In accordance with the present invention, a powder coating composition can include (a) a film-forming polymer having reactive functional groups, and (b) a curing agent that reacts with the functional groups. Examples of powder coating compositions that can be used in the present invention include the polyester-based ENVIROCRON line of powder coating compositions (commercially available from PPG Industries, Inc.) or epoxy-polyester hybrid powder coating compositions. Alternative examples of powder coating compositions that may be used in the present invention include low-temperature-cure thermosetting powder coating compositions comprising (a) at least one tertiary aminourea compound, at least one tertiary aminourethane compound, or a mixture thereof, and (b) at least one film-forming epoxy-containing resin and / or at least one siloxane-containing resin (e.g., as described in U.S. Pat. No. 7,470,752, assigned to PPG Industries, Inc. and incorporated herein by reference); curable powder coating compositions generally comprising (a) at least one tertiary aminourea compound, at least one tertiary aminourethane compound, or a mixture thereof, and (b) at least one film-forming epoxy-containing resin and / or at least one siloxane-containing resin (e.g., as described in U.S. Pat. No. 7,432,333, assigned to PPG Industries, Inc. and incorporated herein by reference); and curable powder coating compositions generally comprising a solid particle mixture of a reactive group-containing polymer having a Tg of at least 30° C. (e.g., as described in U.S. Pat. No. 7,432,333, assigned to PPG Industries, Inc. and incorporated herein by reference). No. 6,797,387 to Epson Corporation, which is incorporated herein by reference.

[0131] After deposition of the powder coating composition, the coating is often heated to cure the deposited composition. The heating or curing operation is often carried out at a temperature in the range of 150°C to 200°C, for example in the range of 170°C to 190°C, for a period in the range of 10 to 20 minutes. According to the present invention, the resulting film thickness is from 50 microns to 125 microns.

[0132] As mentioned above, according to the present invention, the coating composition can be a liquid coating composition. As used herein, "liquid coating composition" refers to a coating composition that contains water and / or a solvent. Therefore, the liquid coating composition disclosed herein is synonymous with the aqueous and / or solvent-based coating compositions known in the art.

[0133] In accordance with the present invention, a liquid coating composition can include, for example, (a) a film-forming polymer having reactive functional groups and (b) a curing agent that reacts with the functional groups. In other examples, the liquid coating can contain a film-forming polymer that can react with oxygen in the air or coalesce into a film upon evaporation of water and / or solvent. These film-forming mechanisms can require or be accelerated by the application of heat or some type of radiation, such as ultraviolet or infrared light. Examples of liquid coating compositions that can be used in the present invention include the SPECTRACRON® line of solvent-based coating compositions, the AQUACRON® line of water-based coating compositions, and the RAYCRON® line of UV-cured coatings (all commercially available from PPG Industries, Inc.).

[0134] Suitable film-forming polymers that can be used in the liquid coating compositions of the present invention may include (poly)esters, alkyds, (poly)urethanes, isocyanurates, (poly)ureas, (poly)epoxies, anhydrides, acrylics, (poly)ethers, (poly)sulfides, (poly)amines, (poly)amides, (poly)vinyl chlorides, (poly)olefins, (poly)vinylidene fluorides, (poly)siloxanes, or combinations thereof.

[0135] According to the present invention, the substrate contacted with the sealing composition can also be contacted with a primer composition and / or a topcoat composition. The primer coat can be, for example, a chromate-based primer and a high-performance topcoat. According to the present invention, the primer coat can be a conventional chromate-based primer coat, such as one available from PPG Industries, Inc. (product code 44GN072), or a chrome-free primer, such as one available from PPG (DESOPRIME CA7502, DESOPRIME CA7521, DEFT 02GN083, DEFT 02GN084). Alternatively, the primer coat can be a chromate-free primer coat, such as the coating compositions described in U.S. patent application Ser. No. 10 / 758,973, entitled "Corrosion Resistant Coatings Containing Carbon," and U.S. patent application Ser. Nos. 10 / 758,972 and 10 / 758,972, both entitled "Corrosion Resistant Coatings," all of which are incorporated herein by reference, and can be other chrome-free primers known in the art that can meet MIL-PRF-85582 Class N or MIL-PRF-23377 Class N military requirements and can also be used with the present invention.

[0136] As mentioned above, the substrate of the present invention may also include a topcoat. As used herein, the term "topcoat" refers to a mixture of binder(s), which may be an organic or inorganic polymer or polymer blend, typically at least one pigment, and may optionally contain at least one solvent or solvent mixture and may optionally contain at least one curing agent. A topcoat is typically a coating layer in a single-layer or multi-layer coating system whose outer surface is exposed to the atmosphere or environment and whose inner surface is in contact with another coating layer or a polymer substrate. Examples of suitable topcoats include those that comply with MIL-PRF-85285D, such as those available from PPG (Deft 03W127A and Deft 03GY292). According to the present invention, the topcoat may be a high-performance topcoat, such as those available from PPG (Defthane® ELT™ 99GY001 and 99W009). However, as will be understood by those of skill in the art with reference to this disclosure, other topcoats and high performance topcoats may be used in the present invention.

[0137] According to the present invention, the metal substrate may also include a self-priming topcoat or a reinforced self-priming topcoat. The term "self-priming topcoat," also referred to as a "direct-to-substrate" or "direct-to-metal" coating, refers to a mixture of binder(s), which may be an organic or inorganic polymer or polymer blend, typically at least one pigment, optionally containing at least one solvent or solvent mixture, and optionally containing at least one curing agent. The term "reinforced self-priming topcoat," also referred to as a "reinforced direct-to-substrate coating," refers to a mixture of all or part of a functionalized fluorinated binder, such as a fluoroethylene-alkyl vinyl ether, with other binder(s), which may be an organic or inorganic polymer or polymer blend, typically at least one pigment, optionally containing at least one solvent or solvent mixture, and optionally containing at least one curing agent. Examples of self-priming topcoats include those conforming to TT-P-2756A. Examples of self-priming topcoats include those available from PPG (03W169 and 03GY369), and examples of enhanced self-priming topcoats include Defthane® ELT™ / ESPT and product code number 97GY121, both available from PPG. However, other self-priming topcoats and enhanced self-priming topcoats can be used in coating systems according to the present invention, as will be understood by those skilled in the art with reference to this disclosure.

[0138] According to the present invention, the self-priming topcoat and reinforced self-priming topcoat can be applied directly to a sealed substrate. The self-priming topcoat and reinforced self-priming topcoat can optionally be applied to an organic or inorganic polymer coating, such as a primer or paint film. The self-priming topcoat layer and reinforced self-priming topcoat are typically coating layers in a single-layer or multi-layer coating system, where the outer surface of the coating is exposed to the atmosphere or environment and the inner surface of the coating is typically in contact with the substrate or any polymer coating or primer.

[0139] According to the present invention, topcoats, self-priming topcoats, and enhanced self-priming topcoats can be applied to sealed substrates either in a wet state that dries or cures over time, or in a "not fully cured" state, i.e., after solvent evaporation and / or chemical reaction. The coatings can dry or cure either naturally or by accelerated means, such as ultraviolet curing systems or "curing" paints to form films. The coatings can also be applied in a semi-cured or fully cured state, such as an adhesive.

[0140] In addition, colorants and, if necessary, various additives such as surfactants, wetting agents, or catalysts may be included in the coating composition (electrodepositable, powder, or liquid). As used herein, the term "colorant" means any substance that imparts color and / or other opacity and / or other visual effect to the composition. Examples of colorants include pigments, dyes, and tints, such as those used in the paint industry and / or listed by the Dry Color Manufacturers Association (DCMA), as well as special effect compositions.

[0141] Generally, the colorant can be present in the coating composition in any amount sufficient to impart the desired visual and / or color effect. The colorant can comprise 1 to 65 wt. %, for example, 3 to 40 wt. % or 5 to 35 wt. %, based on the total weight of the composition.

[0142] Therefore, in view of the above description, the present invention relates to the following aspects 1 to 22, in particular, but not limited thereto.

[0143] Embodiment 1. A system for treating a metal substrate, comprising: a conditioner composition comprising hydroxide anions; a first pretreatment composition comprising elemental magnesium, an elemental halide, and an oxidizing agent.

[0144] Embodiment 2. The system of embodiment 1, wherein the conditioner composition has a pH of 9.0 to 13.5.

[0145] Embodiment 3. The system of embodiment 1 or embodiment 2, wherein the elemental magnesium and the elemental halide are from a single source.

[0146] Embodiment 4. The system of any of Embodiments 1-3, wherein the elemental magnesium is derived from a first source and the elemental halide is derived from a second source.

[0147] Embodiment 5. The system of any of Embodiments 1-4, wherein the elemental magnesium is present in the first pretreatment composition in an amount from 500 ppm to 6000 ppm, based on the total weight of the first pretreatment composition.

[0148] Embodiment 6. The system of any of Embodiments 1-5, wherein the elemental halide is present in the first pretreatment composition in an amount from 3000 ppm to 40,000 ppm, based on the total weight of the first pretreatment composition.

[0149] Embodiment 7. The system of any of Embodiments 1-6, wherein the oxidizing agent is present in the first pretreatment composition in an amount from 100 ppm to 3000 ppm, based on the total weight of the first pretreatment composition.

[0150] Embodiment 8. The system of any of Embodiments 1-7, wherein the first pretreatment composition has a pH of 1.0 to 7.0.

[0151] Embodiment 9. The system of any of embodiments 1-8, wherein the first pretreatment composition has a pH of 4.0 to 9.0.

[0152] Embodiment 10. The system of any of Embodiments 1-8, wherein the first pretreatment composition has a pH of 7.0 to 11.0.

[0153] Embodiment 11. The system of any one of embodiments 1 to 10, further comprising a cleaning composition.

[0154] Embodiment 12. The system of any one of embodiments 1-11, further comprising an oxygen scavenger.

[0155] Embodiment 13. The system of any one of embodiments 1-12, further comprising a second pretreatment composition comprising a rare earth element.

[0156] Embodiment 14. The system of embodiment 13, wherein the rare earth element is present in the second pretreatment composition in an amount from 50 ppm to 500 ppm, based on the total weight of the second pretreatment composition.

[0157] Embodiment 15. The system of any one of embodiments 1-14, further comprising a sealing composition comprising elemental lithium.

[0158] Embodiment 16. The embodiment of embodiment 15, wherein the lithium element is present in the sealing composition in an amount of 5 ppm to 5500 ppm, based on the total weight of the sealing composition.

[0159] Embodiment 17. A substrate obtainable by the system according to any one of embodiments 1 to 16.

[0160] Aspect 18. The substrate is: (a) a reduction in the number of pits (as counted by the naked eye) on the surface of a substrate after 7 days of exposure to a Neutral Salt Spray Test (ASTM B117) compared to a substrate not treated with the conditioner composition and the first pretreatment composition after 7 days of exposure to the Neutral Salt Spray Test (ASTM B117); (b) a percent reduction in surface corrosion on the surface of the substrate after 7 days of exposure to a Neutral Salt Spray Test (ASTM B117) compared to a substrate not treated with the conditioner composition and the first pretreatment composition after 7 days of exposure to a Neutral Salt Spray Test (ASTM B117); (c) a reduction in the number of pits (counting pits having a depth of greater than 3 μm and a surface area (at a depth of 3 μm) of greater than 10,000 μm^2 counted using a Keyence VR3200 3D Measuring Macroscope) on the surface of the substrate after 1 day of exposure to a Neutral Salt Spray Test (ASTM B117) compared to a substrate not treated with the conditioner composition and the first pretreatment composition after 1 day of exposure to the Neutral Salt Spray Test (ASTM B117); (d) a percent reduction in substrate surface corrosion on the surface of the substrate after one day of exposure to a Neutral Salt Spray Test (ASTM B117) compared to a substrate not treated with the conditioner composition and the first pretreatment composition after one day of exposure to a Neutral Salt Spray Test (ASTM B117); or (e) at least 10 atomic % from the air / substrate surface interface to at least 750 nm below the air / substrate surface interface as measured by XPS depth profiling (using a Physical Electronics VersaProbe II instrument equipped with a monochromated Al kα x-ray source (hv=1,486.7 eV) and a concentric hemispherical analyzer); 18. The substrate of embodiment 17, having at least one of:

[0161] Embodiment 19. A method for treating a substrate, comprising: contacting at least a portion of the substrate with a conditioner composition having a pH greater than 9.0; contacting at least a portion of the substrate contacted with the conditioner composition with a first pretreatment composition comprising elemental magnesium, an elemental halide, and an oxidizing agent.

[0162] Embodiment 20. The method of embodiment 19, further comprising contacting at least a portion of the substrate contacted with the first pretreatment composition with a second pretreatment composition comprising a rare earth element.

[0163] Embodiment 21 The method of embodiment 19 or embodiment 20, further comprising contacting at least a portion of the substrate contacted with the second pretreatment composition with a sealing composition comprising elemental lithium.

[0164] Aspect 22: A substrate obtainable by the method according to any one of aspects 19 to 21.

[0165] Embodiment 23. The substrate is: (a) a reduction in the number of pits (as counted by the naked eye) on the surface of a substrate after 7 days of exposure to a Neutral Salt Spray Test (ASTM B117) compared to a substrate not treated with the conditioner composition and the first pretreatment composition after 7 days of exposure to the Neutral Salt Spray Test (ASTM B117); (b) a percent reduction in surface corrosion on the surface of the substrate after 7 days of exposure to a Neutral Salt Spray Test (ASTM B117) compared to a substrate not treated with the conditioner composition and the first pretreatment composition after 7 days of exposure to a Neutral Salt Spray Test (ASTM B117); (c) a reduction in the number of pits (counting pits having a depth of greater than 3 μm and a surface area (at a depth of 3 μm) of greater than 10,000 μm^2 counted using a Keyence VR3200 3D Measuring Macroscope) on the surface of the substrate after 1 day of exposure to a Neutral Salt Spray Test (ASTM B117) compared to a substrate not treated with the conditioner composition and the first pretreatment composition after 1 day of exposure to the Neutral Salt Spray Test (ASTM B117); (d) a percent reduction in substrate surface corrosion on the surface of the substrate after one day of exposure to a Neutral Salt Spray Test (ASTM B117) compared to a substrate not treated with the conditioner composition and the first pretreatment composition after one day of exposure to a Neutral Salt Spray Test (ASTM B117); or (e) at least 10 atomic % from the air / substrate surface interface to at least 750 nm below the air / substrate surface interface as measured by XPS depth profiling (using a Physical Electronics VersaProbe II instrument equipped with a monochromated Al kα x-ray source (hv=1,486.7 eV) and a concentric hemispherical analyzer); 23. The substrate of embodiment 22, having

[0166] Illustrating the invention are the following examples, which should not be construed as limiting the invention to their details. All parts and percentages in the examples, as well as throughout the specification, are by weight unless otherwise indicated. [Example]

[0167] [Table 2-1] [Table 2-2] *Measure the cerium concentration in the cerium chloride solution as cerium oxide (CeO2) according to the supplier's analysis report. [Table 3] The materials used to prepare the cleaning composition (Example A) are listed in Table 3. Example A was prepared according to the manufacturer's instructions. [Table 4]

[0168] The materials used to prepare the oxygen scavenger composition (Example B) are listed in Table 4. Example B was prepared according to the manufacturer's instructions. [Table 5]

[0169] The materials used to prepare the oxygen scavenger composition (Example C) are listed in Table 5. Example C was prepared by dissolving sodium hydroxide in deionized water under gentle stirring. [Table 6]

[0170] The materials used to prepare Example D, potassium hydroxide composition, are listed in Table 6. Example D was prepared by diluting the potassium hydroxide solution with deionized water with manual stirring. [Table 7]

[0171] The materials used to prepare the magnesium-containing pretreatment compositions (Examples E-H) are listed in Table 7. Each of Examples E-H was prepared by first dissolving a magnesium salt in deionized water. The magnesium compositions were brought to a final pH using the potassium hydroxide composition of Example D. Hydrogen peroxide was then added to the composition and stirred for at least 30 minutes before use. Examples E1, E2, and E3 were prepared as described for Example E, except that the compositions were brought to a final pH by adding hydrogen chloride until the desired pH was reached, as reported in Table 11. [Table 8-1] [Table 8-2]

[0172] The materials used to prepare the rare earth-containing compositions of Examples I and J are listed in Table 8. Example H was prepared by weighing the cerium nitrate, yttrium nitrate, and cerium chloride solutions into individual cups. Approximately 500 g of deionized water was then used to transfer the rare earth solution to a container containing 1000 g of deionized water under gentle agitation. The remainder of the water was added, and the solution was stirred for 10 minutes to ensure homogeneity before adding the hydrogen peroxide. The final composition was stirred for a minimum of 30 minutes before use.

[0173] Example I was prepared by adding the cerium chloride solution to the entire volume of deionized water under gentle agitation. The solution was stirred for 10 minutes to ensure homogeneity before adding the hydrogen peroxide. The final composition was stirred for a minimum of 30 minutes before use. [Table 9]

[0174] The materials used to prepare the sealing composition (Example K) are listed in Table 9. Example K was prepared by dissolving lithium carbonate in deionized water under gentle agitation.

[0175] The pH of each bath prepared is reported in Table 11.

[0176] In the following examples, panels were placed for 7 days of corrosion testing in a neutral salt spray cabinet operated in accordance with ASTM B117. As used herein, references to a salt spray cabinet operated in accordance with ASTM B117 refer to a salt spray cabinet operated in accordance with ASTM B117 that has been modified to verify salt spray pH, tower temperature, and fog volume produced per hour on a weekly (rather than daily) basis.

[0177] Example 1 (Comparative) A 3-inch x 5-inch x 0.032-inch bare aluminum 2024T3 substrate (Priority Metals, Orange County, CA) was hand-wiped with methyl ethyl ketone (100%) and a disposable cloth and allowed to air dry before chemical cleaning. The panel was immersed in the cleaning composition of Example A for 2 minutes at 55°C with gentle agitation. The panel was then immersed in a tap water rinse with gentle agitation at ambient temperature for 1 minute, followed by a 5-second cascade deionized water rinse. The panel was immersed in the oxygen scavenging composition of Example B for 1.5 minutes at ambient temperature, followed by a 1-minute tap water immersion rinse with gentle agitation at ambient temperature, followed by a 5-second cascade deionized water rinse. The panel was then immersed in the pretreatment composition of Example I for 5 minutes at ambient temperature without agitation. After the pretreatment composition, the panel was rinsed with an immersion rinse in deionized water at ambient temperature for 2 minutes with intermittent agitation, followed by a cascade deionized water rinse for 5 seconds. The panel was then immersed in the sealing composition of Example K for 2 minutes at ambient temperature with intermittent agitation. The panel was allowed to air dry overnight under ambient conditions before testing.

[0178] The panels were placed in a neutral salt spray cabinet operated in accordance with ASTM B117 for a 7-day corrosion test. Corrosion performance was evaluated by counting the number of pits (as defined above) visible to the naked eye on the panels. The data are reported in Table 10.

[0179] Example 2 (Comparative) A 3 inch x 5 inch x 0.032 inch bare aluminum 2024T3 substrate (Priority Metals, Orange County, CA) was hand wiped with methyl ethyl ketone (100%) and a disposable cloth and allowed to air dry before chemical cleaning. The panel was immersed in the cleaning composition of Example A at 55°C for 2 minutes with gentle agitation. The panel was then immersed in a tap water rinse with gentle agitation at ambient temperature for 1 minute, followed by a 5-second cascade deionized water rinse. The panel was immersed in the oxygen scavenging composition of Example B for 1.5 minutes at ambient temperature, followed by a 1-minute tap water immersion rinse with gentle agitation at ambient temperature, followed by a 5-second cascade deionized water rinse. The panel was then immersed in the sealing composition of Example K for 2 minutes with intermittent agitation at ambient temperature. The panel was allowed to air dry overnight under ambient conditions before testing.

[0180] The panels were placed in a neutral salt spray cabinet operated in accordance with ASTM B117 for a 7-day corrosion test. Corrosion performance was evaluated by counting the number of pits (as defined above) visible to the naked eye on the panels. The data are reported in Table 10.

[0181] Example 3 (Comparative) A 3-inch x 5-inch x 0.032-inch bare aluminum 2024T3 substrate (Priority Metals, Orange County, CA) was hand-wiped with methyl ethyl ketone (100%) and a disposable cloth and allowed to air dry before chemical cleaning. The panel was immersed in the cleaning composition of Example A for 2 minutes at 55°C with gentle agitation. The panel was then immersed in a tap water rinse with gentle agitation at ambient temperature for 1 minute, followed by a 5-second cascade deionized water rinse. The panel was immersed in the oxygen scavenging composition of Example B for 1.5 minutes at ambient temperature, followed by a 1-minute tap water immersion rinse with gentle agitation at ambient temperature, followed by a 5-second cascade deionized water rinse. The panel was then immersed in the conditioning composition of Example C for 2 minutes, followed by a 1-minute deionized water immersion rinse with intermittent agitation, followed by a 5-second cascade deionized water rinse. The panel was then immersed in the pretreatment composition of Example I for 5 minutes at ambient temperature without agitation. After the pretreatment composition, the panel was rinsed with an immersion rinse in deionized water for 2 minutes at ambient temperature with intermittent agitation, followed by a 5-second cascade deionized water rinse. The panel was then immersed in the sealing composition of Example K for 2 minutes at ambient temperature with intermittent agitation. The panel was allowed to air dry overnight under ambient conditions before testing.

[0182] The panels were placed in a neutral salt spray cabinet operated in accordance with ASTM B117 for a 7-day corrosion test. Corrosion performance was evaluated by counting the number of pits (as defined above) visible to the naked eye on the panels. The data are reported in Table 10.

[0183] Example 4 (Comparative) A 3-inch x 5-inch x 0.032-inch bare aluminum 2024T3 substrate (Priority Metals, Orange County, CA) was hand-wiped with methyl ethyl ketone (100%) and a disposable cloth and allowed to air dry before chemical cleaning. The panel was immersed in the cleaning composition of Example A for 2 minutes at 55°C with gentle agitation. The panel was then immersed in a tap water rinse with gentle agitation at ambient temperature for 1 minute, followed by a 5-second cascade deionized water rinse. The panel was immersed in the oxygen scavenging composition of Example B for 1.5 minutes at ambient temperature, followed by a 1-minute tap water immersion rinse with gentle agitation at ambient temperature, followed by a 5-second cascade deionized water rinse. The panel was then immersed in the pretreatment composition of Example E for 5 minutes, followed by a 2-minute deionized water immersion rinse and a 5-second cascade deionized water rinse. The panel was then immersed in the pretreatment composition of Example I for 5 minutes at ambient temperature without agitation. After the pretreatment composition, the panel was rinsed with an immersion rinse in deionized water for 2 minutes at ambient temperature with intermittent agitation, followed by a 5-second cascade deionized water rinse. The panel was then immersed in the sealing composition of Example K for 2 minutes at ambient temperature with intermittent agitation. The panel was allowed to air dry overnight under ambient conditions before testing.

[0184] The panels were placed in a neutral salt spray cabinet operated in accordance with ASTM B117 for a 7-day corrosion test. Corrosion performance was evaluated by counting the number of pits (as defined above) visible to the naked eye on the panels. The data are reported in Table 10.

[0185] Example 5 (Comparative) A 3-inch x 5-inch x 0.032-inch bare aluminum 2024T3 substrate (Priority Metals, Orange County, CA) was hand-wiped with methyl ethyl ketone (100%) and a disposable cloth and allowed to air dry before chemical cleaning. The panel was immersed in the cleaning composition of Example A for 2 minutes at 55°C with gentle agitation. The panel was then immersed in a tap water rinse with gentle agitation at ambient temperature for 1 minute, followed by a 5-second cascade deionized water rinse. The panel was immersed in the oxygen scavenging composition of Example B for 1.5 minutes at ambient temperature, followed by a 1-minute tap water immersion rinse with gentle agitation at ambient temperature, followed by a 5-second cascade deionized water rinse. The panel was then immersed in the conditioning composition of Example C for 2 minutes, followed by a 1-minute deionized water immersion rinse with intermittent agitation, followed by a 5-second cascade deionized water rinse. The panel was then immersed in the pretreatment composition of Example F for 5 minutes at ambient temperature without agitation. After the pretreatment composition, the panel was placed in an immersion rinse in deionized water and rinsed for 2 minutes at ambient temperature with intermittent agitation, followed by a 5-second cascade deionized water rinse. The panel was then immersed in the pretreatment composition of Example I for 5 minutes at ambient temperature without agitation. After the pretreatment composition, the panel was placed in an immersion rinse in deionized water and rinsed for 2 minutes at ambient temperature with intermittent agitation, followed by a 5-second cascade deionized water rinse. The panel was then immersed in the sealing composition of Example K for 2 minutes at ambient temperature with intermittent agitation. The panel was allowed to air dry overnight under ambient conditions before testing.

[0186] The panels were placed in a neutral salt spray cabinet operated in accordance with ASTM B117 for a 7-day corrosion test. Corrosion performance was evaluated by counting the number of pits (as defined above) visible to the naked eye on the panels. The data are reported in Table 10.

[0187] Example 6 (Comparative) A 3-inch x 5-inch x 0.032-inch bare aluminum 2024T3 substrate (Priority Metals, Orange County, CA) was hand-wiped with methyl ethyl ketone (100%) and a disposable cloth and allowed to air dry before chemical cleaning. The panel was immersed in the cleaning composition of Example A for 2 minutes at 55°C with gentle agitation. The panel was then immersed in a tap water rinse with gentle agitation at ambient temperature for 1 minute, followed by a 5-second cascade deionized water rinse. The panel was immersed in the oxygen scavenging composition of Example B for 1.5 minutes at ambient temperature, followed by a 1-minute tap water immersion rinse with gentle agitation at ambient temperature, followed by a 5-second cascade deionized water rinse. The panel was then immersed in the conditioning composition of Example C for 2 minutes, followed by a 1-minute deionized water immersion rinse with intermittent agitation, followed by a 5-second cascade deionized water rinse. The panel was then immersed in the pretreatment composition of Example G for 5 minutes at ambient temperature without agitation. After the pretreatment composition, the panel was rinsed with an immersion rinse in deionized water at ambient temperature for 2 minutes with intermittent agitation, followed by a cascade deionized water rinse for 5 seconds. The panel was then immersed in the pretreatment composition of Example I for 5 minutes at ambient temperature without agitation. After the pretreatment coating, the panel was rinsed with an immersion rinse in deionized water at ambient temperature for 2 minutes with intermittent agitation, followed by a cascade deionized water rinse for 5 seconds. The panel was then immersed in the sealing composition of Example K for 2 minutes at ambient temperature with intermittent agitation. The panel was allowed to air dry overnight under ambient conditions before testing.

[0188] The panels were placed in a neutral salt spray cabinet operated in accordance with ASTM B117 for a 7-day corrosion test. Corrosion performance was evaluated by counting the number of pits (as defined above) visible to the naked eye on the panels. The data are reported in Table 10.

[0189] Example 7 (Experimental) A 3-inch x 5-inch x 0.032-inch bare aluminum 2024T3 substrate (Priority Metals, Orange County, CA) was hand-wiped with methyl ethyl ketone (100%) and a disposable cloth and allowed to air dry before chemical cleaning. The panel was immersed in the cleaning composition of Example A for 2 minutes at 55°C with gentle agitation. The panel was then immersed in a tap water rinse with gentle agitation at ambient temperature for 1 minute, followed by a 5-second cascade deionized water rinse. The panel was immersed in the oxygen scavenging composition of Example B for 1.5 minutes at ambient temperature, followed by a 1-minute tap water immersion rinse with gentle agitation at ambient temperature, followed by a 5-second cascade deionized water rinse. The panel was then immersed in the conditioning composition of Example C for 2 minutes, followed by a 1-minute deionized water immersion rinse with intermittent agitation, followed by a 5-second cascade deionized water rinse. The panel was then immersed in the pretreatment composition of Example E for 5 minutes at ambient temperature without agitation. After the pretreatment composition, the panel was rinsed with an immersion rinse in deionized water at ambient temperature for 2 minutes with intermittent agitation, followed by a cascade deionized water rinse for 5 seconds. The panel was then immersed in the pretreatment composition of Example I for 5 minutes at ambient temperature without agitation. After the pretreatment composition, the panel was rinsed with an immersion rinse in deionized water at ambient temperature for 2 minutes with intermittent agitation, followed by a cascade deionized water rinse for 5 seconds. The panel was then immersed in the sealing composition of Example K for 2 minutes at ambient temperature with intermittent agitation. The panel was allowed to air dry overnight under ambient conditions before testing.

[0190] The panels were placed in a neutral salt spray cabinet operated in accordance with ASTM B117 for a 7-day corrosion test. Corrosion performance was evaluated by counting the number of pits visible to the naked eye on the panels. The data are reported in Table 10. An image of the panel is shown in Figure 3(E).

[0191] Example 8 (Experimental) A 3-inch x 5-inch x 0.032-inch bare aluminum 2024T3 substrate (Priority Metals, Orange County, CA) was hand-wiped with methyl ethyl ketone (100%) and a disposable cloth and allowed to air dry before chemical cleaning. The panel was immersed in the cleaning composition of Example A for 2 minutes at 55°C with gentle agitation. The panel was then immersed in a tap water rinse with gentle agitation at ambient temperature for 1 minute, followed by a 5-second cascade deionized water rinse. The panel was immersed in the oxygen scavenging composition of Example B for 1.5 minutes at ambient temperature, followed by a 1-minute tap water immersion rinse with gentle agitation at ambient temperature, followed by a 5-second cascade deionized water rinse. The panel was then immersed in the conditioning composition of Example C for 2 minutes, followed by a 1-minute deionized water immersion rinse with intermittent agitation, followed by a 5-second cascade deionized water rinse. The panel was then immersed in the pretreatment composition of Example H for 5 minutes at ambient temperature without agitation. After the pretreatment composition, the panel was rinsed with an immersion rinse in deionized water at ambient temperature for 2 minutes with intermittent agitation, followed by a cascade deionized water rinse for 5 seconds. The panel was then immersed in the pretreatment composition of Example I for 5 minutes at ambient temperature without agitation. After the pretreatment composition, the panel was rinsed with an immersion rinse in deionized water at ambient temperature for 2 minutes with intermittent agitation, followed by a cascade deionized water rinse for 5 seconds. The panel was then immersed in the sealing composition of Example K for 2 minutes at ambient temperature with intermittent agitation. The panel was allowed to air dry overnight under ambient conditions before testing.

[0192] The panels were placed in a neutral salt spray cabinet operated in accordance with ASTM B117 for a 7-day corrosion test. Corrosion performance was evaluated by counting the number of pits visible to the naked eye on the panels. The data are reported in Table 10.

[0193] Example 9 (Experimental) A 3-inch x 5-inch x 0.032-inch bare aluminum 2024T3 substrate (Priority Metals, Orange County, CA) was hand-wiped with methyl ethyl ketone (100%) and a disposable cloth and allowed to air dry before chemical cleaning. The panel was immersed in the cleaning composition of Example A for 2 minutes at 55°C with gentle agitation. The panel was then immersed in a tap water rinse with gentle agitation at ambient temperature for 1 minute, followed by a 5-second cascade deionized water rinse. The panel was immersed in the oxygen scavenging composition of Example B for 1.5 minutes at ambient temperature, followed by a 1-minute tap water immersion rinse with gentle agitation at ambient temperature, followed by a 5-second cascade deionized water rinse. The panel was then immersed in the conditioning solution of Example C for 2 minutes, followed by a 1-minute deionized water immersion rinse with intermittent agitation, followed by a 5-second cascade deionized water rinse. The panel was then immersed in the pretreatment composition of Example E for 5 minutes at ambient temperature without agitation. After the pretreatment composition, the panel was rinsed with an immersion rinse in deionized water for 2 minutes at ambient temperature with intermittent agitation, followed by a 5-second cascade deionized water rinse. The panel was then immersed in the sealing composition of Example K for 2 minutes at ambient temperature with intermittent agitation. The panel was allowed to air dry overnight under ambient conditions before testing.

[0194] The panels were placed in a neutral salt spray cabinet operated in accordance with ASTM B117 for a 7-day corrosion test. Corrosion performance was evaluated by counting the number of pits visible to the naked eye on the panels. The data are reported in Table 10.

[0195] Example 10 (Experimental) A 3-inch x 5-inch x 0.032-inch bare aluminum 2024T3 substrate (Priority Metals, Orange County, CA) was hand-wiped with methyl ethyl ketone (100%) and a disposable cloth and allowed to air dry before chemical cleaning. The panel was immersed in the cleaning composition of Example A for 2 minutes at 55°C with gentle agitation. The panel was then immersed in a tap water rinse with gentle agitation at ambient temperature for 1 minute, followed by a 5-second cascade deionized water rinse. The panel was immersed in the oxygen scavenging composition of Example B for 1.5 minutes at ambient temperature, followed by a 1-minute tap water immersion rinse with gentle agitation at ambient temperature, followed by a 5-second cascade deionized water rinse. The panel was then immersed in the conditioning composition of Example C for 2 minutes, followed by a 1-minute deionized water immersion rinse with intermittent agitation, followed by a 5-second cascade deionized water rinse. The panel was then immersed in the pretreatment composition of Example E for 5 minutes at ambient temperature without agitation. After the pretreatment composition, the panel was placed in a deionized water immersion rinse and rinsed for 2 minutes at ambient temperature with intermittent agitation, followed by a 5-second cascade deionized water rinse. The panel was then immersed in the pretreatment composition of Example J for 5 minutes at ambient temperature without agitation. After the pretreatment composition, the panel was rinsed in a deionized water immersion rinse for 2 minutes at ambient temperature with intermittent agitation, followed by a 5-second cascade deionized water rinse. The panel was then immersed in the sealing composition of Example K for 2 minutes at ambient temperature with intermittent agitation. The panel was allowed to air dry overnight under ambient conditions before testing.

[0196] The panels were placed in a neutral salt spray cabinet operated in accordance with ASTM B117 for a 7-day corrosion test. Corrosion performance was evaluated by counting the number of pits visible to the naked eye on the panels. The data are reported in Table 10.

[0197] The data for Runs 1-10 are reported in Table 10 as the total number of pits across the face of the panel. The pits were counted by visual inspection.

[0198] Examples 11 to 13 (Experimental) Six 3-inch x 5-inch x 0.032-inch bare aluminum 2024T3 substrates (Priority Metals, Orange County, CA) were hand-wiped with methyl ethyl ketone (100%) and a disposable cloth and allowed to air dry before chemical cleaning. The panels were immersed in the cleaning composition of Example A for 2 minutes at 55°C with gentle agitation. The panels were then immersed in a tap water rinse with gentle agitation at ambient temperature for 1 minute, followed by a 5-second cascade deionized water rinse. The panels were immersed in the oxygen scavenging composition of Example B for 1.5 minutes at ambient temperature, followed by a 1-minute tap water immersion rinse with gentle agitation at ambient temperature, followed by a 5-second cascade deionized water rinse. The panels were then immersed in the conditioning composition of Example C for 2 minutes, followed by a 1-minute deionized water immersion rinse with intermittent agitation, followed by a 5-second cascade deionized water rinse. Two panels were then immersed in the pretreatment composition of Example E-1, two panels were immersed in the pretreatment composition of Example E-2, and two panels were immersed in the pretreatment composition of Example E-3, each for 5 minutes at ambient temperature without agitation. After the pretreatment composition, the panels were rinsed in deionized water with an immersion rinse at ambient temperature for 2 minutes with intermittent agitation, followed by a 5-second cascade deionized water rinse. The panels were then immersed in the pretreatment composition of Example I for 5 minutes at ambient temperature without agitation. After the pretreatment composition, the panels were rinsed in deionized water with an immersion rinse at ambient temperature for 2 minutes with intermittent agitation, followed by a 5-second cascade deionized water rinse. The panel was then immersed for 2 minutes at ambient temperature with intermittent agitation in the sealing composition of Example K. The panel was allowed to air dry overnight under ambient conditions before testing.

[0199] The panels were placed in a neutral salt spray cabinet operated in accordance with ASTM B117 for a 7-day corrosion test. Corrosion performance was evaluated by counting the number of pits visible to the naked eye on the panels. Data are reported in Table 10 as the average number of pits on two panels per treatment using pretreatment composition examples E-1, E-2, or E-3. [Table 10] *Number of pits is the average of two panels.

[0200] Panels were analyzed visually. Pits were counted up to 100. If more than 100 pits were present on a panel, the pit count was recorded as >100.

[0201] Comparing the number of pits counted on panels treated according to Comparative Example 1 with the number of pits counted on panels treated according to Examples 7 and 8 after seven days of exposure to neutral salt spray clearly demonstrates the benefit of the hydroxide conditioner, magnesium cations, halide anions, and oxidizer when included in a system having a rare earth-containing pretreatment and a lithium-containing seal. Evidence of improvement is seen by the elimination of pits on the surfaces of the treated panels after exposure to salt spray (Examples 7 and 8 had zero pits), while Comparative Example 1 had 79 corrosion pits. It is clear that the same corrosion benefit is achieved whether the Mg cation and halide anion sources are from a single source or from two different sources.

[0202] A comparison of the number of pits counted on panels treated according to Example 9 after 7 days of exposure to neutral salt spray compared to the number of pits counted on panels treated according to Comparative Example 2 demonstrates the benefit of the hydroxide conditioner, magnesium cations, halide anions, and oxidizer when included in a system with a lithium-containing seal. Evidence of improvement is seen by the measurable reduction in the number of corrosion pits on panels treated according to Example 9 (29 pits) versus panels treated according to Comparative Example 2 (74 pits).

[0203] Comparing the number of pits counted on panels treated according to Example 7 with those treated according to Examples 3-6 demonstrates the effect of the condition composition (including a hydroxide source) and the first pretreatment composition (containing elemental magnesium, a halide, and hydrogen peroxide) on the number of pits on the panels after 7 days of exposure to neutral salt spray in a cabinet operated according to ASTM B117. In contrast, panels treated according to Example 4, which did not include treating the panels with a conditioner composition, had significant pitting (>100 pits) on the substrate surface after 7 days of exposure to neutral salt spray in a cabinet. Furthermore, panels treated according to Example 3, which did not include elemental magnesium or a halide in the first pretreatment composition (i.e., contained only hydrogen peroxide), had 69 pits on the substrate surface after 7 days of exposure to neutral salt spray in a cabinet. Panels treated according to Example 5, which did not include a halide element in the first pretreatment composition, and Example 6, which did not include an oxidizing agent in the first pretreatment composition, each had >100 pits on the substrate surface after 7 days of exposure to neutral salt spray in a cabinet.

[0204] Example 10 shows that yttrium is not required in the second pretreatment composition to reduce the number of pits on the substrate surface. See panels treated according to Examples 1, 7, and 10. [Table 11-1] [Table 11-2]

[0205] Example 14 (Comparative) Two 3-inch by 5-inch by 0.032-inch bare aluminum 2024T3 substrates (Bralco Metals, La Mirada, CA) and four 3-inch by 5-inch by 0.032-inch bare aluminum 2024T3 substrates (Priority Metals, Orange County, CA) were hand-wiped with methyl ethyl ketone (100%) and a disposable cloth and allowed to air dry.* Both panels from Bralco Metals and two panels from Priority Metals were immersed in the cleaning composition of Example A for 2 minutes at 55°C with gentle agitation. The panels were then immersed in a tap water rinse with gentle agitation at ambient temperature for 1 minute, followed by a 5-second cascade deionized water rinse. The panels were immersed in the oxygen scavenging composition of Example B for 1.5 minutes at ambient temperature, followed by a 1-minute tap water immersion rinse with gentle agitation at ambient temperature, followed by a 5-second cascade deionized water rinse. The panels were allowed to air dry overnight under ambient conditions before testing.

[0206] One panel (Bralco) was placed in a neutral salt spray cabinet operated in accordance with ASTM B117 for a 1-day corrosion test, and one panel (Bralco) was placed in a neutral salt spray cabinet operated in accordance with ASTM B117 for a 7-day corrosion test. Images of the panels after the 1-day corrosion test are shown in Figure 1(A), and images of the panels after the 7-day corrosion test are shown in Figure 3(A). Corrosion performance was evaluated by assessing the percentage of the panel corroded or by counting the number of pits visible to the naked eye on the panel. The data are reported in Tables 12 and 13. Corrosion performance was also analyzed using a macroscope as follows. The data are reported in Figure 2.

[0207] The remaining four panels (Priority Metals) were analyzed to determine the elemental concentrations represented at various depths using XPS depth profiling. The data are shown in Figure 4A. XPS depth profiles of the substrates were generated using a Physical Electronics VersaProbe II instrument equipped with a monochromated Al Kα x-ray source (hv = 1,486.7 eV) and a concentric hemispherical analyzer. Charge neutralization was performed using both low-energy electrons (<5 eV) and argon ions. The binding energy axis was calibrated using sputter-cleaned Cu foil (Cu 2p3 / 2 = 932.62 eV, Cu 2p3 / 2 = 75.1 eV) and Au foil (Au 4f7 / 2 = 83.96 eV). Peaks were charge-referenced to the CHx band of the carbon 1s spectrum at 284.8 eV. Measurements were performed at a 45° takeoff angle relative to the sample surface plane. This resulted in a typical sampling depth of 3-6 nm (95% of the signal originated from this depth or shallower). Quantification was performed using the instrument relative sensitivity factor (RSF), which accounts for the X-ray cross section and inelastic mean free path of the electron. Ion sputtering was performed using 2 kV Ar+ raster-scanned over a 2 mm × 2 mm area. The sputtering rate in the Al2O3 layer was 9.5 nm / min. These data, shown in Figure 4A, indicate that the amount of magnesium present at the air / substrate interface was significantly reduced (approximately 10 atomic %) in the panels treated according to Example 14 compared to panels washed with solvent alone (approximately 30 atomic %).

[0208] Example 15 (Experimental) Two 3-inch x 5-inch x 0.032-inch bare aluminum 2024T3 substrates (Bralco Metals, La Mirada, CA) and one bare aluminum 2024T3 substrate (Priority Metals, Orange County, CA) were hand-wiped with methyl ethyl ketone (100%) and a disposable cloth and allowed to air dry before chemical cleaning. The panels were immersed in the cleaning composition of Example A at 55°C for 2 minutes with gentle agitation. The panels were then immersed in a tap water rinse at ambient temperature with gentle agitation for 1 minute, followed by a 5-second cascade deionized water rinse. The panels were immersed in the oxygen scavenging composition of Example B for 1.5 minutes at ambient temperature, followed by a 1-minute tap water immersion rinse at ambient temperature with gentle agitation, followed by a 5-second cascade deionized water rinse. The panel was then immersed in the conditioning composition of Example C for 2 minutes, followed by a 1-minute deionized water immersion rinse with intermittent agitation, followed by a 5-second cascade deionized water rinse. The panel was then immersed in the pretreatment composition of Example E for 5 minutes at ambient temperature without agitation. After the pretreatment composition, the panel was rinsed in deionized water with an immersion rinse at ambient temperature for 2 minutes with intermittent agitation, followed by a 5-second cascade deionized water rinse. The panel was allowed to air dry overnight under ambient conditions before testing.

[0209] One panel (Bralco) was placed in a neutral salt spray cabinet operated in accordance with ASTM B117 for a 1-day corrosion test, and one panel (Bralco) was placed in a neutral salt spray cabinet operated in accordance with ASTM B117 for a 7-day corrosion test. Images of the panels after the 1-day corrosion test are shown in Figure 1(B), and images of the panels after the 7-day corrosion test are shown in Figure 3(B). Corrosion performance was evaluated by assessing the percentage of the panel corroded or by counting the number of pits visible to the naked eye on the panel. The data are reported in Tables 12 and 13. Corrosion performance was also analyzed using a macroscope. The data are reported in Figure 2.

[0210] The remaining panel (Priority Metals) was analyzed to determine the elemental concentrations represented at various depths using XPS depth profiling. The data are shown in Figure 4B. XPS depth profiles of substrates treated according to Example 15 were generated using a Physical Electronics VersaProbe II instrument equipped with a monochromated Al kα x-ray source (hv = 1,486.7 eV) and a concentric hemispherical analyzer. Charge neutralization was performed using both low-energy electrons (<5 eV) and argon ions. The binding energy axis was calibrated using sputter-cleaned Cu foil (Cu 2p3 / 2 = 932.62 eV, Cu 2p3 / 2 = 75.1 eV) and Au foil (Au 4f7 / 2 = 83.96 eV). Peaks were charge-referenced to the CHx band of the carbon 1s spectrum at 284.8 eV. Measurements were performed at a take-off angle of 45° relative to the sample surface plane. This resulted in a typical sampling depth of 3-6 nm (95% of the signal originated at this depth or shallower). Quantification was performed using the instrument relative sensitivity factor (RSF), which accounts for the X-ray cross section and inelastic mean free path of the electron. Ion sputtering was performed using 4 kV Ar+ raster-scanned over a 1.5 mm x 1.5 mm area. The sputtering rate in the Al2O3 layer was 18 nm / min. These data confirmed that magnesium was present in the treated substrate at its highest concentration of approximately 14 atomic % from the air / substrate surface interface to approximately 750 nm below the air / substrate surface interface, then steadily decreased to a concentration of less than 2 atomic % at approximately 2250 nm below the air / substrate surface interface.

[0211] Example 16 Two 3-inch x 5-inch x 0.032-inch bare aluminum 2024T3 substrates (Bralco Metals, La Mirada, CA) were hand-wiped with methyl ethyl ketone (100%) and a disposable cloth and allowed to air dry before chemical cleaning. The panels were immersed in the cleaning composition of Example A for 2 minutes at 55°C with gentle agitation. The panels were then immersed in a tap water rinse with gentle agitation at ambient temperature for 1 minute, followed by a 5-second cascade deionized water rinse. The panels were immersed in the oxygen scavenging composition of Example B for 1.5 minutes at ambient temperature, followed by a 1-minute tap water immersion rinse with gentle agitation at ambient temperature, followed by a 5-second cascade deionized water rinse. The panels were then immersed in the conditioning composition of Example C for 2 minutes, followed by a 1-minute deionized water immersion rinse with intermittent agitation, followed by a 5-second cascade deionized water rinse. The panel was then immersed in the pretreatment composition of Example E for 5 minutes at ambient temperature without agitation. The panel was then immersed in deionized water and rinsed for 2 minutes at ambient temperature with intermittent agitation, followed by a 5-second cascade deionized water rinse. The panel was then immersed in the pretreatment composition of Example I for 5 minutes at ambient temperature without agitation. The panel was then rinsed in deionized water with an immersion rinse for 2 minutes at ambient temperature with intermittent agitation, followed by a 5-second cascade deionized water rinse. The panel was allowed to air dry overnight under ambient conditions before testing.

[0212] One panel was placed in a neutral salt spray cabinet operated in accordance with ASTM B117 for a 1-day corrosion test, and one panel was placed in a neutral salt spray cabinet operated in accordance with ASTM B117 for a 7-day corrosion test. Images of the panel after the 1-day corrosion test are shown in Figure 1(C), and images of the panel after the 7-day corrosion test are shown in Figure 3(C). Corrosion performance was evaluated by assessing the percentage of the panel corroded or by counting the number of pits visible to the naked eye on the panel. The data are reported in Tables 12 and 13. Corrosion performance was also analyzed using a macroscope. The data are reported in Figure 2.

[0213] Example 17 Two 3-inch x 5-inch x 0.032-inch bare aluminum 2024T3 substrates (Bralco Metals, La Mirada, CA) were hand-wiped with methyl ethyl ketone (100%) and a disposable cloth and allowed to air dry before chemical cleaning. The panels were immersed in the cleaning composition of Example A at 55°C for 2 minutes with gentle agitation. The panels were then immersed in a tap water rinse at ambient temperature for 1 minute with gentle agitation, followed by a 5-second cascade deionized water rinse. The panels were immersed in the oxygen scavenging composition of Example B for 1.5 minutes at ambient temperature, followed by a 1-minute tap water immersion rinse at ambient temperature with gentle agitation, followed by a 5-second cascade deionized water rinse. The panels were then immersed in the pretreatment composition of Example I for 5 minutes without agitation at ambient temperature. The panels were then rinsed in deionized water at ambient temperature for 2 minutes with intermittent agitation, followed by a 5-second cascade deionized water rinse. The panels were allowed to air dry overnight under ambient conditions before testing.

[0214] One panel was placed in a neutral salt spray cabinet operated in accordance with ASTM B117 for a 1-day corrosion test, and one panel was placed in a neutral salt spray cabinet operated in accordance with ASTM B117 for a 7-day corrosion test. Images of the panel after the 1-day corrosion test are shown in Figure 1(D), and images of the panel after the 7-day corrosion test are shown in Figure 3(D). Corrosion performance was evaluated by assessing the percentage of the panel corroded or by counting the number of pits visible to the naked eye on the panel. If the surface corrosion of the panel exceeded 15%, the number of pits could not be counted with the naked eye. The data are reported in Tables 12 and 13. Corrosion performance was also analyzed using a macroscope as follows. The data are reported in Figure 2. [Table 12] [Table 13]

[0215] The panels of Examples 14-17 were analyzed visually. If surface corrosion was less than 15%, the pits were counted up to a maximum of 100. If more than 100 pits were present on the panel, the pit count was recorded as >100. If surface corrosion was 15% or greater, the % surface corrosion was recorded. The data in Tables 12 and 13 demonstrate that treating the panels with a hydroxide-containing conditioner composition and a first pretreatment composition (containing magnesium) improves corrosion performance, as demonstrated by the reduction in surface corrosion shown by Example 15.

[0216] The panels of Examples 14-17 were also evaluated using a Keyence VR3200 3D Measuring Macroscope, which uses refractive index measurements to measure 3D surface topology via a non-contact optical method. For each analyzed panel, the surface topology measuring 6.5 cm x 4.4 cm was acquired at a pixel resolution of 14.8 μm and baseline corrected using the software's built-in waveform removal tool at an intensity of 10. Pits were characterized using the software's built-in volume and area analysis tool. This tool was used to count and summarize all pits greater than 3 μm in depth and greater than 10,000 μm^2 in surface area (at a depth of 3 μm). The data are shown in Figure 2.

[0217] As illustrated in Figure 2, the panel treated according to Example 15 had only four pits as determined by macroscopy. The pits averaged about 10 μm deep and about 160 μm in diameter. The dark spots visible in the optical image (Figure 1(B)) were measured to be very superficial at this magnification, with almost none exceeding the 3 μm threshold. The panel treated according to Example 16 had 81 pits, averaging 13 μm deep and 150 μm in diameter. The panels treated according to Examples 14 and 17 had 206 and 292 pits, respectively, averaging about 21 μm deep and about 200 μm in diameter.

[0218] While certain features of the present invention have been described above for purposes of illustration, it will be apparent to those skilled in the art that many variations can be made in the details of the coating compositions, coatings, and methods disclosed herein without departing from the scope of the appended claims. According to a preferred embodiment of the present invention, for example, the following is provided: (Section 1) 1. A system for treating a metal substrate, comprising: a conditioner composition comprising a hydroxide source; a first pretreatment composition comprising elemental magnesium, an elemental halide, and an oxidizing agent. (Section 2) Item 1. The system according to item 1, wherein the conditioner composition has a pH of 9.0 to 13.5. (Section 3) Item 1. The system according to item 1, wherein the magnesium element and the halide element are derived from a single source. (Section 4) Item 1, wherein the magnesium element is derived from a first source and the halide element is derived from a second source. (Section 5) Item 1. The system according to item 1, wherein the magnesium element is present in the first pretreatment composition in an amount of 500 ppm to 6,000 ppm based on the total weight of the first pretreatment composition. (Section 6) Item 10. The system of item 1, wherein the halide element is present in the first pretreatment composition in an amount of 3000 ppm to 40,000 ppm, based on the total weight of the first pretreatment composition. (Section 7) Item 1. The system of item 1, wherein the oxidizing agent is present in the first pretreatment composition in an amount of 100 ppm to 3,000 ppm, based on the total weight of the first pretreatment composition. (Section 8) Item 1. The system according to item 1, wherein the first pretreatment composition has a pH of 1.0 to 7.0. (Section 9) 10. The system of claim 1, further comprising a cleaning composition. (Section 10) 10. The system of claim 1, further comprising an oxygen scavenger. (Section 11) 10. The system of claim 1, further comprising a second pretreatment composition comprising a rare earth element. (Section 12) 12. The system of claim 11, wherein the rare earth element is present in the second pretreatment composition in an amount of 50 ppm to 500 ppm, based on the total weight of the second pretreatment composition. (Section 13) Item 1. The system of item 1, further comprising a sealing composition comprising elemental lithium. (Section 14) Item 14. The system according to item 13, wherein the lithium element is present in the sealing composition in an amount of 5 ppm to 5,500 ppm based on the total weight of the sealing composition. (Section 15) A substrate obtainable by the system described in item 1 above. (Section 16) The substrate is: (a) a reduction in the number of pits (as counted with the naked eye) on the surface of the substrate after 7 days of exposure to a Neutral Salt Spray Test (ASTM B117), compared to a substrate not treated with the conditioner composition and the first pretreatment composition, after 7 days of exposure to the Neutral Salt Spray Test (ASTM B117); (b) a percent reduction in surface corrosion on the surface of the substrate after 7 days of exposure to a Neutral Salt Spray Test (ASTM B117) compared to a substrate not treated with the conditioner composition and the first pretreatment composition after 7 days of exposure to a Neutral Salt Spray Test (ASTM B117); (c) a reduction in the number of pits (counting pits having a depth of greater than 3 μm and a surface area (at a depth of 3 μm) of greater than 10,000 μm^2 counted using a Keyence VR3200 3D Measuring Macroscope) on the surface of the substrate after 1 day of exposure to a Neutral Salt Spray Test (ASTM B117) compared to a substrate not treated with the conditioner composition and the first pretreatment composition after 1 day of exposure to the Neutral Salt Spray Test (ASTM B117); (d) a percent reduction in substrate surface corrosion on the surface of the substrate after one day of exposure to a Neutral Salt Spray Test (ASTM B117) compared to a substrate not treated with the conditioner composition and the first pretreatment composition after one day of exposure to the Neutral Salt Spray Test (ASTM B117); or (e) at least 10 atomic % from the air / substrate surface interface to at least 750 nm below said air / substrate surface interface as measured by XPS depth profiling (using a Physical Electronics VersaProbe II instrument equipped with a monochromated Al kα x-ray source (hv=1,486.7 eV) and a concentric hemispherical analyzer); Item 16. The substrate according to item 15, having at least one of the following: (Section 17) 1. A method of treating a substrate, comprising: contacting at least a portion of the substrate with a conditioner composition having a pH greater than 9.0; contacting at least a portion of the substrate that has been contacted with the conditioner composition with a first pretreatment composition comprising elemental magnesium, an elemental halide, and an oxidizing agent. (Section 18) Item 18. The method of item 17, further comprising contacting at least a portion of the substrate that has been contacted with the first pretreatment composition with a second pretreatment composition comprising a rare earth element. (Section 19) Item 19. The method according to item 18, further comprising contacting at least a portion of the substrate that has been contacted with the second pretreatment composition with a sealing composition containing elemental lithium. (Section 20) A substrate obtainable by the method described in item 17 above. (Section 21) The substrate is: (a) a reduction in the number of pits (as counted with the naked eye) on the surface of the substrate after 7 days of exposure to a Neutral Salt Spray Test (ASTM B117), compared to a substrate not treated with the conditioner composition and the first pretreatment composition, after 7 days of exposure to the Neutral Salt Spray Test (ASTM B117); (b) a percent reduction in surface corrosion on the surface of the substrate after 7 days of exposure to a Neutral Salt Spray Test (ASTM B117) compared to a substrate not treated with the conditioner composition and the first pretreatment composition after 7 days of exposure to a Neutral Salt Spray Test (ASTM B117); (c) a reduction in the number of pits (counting pits having a depth of greater than 3 μm and a surface area (at a depth of 3 μm) of greater than 10,000 μm^2 counted using a Keyence VR3200 3D Measuring Macroscope) on the surface of the substrate after 1 day of exposure to a Neutral Salt Spray Test (ASTM B117) compared to a substrate not treated with the conditioner composition and the first pretreatment composition after 1 day of exposure to the Neutral Salt Spray Test (ASTM B117); (d) a percent reduction in substrate surface corrosion on the surface of the substrate after one day of exposure to a Neutral Salt Spray Test (ASTM B117) compared to a substrate not treated with the conditioner composition and the first pretreatment composition after one day of exposure to the Neutral Salt Spray Test (ASTM B117); or (e) at least 10 atomic % from the air / substrate surface interface to at least 750 nm below said air / substrate surface interface as measured by XPS depth profiling (using a Physical Electronics VersaProbe II instrument equipped with a monochromated Al kα x-ray source (hv=1,486.7 eV) and a concentric hemispherical analyzer); 21. The substrate according to item 20, having at least one of the following:

Claims

1. 1. A system for treating a metal substrate, comprising: a conditioner composition comprising a hydroxide source; a first pretreatment composition comprising elemental magnesium, an elemental halide, and an oxidizing agent; a sealing composition comprising elemental lithium; Including, wherein the conditioner composition has a pH of 9.0 to 13.5; wherein the first pretreatment composition has a pH of 1.0 to 10.0; wherein the elemental magnesium is present in the first pretreatment composition in an amount of 500 ppm to 6,000 ppm (as magnesium cations), based on the total weight of the first pretreatment composition; wherein the elemental halide is present in the first pretreatment composition in an amount of 3000 ppm to 40,000 ppm (as halogen anion), based on the total weight of the first pretreatment composition; wherein the oxidizing agent is present in the first pretreatment composition in an amount of from 100 ppm to 3,000 ppm, based on the total weight of the first pretreatment composition; and wherein the lithium element is present in the sealing composition in an amount of 5 ppm to 5,500 ppm (as lithium cation), based on the total weight of the sealing composition. system.

2. 2. The system of claim 1, wherein said elemental magnesium and said elemental halide are derived from a single source.

3. 2. The system of claim 1, wherein the elemental magnesium is from a first source and the elemental halide is from a second source.

4. 10. The system of claim 1, wherein the first pretreatment composition has a pH of 1.0 to 7.

0.

5. The system of claim 1 further comprising a cleaning composition.

6. 10. The system of claim 1 further comprising an oxygen scavenger.

7. 10. The system of claim 1 further comprising a second pretreatment composition comprising a rare earth element.

8. 8. The system of claim 7, wherein the rare earth element is present in the second pretreatment composition in an amount of 5 ppm to 25,000 ppm (as rare earth cation), based on the total weight of the second pretreatment composition.

9. 10. A method for treating a substrate with the system of claim 1.

10. The treated substrate is: (a) a reduction in the number of pits (as counted by the naked eye) on the surface of the treated substrate after 7 days of exposure to a Neutral Salt Spray Test (ASTM B117), compared to a substrate not treated with the conditioner composition and the first pretreatment composition after 7 days of exposure to a Neutral Salt Spray Test (ASTM B117); (b) a percent reduction in surface corrosion on the surface of the treated substrate after 7 days of exposure to a Neutral Salt Spray Test (ASTM B117), compared to a substrate not treated with the conditioner composition and the first pretreatment composition, after 7 days of exposure to a Neutral Salt Spray Test (ASTM B117); (c) a reduction in the number of pits (counting pits having a depth of greater than 3 μm and a surface area (at a depth of 3 μm) of greater than 10,000 μm^2, counted using a Keyence VR3200 3D Measuring Macroscope) on the surface of the treated substrate after 1 day of exposure to a Neutral Salt Spray Test (ASTM B117) compared to a substrate not treated with the conditioner composition and the first pretreatment composition after 1 day of exposure to the Neutral Salt Spray Test (ASTM B117). (d) a percent reduction in substrate surface corrosion on the surface of the treated substrate after one day of exposure to a Neutral Salt Spray Test (ASTM B117), compared to a substrate not treated with the conditioner composition and the first pretreatment composition after one day of exposure to a Neutral Salt Spray Test (ASTM B117); or (e) a film comprising magnesium, wherein said film comprises at least 10 atomic % magnesium from the air / treated substrate surface interface to at least 750 nm below said air / treated substrate surface interface as measured by XPS depth profiling (using a Physical Electronics VersaProbe II instrument equipped with a monochromated Al kα x-ray source (hv=1,486.7 eV) and a concentric hemispherical analyzer); 10. The method of claim 9, comprising at least one of:

11. 1. A method of treating a substrate, comprising: contacting at least a portion of the substrate with a conditioner composition having a pH greater than 9.0; contacting at least a portion of the substrate that has been contacted with the conditioner composition with a first pretreatment composition comprising elemental magnesium, an elemental halide, and an oxidizing agent; contacting at least a portion of the substrate that has been contacted with the first pretreatment composition with a sealing composition that includes elemental lithium; Including, wherein the conditioner composition has a pH of 9.0 to 13.5; wherein the first pretreatment composition has a pH of 1.0 to 10.0; wherein the elemental magnesium is present in the first pretreatment composition in an amount of 500 ppm to 6,000 ppm (as magnesium cations), based on the total weight of the first pretreatment composition; wherein the elemental halide is present in the first pretreatment composition in an amount of 3000 ppm to 40,000 ppm (as halogen anion), based on the total weight of the first pretreatment composition; wherein the oxidizing agent is present in the first pretreatment composition in an amount of from 100 ppm to 3,000 ppm, based on the total weight of the first pretreatment composition; and wherein the lithium element is present in the sealing composition in an amount of 5 ppm to 5,500 ppm (as lithium cation), based on the total weight of the sealing composition. method.

12. 1. A method of treating a substrate, comprising: contacting at least a portion of the substrate with a conditioner composition having a pH greater than 9.0; contacting at least a portion of the substrate that has been contacted with the conditioner composition with a first pretreatment composition comprising elemental magnesium, an elemental halide, and an oxidizing agent; contacting at least a portion of the substrate that has been contacted with the first pretreatment composition with a second pretreatment composition comprising a rare earth element; contacting at least a portion of the substrate that has been contacted with the second pretreatment composition with a sealing composition that includes elemental lithium; Including, wherein the conditioner composition has a pH of 9.0 to 13.5; wherein the first pretreatment composition has a pH of 1.0 to 10.0; wherein the elemental magnesium is present in the first pretreatment composition in an amount of 500 ppm to 6,000 ppm (as magnesium cations), based on the total weight of the first pretreatment composition; wherein the elemental halide is present in the first pretreatment composition in an amount of 3000 ppm to 40,000 ppm (as halogen anion), based on the total weight of the first pretreatment composition; wherein the oxidizing agent is present in the first pretreatment composition in an amount of from 100 ppm to 3,000 ppm, based on the total weight of the first pretreatment composition; and wherein the lithium element is present in the sealing composition in an amount of 5 ppm to 5,500 ppm (as lithium cation), based on the total weight of the sealing composition. method.

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