Coating compositions comprising aluminum particles

Abstract

The present disclosure is directed to a coating composition comprising a film-forming binder component; and (b) aluminum particles, wherein the weight % of aluminum particle solids on film-forming component solids is at least 50%.

Description

COATING COMPOSITIONS COMPRISING ALUMINUM PARTICLESCROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 659,920 filed lune 14, 2024, which is incorporated herein by reference.FIELD

[0002] The present disclosure is directed to coating compositions comprising (a) a fdm- forming component and (b) aluminum particles, wherein the weight % of aluminum particle solids on film-forming component solids is at least 50%.BACKGROUND

[0003] Coating compositions comprising film-forming binders have been widely applied to, for example, appliances, automobiles, aircraft, and the like. Such coatings may also comprise corrosion inhibitors that provide corrosion resistance, but may contain materials that are potentially toxic, such as chrome. Additionally, such coatings may be exposed to high heat and ultraviolet (UV) light. Coating compositions that provide corrosion resistance and durability, such as resistance to high heat and / or UV are desired, such as those that reduce or eliminate the use of potentially toxic materials.SUMMARY

[0004] The present disclosure is directed to a coating composition comprising, a) a filmforming component and (b) aluminum particles, wherein the weight % of aluminum particle solids on film-forming component solids is at least 50%. Methods for using the compositions to coat at least pail of a substrate and substrates coated according to such methods are also disclosed.DETAILED DESCRIPTION

[0005] The present disclosure is directed to a coating composition comprising a) a filmforming component and (b) aluminum particles, wherein the weight % of aluminum particle solids on film-forming component solids is at least 50%.

[0006] A “film-forming” component is one that, upon hardening and / or curing, can form a continuous film on a surface. A film-forming component may include a resin component and a curing agent component. Film-forming resin, film-former, resin and like terms may all be used interchangeably herein in reference to the resin component. Crosslinker, curing agent, hardener and like terms may all be used interchangeably herein in reference to the curing agentcomponent. The film-forming component may also be referred to herein as the “binder”. The film-forming component may comprise a film-forming resin that can react with itself, that is, undergo a “self-crosslinking” reaction, and / or can react with a crosslinker to form a film. Such reactions may occur at ambient or elevated temperature.

[0007] The resin component of the present disclosure is not limited and may comprise one or more of acrylic polymers, polyesters, polyurethanes, polyamides, polyethers, poly thioethers, polythioesters, polythiols, polyenes, polyols, polysilanes, polysiloxanes, fluoropolymers, polycarbonates, and / or epoxy resins. Generally, these compounds, which need not be polymeric, can be made by any method known to those skilled in the art. The filmforming resin may comprise functional groups, such as at least one of carboxylic acid groups, amine groups, epoxide groups, hydroxyl groups, thiol groups, carbamate groups, amide groups, urea groups, (meth)acrylate groups, styrenic groups, vinyl groups, allyl groups, aldehyde groups, acetoacetate groups, hydrazide groups, cyclic carbonate, and / or maleic acid or anhydride groups. The functional groups on the film-forming resin may be selected so as to be reactive with those on the curing agent, and / or so as to be self-crosslinking.

[0008] The curing agent component according to the present disclosure, when used, may be selected so as to have reactivity with the resin component. The curing agent may comprise a molecule or functional group that may react with the reactive groups, such as active hydrogen groups, on the resin to effectuate cure of the coating composition to form a coating, coating layer, or coating film (which terms may be used interchangeably herein).

[0009] Examples of suitable curing agents include aminoplasts, phenoplasts, polyisocyanates, including blocked isocyanates, polyepoxides, beta-hydroxy alkylamides, polyacids, organometallic acid-functional materials, polyamines, polyamides, polysulfides, polythiols, polyenes such as polyacrylates, polyols, polysilanes and mixtures thereof. Suitable commercially available aminoplast curing agents include those from ALLNEX, such as CYMEL 303, CYMEL 1130, CYMEL 1156 and the like.

[0010] The terms “cure”, “cured”, “harden” and similar terms, which may be used interchangeably herein, refer to the ability of at least a portion of the polymerizable and / or crosslinkable components to undergo a reaction. Curing of the coating composition occurs upon subjecting said composition to curing conditions (e.g., ambient temperature, elevated temperature, actinic radiation, etc.) leading to the reaction of at least a portion of the reactivefunctional groups of the components of the coating composition and resulting in the crosslinking of at least a portion of the components of the composition and formation of an at least partially cured coating layer.

[0011] The coating composition may comprise a resin component comprising a polymer having epoxide functional groups, and the curing agent may comprise a crosslinker comprising amine functional groups or polyamines. The coating composition may comprise one or more epoxy resins comprising epoxide functional groups, such as an aromatic or aliphatic epoxy, such as an aromatic epoxy resin, such as a resin based on Bisphenol A, diglycidyl ethers of Bisphenol A, Bisphenol F, glycerol, novolacs, and the like, or epoxy modified polymers, such as epoxy modified acrylic. Suitable commercially available epoxy resins include EPON 828, EPON 862, EPON 1001, and / or EPON 8111, all available from Westlake Epoxy, and D.E.N. 431, available from Olin. Suitable amino functional group containing curing agents include commercially available materials such as ANCAMINE 2432, ANCAMIDE 2569, ANCAMINE 2672, ANCAMINE 2686, and ANCAMINE K-54, all available from Evonik, and polyether functional amines such as those available under the trade name JEFF AMINE, such as JEFFAMINE D2000, available from Huntsman Corporation. Combinations of these materials may also be used. The amount of film-forming component in the present compositions may range from 40 to 70 wt%, such as 44 to 67 wt%, where wt% is based on total solids weight of the composition. If the filmforming component comprises both a film-forming resin and a curing agent, the weight of these together represents the weight of the film-forming component.

[0012] The coating composition of the present disclosure comprises aluminum (Al) particles. The aluminum particles may comprise any suitable shape such as granular, spherical, cubic, polyhedric, acicular (elongated or fibrous), platy, and / or flake, such as cornflake or silver dollar, and the like. As used herein, “cornflake” refers to flakes having angular edges and uneven surfaces, while “silver dollar” refers to flakes having more rounded edges and smoother, flatter surfaces as compared to the cornflake shaped. The aluminum particles may be used in any form, such as solid particles, an aluminum dispersion, an aluminum paste and the like.

[0013] The aluminum particles may comprise flakes such as leafing aluminum flakes or non-leafing aluminum flakes. As used herein, “leafing aluminum flakes” refers to aluminum particle flakes that tend to align in a generally flat orientation in an applied coating film; they may form a layer where the overlapping flakes are oriented parallel to the surface of a coatingfilm at or near the surface of the film. “At or near the surface of the film” means in the top 30% of the film where the “top” is the surface opposite the surface in contact with the substrate. “Non-leafing aluminum flakes” refers to aluminum particle flakes that tend to orient randomly in an applied coating film and tend to be distributed throughout the film layer (not at or near the surface, like leafing). Non-leafing aluminum flakes may be formed by the addition of strongly polar solvents or wetting agents to leafing aluminum or by using special lubricants, e.g. oleic acid in the milling process. The random orientation of the non-leafing aluminum may be due to the addition of the polar solvents, wetting agents, and / or lubricants, although the inventors do not wish to be bound by this mechanism.

[0014] The coating composition of the present disclosure may be substantially-free of leafing aluminum particles. As used herein, with respect to leafing aluminum, the term “substantially-free” means that any leafing aluminum particles in the composition were introduced through the non-leafing aluminum, such as leafing aluminum that was not adequately treated to become non-leafing, such as less than 10 wt %, or less than 5 wt% leafing aluminum based on total aluminum solid weight. The aluminum particles may consist essentially of nonleafing aluminum particles; that is, the distribution of aluminum particles in the coating layer remains random.

[0015] Different kinds and / or sizes of aluminum particles can be used, including mixtures of aluminum particles. The aluminum particles may comprise any average particle size, such as nano-sized, or micron sized. For example, the aluminum particles may be micron (p) sized powder, or dispersions thereof, such as those having a D(50%) particle size of 5p to 55p, such as at least 5p, such as at least 6p, such as at least 7p, such as at least 8p, such as no more than 55p, such as no more than 20p, such as no more than 10g, such as 5p to 55p, such as 6p to 55p, such as 7p to 55p, such as 8p to 55p, such as 5p to 20p, such as 6p to 20p, such as 7p to 20p, such as 8p to 20p, such as 5p to lOp, such as 6p to lOp, such as 7p to lOp, such as 8p to lOp D(50%). Particle size as reported herein was determined by laser granulometry according to ISO 13320-1. The D(50%) values as reported herein are number based.

[0016] Particle size, as reported herein relating to the aluminum particle, refers to the aluminum particle size at the time of incorporation into the coating composition. Various coating preparation methods may result in the aluminum particles agglomerating, which couldincrease average particle size, or shearing or other action that can reduce the aluminum particle average particle size.

[0017] Suitable aluminum particles include SPARKLE Silver E7000-AR, SPARKLE Silver 5852, commercially available from Silberline Manufacturing Co., Inc., and non-leafing aluminum flakes available from Eckart (Eckart GmbH or Eckart America Corporation).

[0018] It has been a surprising discovery that when the weight % of aluminum particle solids on film-forming component solids is at least 50%, particularly desirable properties may be obtained, as further described below. For example, the coating composition may comprise a weight % of aluminum particle solids on film-forming component solids of at least 50%, such as at least 60%, such as at least 75%, such as at least 90%, such as no more than 125%, such as no more than 100%, such as 50% to 125%, such as 60% to 125%, such as 75% to 125%, such as 90% to 125%, such as 50% to 100%, such as 60% to 100%, such as 75% to 100%, such as 90% to 100%. The weight of the aluminum particles is the total weight of aluminum used in the composition. For example, if solid aluminum particles are used, the weight of the particles is the weight used to determine the weight percent. If a dispersion or paste is used, it is the solid weight of aluminum in the dispersion or paste. The solids weight of the film- forming component is the solids weight of the resin component together with the curing agent component, or just the resin component in the cases of resins that are self-crosslinking. The weight % of aluminum particle solids on film- forming component solids is determined by dividing the weight % aluminum solids in the coating composition by the weight % film-forming component solids in the coating composition.

[0019] The amount of aluminum solids to film-forming component solids can also be expressed as a ratio of % aluminum solids to % film-forming component solids. Ratios within the present disclosure may range from 1.0:2.0 to 1.25:1.00, such as LOTA, 1.0: 1.3, or 1.0: 1.1. The % of aluminum solids and % of film-forming component solids are based on the total solid weight of the coating composition.

[0020] The coating compositions may be thermoset or thermoplastic. Thermoset coating compositions may cure or crosslink under ambient conditions or with exposure to heat or other energy sources. Thermoplastic coating compositions may coalesce and / or dry to form a film upon evaporation of water and / or solvents.

[0021] The coating compositions of the present disclosure may be liquid coating compositions at ambient temperature, such as solvent-based coating compositions (wherein greater than 50% of the total solvent is organic solvent), or water-based coating compositions (wherein 50% or greater of the total solvent is water) or may be powder coating compositions. The present compositions may be either one component (“IK”), or multi-component compositions such as two component (“2K”) or more. A IK composition will be understood as referring to a composition wherein all the coating components are maintained in the same container after manufacture, during storage, etc. A IK composition can be applied to a substrate and cured by any conventional means, such as by heating, forced air, and the like. The present compositions can also be multi-component, which will be understood as compositions in which various components are maintained separately until just prior to application. For example, the present compositions might be packaged as a 2K system, with the resin component in a first package (A) and a curing agent component in a second package (B), whereby all of the other components used in the coating composition are used in any combination in either package (A) or package (B) or in both, or some or all may be in one or more further packages (C). The individual packages are mixed prior to use of the composition.

[0022] The compositions of the present disclosure may further comprise metal oxides, such as zinc oxide, and / or magnesium oxide, such as in a range of 1 wt% to 20 wt% based on total solids weight of the composition. They may be used in an amount of at least 1 wt%, or at least 5 wt%, such as no more than 20 wt%, such as no more than 10 wt%, such as no more than 8 wt%, such as 1 wt% to 8 wt%, such as 1 to 5 wt%, based on total solids weight of the composition. The coating compositions may be substantially free, essentially free, and / or completely free of zinc oxide and / or magnesium oxide. As used herein, with respect to zinc oxide and magnesium oxide, the term “substantially free” means the coating compositions and any resulting coating layer deposited therefrom contain less than 1.0 % by weight, the term “essentially free” means less than 0.05% by weight, and the term “completely free” means less than 0.01% by weight, based on the total solids weight of the coating composition.

[0023] The coating compositions of the present disclosure may additionally include other ingredients commonly used in such compositions. For example, the coating composition may further comprise additional polymers, such as acrylics, polyesters, epoxy, or polyurethanes, and various additives. In addition to materials discussed above, additives that also can be used in thecoating compositions of the present disclosure include water, solvents, such as organic solvents, colorants, fillers including clays, inorganic minerals, abrasion-resistant particles, anti-oxidants, hindered amine light stabilizers, UV light absorbers and stabilizers, surfactants, flow and surface control agents, thixotropic agents, reactive diluents, driers, catalysts, reaction inhibitors, adhesion promoting materials, such as acids and acid derivatives, phosphatized epoxy, silanes, such as epoxy silanes, and other customary additives known to those skilled in the art. As used herein, “colorants” refers to any substance that imparts color and / or other opacity and / or other visual effect to the composition.

[0024] It was surprisingly discovered that aluminum particles used in the amounts recited in the present disclosure may impart corrosion resistance to a coated metallic substrate. The compositions of the present disclosure may further comprise an additional corrosion inhibitor. A “corrosion inhibitor” will be understood as referring to a compound that inhibits corrosion of metals and an “additional” corrosion inhibitor refers to a corrosion inhibitor other than the aluminum particles. Whether an additive functions as a corrosion inhibitor according to the present disclosure may be determined by salt spray corrosion testing according to ASTM Bl 17- 19. Suitable corrosion inhibitors include magnesium and zinc oxides, as well as amino acids, azoles, and lithium-based compounds, such as those described in Int’l Pub. No. WO 2022 / 187844 Al at pars.

[0140] -

[0150] , which paragraphs are incorporated herein by reference. If an additional corrosion inhibitor is used, the wt% of aluminum particles may be greater than the wt% of additional corrosion inhibitor, such as greater than any other inorganic corrosion inhibitor and / or any organic corrosion inhibitor; wt% is based on total solids weight of the composition. The solid weight of aluminum particles in a coating layer deposited from the compositions of the present disclosure may be higher than the solid weight of any corrosion inhibitor that is in an adjacent coating layer. “Higher than” in this context refers to a higher weight % based on total solids weight of the coating composition; due to the amount of aluminum particles in the present coating compositions, “higher than” can be markedly higher, such as 100% higher, 200% higher or even greater. An “adjacent” coating layer is one that is in direct contact with a coating layer deposited from the composition of the present disclosure.

[0025] The coating compositions of the present disclosure may be substantially free, essentially free, and / or completely free of a chromium (VI) -containing material. As used herein, with respect to the chromium (VI) -containing material, the term “substantially free” means thecoating composition and any resulting coating layer contains less than 0.1 % by weight, the term “essentially free” means less than 0.01% by weight, and the term “completely free” means less 0.001% by weight, based on the total solids weight of the coating composition or total weight of the coating.

[0026] Coating compositions of the present disclosure may be prepared using any suitable method. It might be desired to avoid use of high mechanical shear force on the individual flake, such as manual stirring, or air or electric mixing, such as with blade stirrers, or static mixing, magnetic stir bars, and the like, as such aggressive agitation methods, including milling and / or grinding, may not be suitable as it may disrupt alignment of the aluminum particles.

[0027] It has been discovered that coating layers deposited from the present compositions may show improved properties as compared to the same compositions wherein the weight % of aluminum particle solids to film-forming component solids is less than 50%. For example, the present coating layers may have improved heat resistance, UV resistance, and / or impact resistance. The examples below set out the test methods used to evaluate these characteristics.

[0028] Coating compositions prepared in accordance with the present disclosure can be applied to any suitable substrate. Accordingly, the present disclosure is further directed to a method for using the coating compositions of the present disclosure to coat at least a portion of a substrate comprising applying to at least a portion of the substrate any of the coating compositions described herein. Substrates coated at least in part according to this method are also within the present disclosure.

[0029] Suitable substrates include metal substrates, such as flexible and rigid metal substrates, metal alloy substrates, and / or substrates that have been metallized, such as nickel- plated plastic. Additionally, substrates may comprise non-metal substrates, for example, conductive materials including composite materials such as, for example, materials comprising carbon fibers or conductive carbon. The coated substrate may comprise a three-dimensional component formed by an additive manufacturing process, such as a three-dimensional formed composite.

[0030] According to the present disclosure, the metal or metal alloy may comprise, for example, cold rolled steel, hot rolled steel, steel coated with zinc metal, zinc compounds, or zinc alloys, such as electrogalvanized steel, hot-dipped galvanized steel, galvanealed steel,GALV ANNEAL steel, nickel-plated steel, steel plated with zinc alloy, and stainless steel, such as martensitic, duplex, ferritic, austenitic and / or precipitation hardened stainless steel. Steel substrates (such as cold rolled steel or any of the steel substrates listed above) coated with a weldable, zinc-rich or iron phosphide-rich organic coating are also suitable for use in the present disclosure. Such weldable coating compositions are disclosed in U. S. Patent Nos. 4,157,924 and 4,186,036. The substrate may comprise aluminum, aluminum alloys, zinc-aluminum alloys such as GALFAN, GALVALUME, aluminum plated steel, and aluminum alloy plated steel substrates. Non-limiting examples of aluminum alloys include the 1000, 2000, 3000, 4000, 5000, 6000, or 7000 series, particular examples of which are 2024, 2024-T3, 7075, as well as clad aluminum alloys, such as 2024-T3 clad, and cast aluminum alloys, such as, for example, the A356 series. The substrate may comprise a magnesium alloy. Magnesium alloys of the AZ31B, AZ91C, AM60B, or EV31A series also may be used as the substrate. The substrate used in the present disclosure may also comprise other suitable non-ferrous metals such as titanium or copper, as well as alloys of these materials. The substrate may also comprise more than one metal or metal alloy in that the substrate may be a combination of two or more metal substrates assembled together such as hot-dipped galvanized steel assembled with aluminum substrates.

[0031] The coating compositions can be deposited onto or “applied to” substrates by any suitable means known to those skilled in the art. Examples include: coil coating, spraying, such as electrostatic spraying, flow coating, spin coating, curtain coating, brushing, rolling, dipping, or by the use of a fluidized bed.

[0032] Once the coating composition is deposited onto the substrate, it can be dried or cured by any suitable means known to those skilled in the art. Examples of such suitable curing techniques include curing at ambient conditions, elevated temperature, exposure to actinic radiation, and / or combinations thereof. For example, the coating may be cured at ambient temperatures, or at elevated temperatures. “Ambient conditions” generally refer to room temperature (10°C to 32°C) and humidity of 20% relative humidity to 80% relative humidity, while “elevated” temperatures are those at 33 °C or higher; elevated temperatures may be achieved by baking in a thermal oven, induction heating, or infrared heating. The composition may be allowed to fully cure at room temperature, and for any desired time period, such as for 2 weeks. Upon cure a coating layer is formed on the substrate. The coating layer may be formulated as a primer, a basecoat, a topcoat, a sealant, a gap filler, and / or an adhesive.

[0033] Substrates comprising a coating layer deposited from the coating compositions of the present disclosure may contain one or more additional layers over and / or under the layer; these multiple layers are referred to herein as a “multi-layer coating system” or “coating stack”. The coating stack may comprise a pretreatment layer, such as, for example, those described in U.S. Patent Nos. 4,793,867 and 5,588,989, a zirconium containing pretreatment solution such as, for example, those described in U.S. Patent Nos. 7,749,368 and 8,673,091, and / or a solgel, such as those comprising alkoxy-silanes, alkoxy-zirconates, and / or alkoxy-titanates. The coating composition of the present disclosure may be applied over at least a portion of the pretreated layer; one or more additional coating layers may be applied over at least a portion of the present coating layer. Additional coating layers may comprise primers, basecoats, color coats, monocoats, clear coats and / or topcoats. Suitable additional coating layers include any of those known in the art, and each independently may be water-based, solvent-based, in solid particulate form (i.e. , a powder coating composition), or in the form of a powder slurry. The additional coating layers may each be cured independently or applied “wet-on-wet” and cured simultaneously. As used herein, “wet-on-wet” refers to a process wherein a coating, for example a clear coat, is applied over a substantially uncured different coating, for example a color coat, and both coatings are cured simultaneously. Different layers in the coatings stack may contain components that impart a desired property, visual, and / or color effect to the coating, such as corrosion inhibitors; conductive agents such as graphene, conductive carbon black, conductive polymers, or conductive additives; pigments such as those described in U.S. Patent No. 10,844,256 at 8 / 18-43, or other chromatic pigments, and the like.

[0034] The substrate may be new (i.e., newly constructed or fabricated) or it may be refurbished, such as in the case of refinishing or repairing a component of an automobile or aircraft.

[0035] The compositions disclosed herein are not limited and may be suitable for use in various industrial or transportation applications including appliance, coil, automotive applications, commercial transport applications, rail locomotive, marine applications and / or aerospace applications. Suitable substrates for use in the present disclosure include those that are used in the form of sheets or coils, or in the assembly of appliances or of vehicular bodies (such as door, body panel, trunk deck lid, roof panel, hood, roof and / or stringers, rivets, landing gear components, and / or skins used on an aircraft), vehicular frames, vehicular parts, motorcycles,wheels, and industrial structures and components. As used herein, “vehicle” or variations thereof includes all types of aircraft, spacecraft, watercraft, and ground vehicles. A vehicle may be an aerospace vehicle including aircraft such as airplanes including private aircraft, and small, medium, or large commercial passenger, freight, civilian and military aircraft; helicopters, including private, commercial, and military helicopters; or rockets and other spacecraft. A vehicle can include a ground vehicle such as tanks, armored cars, trailers, cars, trucks, buses, vans, construction vehicles, golf carts, motorcycles, bicycles, trains, and railroad cars. A vehicle can also include watercraft such as, for example, ships, boats, and hovercraft. The coating composition may be utilized to coat surfaces and parts thereof. A part may include multiple surfaces. A part may include a portion of a larger pail, assembly, or apparatus. A portion of a pail may be coated with the coating composition of the present disclosure, or the entire part may be coated. An “aircraft part” refers to any part used on any aircraft, internally or externally, made of any substrate, and may include engine accessory and propulsion parts where heat resistance and UV resistance are particularly desired.

[0036] Coating compositions of the present disclosure may be used for coating commercial goods manufacture and / or refinish.

[0037] Coating compositions of the present disclosure may be used for coatings that provide UV resistance, heat resistance, and / or impact resistance.

[0038] Any numerical range recited herein is intended to include all sub-ranges subsumed therein. Singular encompasses plural and vice versa. For example, although reference is made herein to “a” film-forming component, “a” film-forming resin, “a” curing agent, “an” aluminum particle, and the like, one or more of each of these and any other components can be used. Also, as used herein, the term “polymer” refers to prepolymers, oligomers and both homopolymers and copolymers; the prefix “poly” refers to two or more. Amine includes polyamine. When ranges are given, any endpoints of those ranges and / or numbers within those ranges can be combined with the scope of the present disclosure. “Including”, “such as”, “for example” and like terms means “including / such as / for example but not limited to”. The term “(meth)acrylic” means methacrylic and / or acrylic, and the terms “acrylic” and “acrylate” are used interchangeably (unless to do so would alter the intended meaning) and include acrylic acids, anhydrides, and derivatives thereof, lower alkyl-substituted acrylic acids, e.g., C1-C2 substituted acrylic acids, such as methacrylic acid, methacrylic acid, etc., and their C1-C6 alkylesters and hydroxyalkyl esters, unless clearly indicated otherwise. As used herein, the transitional term “comprising” (and other comparable terms, c.g., “containing” and “including”) is “open-ended” and open to the inclusion of unspecified matter. Although described in terms of “comprising”, the terms “consisting essentially of’ and “consisting of’ are also within the scope of the disclosure. As used herein, the terms “on,” “onto,” “applied on,” “applied onto,” “formed on,” “deposited on,” “deposited onto,” “injected on,” “injected onto” and the like mean formed, overlaid, deposited, or provided on, but not necessarily in contact with, a substrate surface. For example, a composition “applied onto” a substrate surface does not preclude the presence of one or more other intervening coating layers or films of the same or different composition located between the composition and the substrate surface.

[0039] Aspects of the disclosure include:

[0040] Aspect 1. A film-forming coating composition comprising:(a) a film-forming component; and(b) aluminum particles, wherein the weight % of aluminum particle solids to the film-forming component solids is at least 50%.

[0041] Aspect 2. The composition of aspect 1, wherein the film-forming component comprises:(a) a resin component; and(b) a curing agent component.

[0042] Aspect 3. The composition of aspect 2, wherein the (a) resin component comprises epoxide functional groups and the (b) curing agent component comprises amine functional groups.

[0043] Aspect 4. The composition of any preceding aspect, wherein the filmforming component comprises aromatic epoxy.

[0044] Aspect 5. The composition of any preceding aspect, wherein the filmforming component comprises a diglycidyl ether of Bisphenol A and / or Bisphenol F.

[0045] Aspect 6. The composition of any preceding aspect, wherein the filmforming component comprises polyamine.

[0046] Aspect 7. The composition of any preceding aspect, wherein the filmforming component comprises polyetheramine.

[0047] Aspect 8. The composition of any preceding aspect, wherein the weight % of aluminum particle solids on film-forming component solids is 50% or greater.

[0048] Aspect 9. The composition of any preceding aspect, wherein the weight % of aluminum particle solids on film-forming component solids is 60% or greater.

[0049] Aspect 10. The composition of any preceding aspect, wherein the weight % of aluminum particle solids on film-forming component solids is 75% or greater.

[0050] Aspect 11. The composition of any preceding aspect, wherein the weight % of aluminum particle solids on film-forming component solids is 90% or greater.

[0051] Aspect 12. The composition of any preceding aspect, wherein the weight % of aluminum particle solids on film-forming component solids is no more than 125%.

[0052] Aspect 13. The composition of any preceding aspect, wherein the weight % of aluminum particle solids on film-forming component solids is no more than 100%.

[0053] Aspect 14. The composition of any preceding aspect, wherein the weight % of aluminum particle solids on film-forming component solids is 50% to 125%.

[0054] Aspect 15. The composition of any preceding aspect, wherein the weight % of aluminum particle solids on film-forming component solids is 60% to 125%.

[0055] Aspect 16. The composition of any preceding aspect, wherein the weight % of aluminum particle solids on film-forming component solids is 75% to 125%.

[0056] Aspect 17. The composition of any preceding aspect, wherein the weight % of aluminum particle solids on film-forming component solids is 90% to 125%.

[0057] Aspect 18. The composition of any preceding aspect, wherein the weight % of aluminum particle solids on film-forming component solids is 50% to 100%.

[0058] Aspect 19. The composition of any preceding aspect, wherein the weight % of aluminum particle solids on film-forming component solids is 60% to 100%.

[0059] Aspect 20. The composition of any preceding aspect, wherein the weight % of aluminum particle solids on film-forming component solids is 75% to 100%.

[0060] Aspect 21. The composition of any preceding aspect, wherein the weight % of aluminum particle solids on film-forming component solids is 90% to 100%.

[0061] Aspect 22. The composition of any preceding aspect, wherein the ratio of % aluminum solids to % film-forming component solids based on the total solid weight of the composition is 1.0:2.0.

[0062] Aspect 23. The composition of any preceding aspect, wherein the ratio of % aluminum solids to % film-forming component solids, based on the total solid weight of the composition is 1.0:1.5.

[0063] Aspect 24. The composition of any preceding aspect, wherein the ratio of % aluminum solids to % film-forming component solids, based on the total solid weight of the composition is 1.0:1.3.

[0064] Aspect 25. The composition of any preceding aspect, wherein the ratio of % aluminum solids to % film-forming component solids, based on the total solid weight of the composition is 1.0: 1.1.

[0065] Aspect 26. The composition of any preceding aspect, wherein the ratio of % aluminum solids to % film-forming component solids, based on the total solid weight of the composition is 1.25:1.00.

[0066] Aspect 27. The composition of any preceding aspect, wherein the aluminum particles comprise a D(50%) particle size of at least 5p.

[0067] Aspect 28. The composition of any preceding aspect, wherein the aluminum particles comprise a D(50%) particle size of at least 6p.

[0068] Aspect 29. The composition of any preceding aspect, wherein the aluminum particles comprise a D(50%) particle size of at least 7p.

[0069] Aspect 30. The composition of any preceding aspect, wherein the aluminum particles comprise a D(50%) particle size of at least 8p.

[0070] Aspect 31. The composition of any preceding aspect, wherein the aluminum particles comprise a D(50%) particle size of no more than 55p.

[0071] Aspect 32. The composition of any preceding aspect, wherein the aluminum particles comprise a D(50%) particle size of no more than 20p.

[0072] Aspect 33. The composition of any preceding aspect, wherein the aluminum particles comprise a D(50%) particle size of no more than lOp.

[0073] Aspect 34. The composition of any preceding aspect, wherein the aluminum particles comprise a D(50%) particle size of 5p to 55p.

[0074] Aspect 35. The composition of any preceding aspect, wherein the aluminum particles comprise a D(50%) particle size of 5 . to 20p.

[0075] Aspect 36. The composition of any preceding aspect, wherein the aluminum particles comprise a D(50%) particle size of 5 . to 10p.

[0076] Aspect 37. The composition of any preceding aspect, wherein the aluminum particles are in a dispersion.

[0077] Aspect 38. The composition of any preceding aspect, wherein the aluminum particles are in a paste.

[0078] Aspect 39. The composition of any preceding aspect, wherein the aluminum particles comprise spherical particles.

[0079] Aspect 40. The composition of any preceding aspect, wherein the aluminum particles comprise flakes.

[0080] Aspect 41. The composition of any preceding aspect, wherein the aluminum particles comprise cornflakes.

[0081] Aspect 42. The composition of any preceding aspect, wherein the aluminum particles comprise silver dollar flakes.

[0082] Aspect 43. The composition of any preceding aspect, wherein the aluminum particles comprise leafing aluminum flakes.

[0083] Aspect 44. The composition of any preceding aspect, wherein the aluminum particles comprise non-leafing aluminum flakes.

[0084] Aspect 45. The composition of any preceding aspect except aspect 43, wherein the aluminum particles are substantially-free of leafing aluminum flakes.

[0085] Aspect 46. The composition of any preceding aspect except aspect 43, wherein the aluminum particles consist essentially of non-leafing aluminum particles.

[0086] Aspect 47. The composition of any preceding aspect, wherein the composition further comprises an additional corrosion inhibitor.

[0087] Aspect 48. The composition of any preceding aspect, wherein the composition further comprising a metal oxide.

[0088] Aspect 49. The composition of any preceding aspect, further comprising zinc oxide.

[0089] Aspect 50. The composition of any preceding aspect, further comprising magnesium oxide.

[0090] Aspect 51. The composition of any of aspects 48 to 50, wherein the amount of metal oxide is 1% to 20% by weight, based on the total solids weight of the composition.

[0091] Aspect 52. The composition of any of aspects 48 to 51, wherein the amount of metal oxide is 1% to 8% by weight, based on the total solids weight of the composition.

[0092] Aspect 53. The composition of any of aspects 48 to 52, wherein the amount of metal oxide is 1 % to 5% by weight, based on the total solids weight of the composition.

[0093] Aspect 54. The composition of any of aspects 47 to 53, wherein the wt% of aluminum particles is greater than the wt% of additional corrosion inhibitor, where wt% is based on total solids weight of the composition.

[0094] Aspect 55. The composition of any preceding aspect, wherein the composition is a liquid coating composition.

[0095] Aspect 56. The composition of any preceding aspect, wherein the composition is solvent-based.

[0096] Aspect 57. The composition of any preceding aspect except aspect 56, wherein the composition is water-based.

[0097] Aspect 58. The composition of any preceding aspect, wherein the composition is a powder coating composition.

[0098] Aspect 59. The composition of any preceding aspect, wherein the composition is a one component coating composition.

[0099] Aspect 60. The composition of any preceding aspect except aspect 59, wherein the composition is a multi-component coating composition, wherein the film-forming component comprises a film- forming resin and a curing agent, wherein the resin is in one component and the curing agent is in another component.

[0100] Aspect 61. The composition of any preceding aspect, wherein the coating composition is substantially free, essentially free, and / or completely free of a chromium (VI)- containing material.

[0101] Aspect 62. The composition of any preceding aspect, wherein a coating layer deposited from said composition, when cured to a dry film thickness of lOp to 25p, has a Delta E heat resistance of 5 or less as measured using the Heat Resistance Test.

[0102] Aspect 63. The composition of any preceding aspect, wherein a coating layer deposited from said composition, when cured to a dry film thickness of lOp to 25 p, has a Delta E heat resistance of 4 or less as measured using the Heat Resistance Test.

[0103] Aspect 64. The composition of any preceding aspect, wherein a coating layer deposited from said composition, when cured to a dry film thickness of lOp to 25 p, has a Delta E UV resistance of less than 4 as measured according to the UV Resistance Test.

[0104] Aspect 65. The composition of any preceding aspect, wherein a coating layer deposited from said composition, when cured to a dry film thickness of lOp to 25 p, has a Delta E UV resistance of 3 or less as measured according to the UV Resistance Test.

[0105] Aspect 66. The composition of any preceding aspect, wherein a coating layer deposited from said composition, when cured to a dry film thickness of lOp to 25p, has a forward impact resistance of at least 50 in-lbs as measured according to the Impact Resistance Test.

[0106] Aspect 67. A method for using the composition of any preceding aspect to coat at least a portion of a substrate comprising applying the coating composition to at least a portion of the substrate.

[0107] Aspect 68. A substrate coated according to the method of aspect 67.

[0108] Aspect 69. The coated substrate of aspect 68, wherein the substrate comprises a metal or metal alloy.

[0109] Aspect 70. The coated substrate of any of aspects 68 to 69, wherein the substrate comprises steel.

[0110] Aspect 71. The coated substrate of any of aspects 68 to 70, wherein the substrate comprises aluminum.

[0111] Aspect 72. The coated substrate of any of aspects 68 to 71, wherein the substrate comprises an aluminum alloy.

[0112] Aspect 73. The coated substrate of any of aspects 68 to 72, wherein the substrate comprises a 2000 series aluminum alloy.

[0113] Aspect 74. The coated substrate of any of aspects 68 to 73, wherein the substrate comprises a 7000 series aluminum alloy.

[0114] Aspect 75. The coated substrate of any of aspects 68 to 74, wherein the substrate comprises a 2024 aluminum alloy.

[0115] Aspect 76. The coated substrate of any of aspects 68 to 75, wherein the substrate comprises a 2024-T3 aluminum alloy.

[0116] Aspect 77. The coated substrate of any of aspects 68 to 76, wherein the substrate comprises a 7075 aluminum alloy.

[0117] Aspect 78. The coated substrate of any of aspects 68 to 77, wherein the substrate comprises a 6000 series aluminum alloy.

[0118] Aspect 79. The coated substrate of any of aspects 68 to 78, wherein the substrate comprises a 6061 aluminum alloy.

[0119] Aspect 80. The coated substrate of any of aspects 68 to 79, wherein the substrate comprises a metal or metal alloy in the form of a metal sheet.

[0120] Aspect 81. The coated substrate of any of aspects 68 to 80, wherein the substrate comprises a metal or metal alloy in the form of a coil.

[0121] Aspect 82. The coated substrate of any of aspects 68 to 81, wherein the substrate comprises a metal or metal alloy in the form of a three-dimensional shaped part.

[0122] Aspect 83. The coated substrate of any of aspects 68 to 82, wherein the substrate comprises a metal or metal alloy in the form of a composite material.

[0123] Aspect 84. The coated substrate of any of aspects 68 to 83, wherein the coating layer forms part of a coating stack.

[0124] Aspect 85. The coated substrate of aspect 84, wherein the coating layer is adjacent to another coating layer in the coating stack and the solid weight of aluminum particles in the coating layer is higher than the solid weight of any corrosion inhibitor in the adjacent coating layer.

[0125] Aspect 86. The coated substrate of any of aspects 68 to 85, wherein the substrate comprises a vehicle part.

[0126] Aspect 87. The coated substrate of any of aspects 68 to 86, wherein the substrate comprises an aircraft part.

[0127] Aspect 88. The coated substrate of any of aspects 68 to 87, wherein the substrate comprises a three-dimensional component formed by an additive manufacturing process.

[0128] Aspect 89. The coating composition of any of aspects 1 to 66, wherein the composition is substantially free, essentially free, and / or completely free of zinc oxide.

[0129] Aspect 90. The coating composition of any of aspects 1 to 66, wherein the composition is substantially free, essentially free, and / or completely free of magnesium oxide.

[0130] Aspect 91. The coating composition of any of aspects 1 to 66, wherein the composition comprises 40-70 wt% film-forming component, where wt% is based on total solid weight of the composition.

[0131] Aspect 92. The coating composition of aspect 91, wherein the composition comprises 44-67 wt% film-forming component, where wt% is based on total solid weight of the composition.EXAMPLES

[0132] The following examples are intended to illustrate the disclosure and should not be construed as limiting the disclosure in any way.Coating Preparations: CONTROLS 1-2 and EXAMPLES 1-4

[0133] Two component (2K), epoxy-amine coating compositions, CONTROLS 1 - 2 (with less than 50% weight % of aluminum solids to film-forming component solids), and EXAMPLES 1 - 4 (with 50% or greater weight % aluminum solids on film-forming component solids), were prepared using the materials and weights shown in Table 2.

[0134] For each BASE, an aluminum slurry was prepared by dispersing the SPARKLE Silver E7000-AR (D(50%) 7p Non-Leafing Aluminum Particles, 64% solids by weight, from Silberline) into the solvents under gentle agitation using an air mixer to form a homogenous mixture. The slurry was kept at room temperature for 16-24 hours, then combined with the epoxy resins under mild agitation using an air mixer.

[0135] Before application of the coating compositions, each BASE was stirred for 5 minutes using an air mixer with a propeller blade. ACTIVATOR was added to each BASE under mild agitation using an air mixer to make CONTROLS 1-2 and EXAMPLES 1-4. The compositions were stirred until each was homogenous.Table 2: Coating Compositions - CONTROLS 1 - 2 and EXAMPLES 1 - 4Substrates And Coating Applications:

[0136] Coating compositions were applied on 2024 T3 Clad aluminum panels (dimensions 3 x 6 x 0.02 inches) from Bralco Metals.

[0137] Coatings for NSS corrosion testing were applied on abraded bare 2024-T3 grade aluminum panels from Bralco Metals.

[0138] All panels were machine-scrubbed with an abrasive pad, SCOTCHBRITE 7447 PRO, wiped with methyl ethyl ketone (MEK) solvent, and dried under ambient conditions prior to coating application.

[0139] CONTROL and EXAMPLE coating compositions were applied using HVLP spray equipment (Vendor: Anest Iwata, Model: LPH300LV) with a tip size of 1.2 mm and a pressure setting of 30 psi, within 60 minutes of combining base and activator. CONTROL and EXAMPLE coatings were applied to a dry film build of 0.5 - 0.8 mils (12.5 - 20p).

[0140] The applied coatings were cured at ambient conditions for 14 days prior to testing coated substrates.Coating Test Methods:

[0141] Coated substrates were evaluated using the following test methods:

[0142] Heat Resistance Test: Heat resistance was tested by exposing coated cured panels to 400°F (204.4°C) for 72 hours. The Delta E color change was measured using a closetolerance benchtop spectrophotometers Datacolor® Spectro 1000.

[0143] UY Resistance Test: UV resistance was determined by exposing coated cured panels to UV-B for 3000 hours according to ASTM G-154. The Delta E color change was measured using a close-tolerance benchtop spectrophotometer Datacolor® Spectro 1000.

[0144] Impact Resistance Test: Forward impact resistance was determined according to ASTM D2794-19. The forward impact test was done by subjecting the coated side of the panel to an impact of 50 inch-pounds (in-lbs) using a Gardener 160 inch-pounds capacity impact testing machine.

[0145] Neutral Salt Spray Corrosion (NSS) Resistance Test: Corrosion resistance was determined by exposing coated cured panels for 3000 hours according to ASTM Bl 17-19. Three test panels were prepared as described above for each coating composition using three abraded bare aluminum panels of approximate 0.032inch thickness. Two diagonal marks (scribe lines) were machine scribed extending from corner to corner on each panel. The width of scribe lines was between 0.031 and 0.064 inch and penetrated through the coating and into the base metal. Test panels were exposed to 5 percent salt spray fog for 3000 hours, with painted side up. The panels were visually examined for corrosion and blisters after salt spray exposure.

[0146] Crosshatch Adhesion Test: Crosshatch adhesion was determined according to ASTM D3359-17 (Standard Test Methods for Measuring Adhesion by Tape Test), method B. Dry adhesion was tested after fully curing the coating system for 14 days. Wet adhesion was tested after immersing fully cured coated panels into de-ionized water for 7 days at ambient temperature. Wet adhesion was then tested within 20 minutes after the panels were pulled out from the water and wiped dry.

[0147] Pencil Hardness Test: Pencil hairiness was determined in accordance with ASTM D3363-22 (Standard Test Method for Film Hardness by Pencil Test).

[0148] Fluids Resistance Test: Fluids resistance was tested by immersing fully cured coated panels in the test fluid, hydraulic fluid SKYDROL LD4, for 20 days at ambient temperature. Fluid resistance was then tested after the panels were pulled out from the test fluid. Excess fluid was removed by gauze and the panels were rinsed with water and dried at ambient conditions for an hour before the Pencil Hardness Test was performed.Coating Test Performance:

[0149] Coating testing results are shown in Tables 3 and 4.Table 3: Corrosion Resistance for Coating Layers of Compositions Comprising Film-forming Binder and Aluminum Particles using the coating of EXAMPLE 2,

[0150] As shown in Table 3, coating layers formed from the composition according to the present disclosure passed 3000 hours NSS corrosion resistance testing.Table 4: Testing Results for CONTROLS 1 - 2 AND EXAMPLES 1 - 4

[0151] As shown in Tabic 4, coating layers formed from EXAMPLES 1 to 4 according to the present disclosure had significantly improved resistance to both heat and UV-B exposure as demonstrated by low color change (Delta E), as well as improved impact resistance, as compared with CONTROLS 1 - 2, while maintaining adhesion, hardness, and fluid resistance. EXAMPLES 1-4 had 400°F (204°C) heat exposure Delta E less than 5, 3000-hour UV-B exposure Delta E less than 3 and passed 50 in-lbs forward impact.

[0152] Whereas particular features of the present disclosure have been described above for purposes of illustration, it will be evident to those skilled in the art that numerous variations of the details of the coating composition, coating, and methods disclosed herein may be made without departing from the scope in the appended claims.

Claims

We claim:

1. A film-forming coating composition comprising:(a) a film-forming component; and(b) aluminum particles, wherein the weight % of aluminum particle solids on filmforming component solids is at least 50%.

2. The composition of claim 1, wherein the film-forming component comprises:(a) a resin component comprising epoxide functional groups; and(b) a curing agent component comprising amine functional groups.

3. The composition of any preceding claim, wherein the weight % of aluminum particle solids on film-forming component solids is 50% to 125%.

4. The composition of any preceding claim, wherein the aluminum particles comprise a D(50%) particle size of 5p to 55p.

5. The composition of any preceding claim, wherein the aluminum particles comprise leafing aluminum flakes and / or non-leafing aluminum flakes.

6. The composition of any preceding claim, wherein the composition is substantially-free of leafing aluminum flakes.

7. The composition of any preceding claim, wherein the aluminum particles consist essentially of non-leafing aluminum flakes.

8. The composition of any preceding claim, further comprising an additional corrosion inhibitor, such as a metal oxide.

9. The composition of any preceding claim, wherein the composition is a multi-component coating composition, wherein a film-forming resin is in one component and a curing agent is in a different component.

10. The composition of any preceding claim, wherein the coating composition is substantially free, essentially free, and / or completely free of a chromium (Vl)-containing material.

11. The composition of any preceding claim, wherein a coating layer deposited from said composition, when cured to a dry film thickness of lOp to 25 p, has a Delta E heat resistance of 5 or less as measured using the Heat Resistance Test.

12. The composition of any preceding claim, wherein a coating layer deposited from said composition, when cured to a dry film thickness of lOp to 25p, has a Delta E UV resistance of less than 4, such as 3 or lower, as measured according to the UV Resistance Test.

13. The composition of any preceding claim, wherein a coating layer deposited from said composition, when cured to a dry film thickness of lOp to 25 p, has a forward impact resistance of at least 501bs-in as measured according to the Impact Resistance Test.

14. A method for using the coating composition of any preceding claim to coat at least a portion of a substrate comprising applying the coating composition to at least a portion of the substrate.

15. A substrate coated in accordance with the method of claim 14.

16. The coated substrate of claim 15, wherein the substrate comprises a metal, a metal alloy, and / or a composite material.

17. The coated substrate of claim 16, wherein the metal alloy comprises aluminum such as a 2000, 3000, 4000, 5000, 6000, or 7000, series aluminum alloy, such as a 2024 aluminum alloy, a 2024-T3 aluminum alloy, a 7075 aluminum alloy, or a 6061 aluminum alloy.

18. The coated substrate of any of claims 15 to 17, wherein the coating layer forms part of a coating stack.

19. The coated substrate of any of claims 15 to 18, wherein the substrate comprises an aircraft part.

20. The coated substrate of any of claims 15 to 19, wherein the substrate comprises a three- dimensional component.