WO2024173284A1

WO2024173284A1 - Leafing additives for flake alignment in powder coatings and methods for making and applying the same

Info

Publication number: WO2024173284A1
Application number: PCT/US2024/015454
Authority: WO
Inventors: Troy James LARIMER
Original assignee: Ppg Industries Ohio, Inc.
Priority date: 2023-02-17
Filing date: 2024-02-13
Publication date: 2024-08-22

Abstract

Leafing additives for inducing flake alignment in powder coatings are provided. The additives may include an amphipathic material, an effect pigment, and polymeric resin particles. Substrates may be coated by contacting a least a portion of the substrate with the coating composition and curing the composition to form a coating layer. The coatings may impart a vibrant and sparkling appearance to the substrate.

Description

LEAFING ADDITIVES FOR FLAKE ALIGNMENT IN POWDER COATINGS AND METHODS FOR MAKING AND APPLYING THE SAME

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional Application No. 63/485,600 entitled “LEAFING ADDITIVES FOR FLAKE ALIGNMENT IN POWDER COATINGS AND METHODS FOR MAKING AND APPLYING THE SAME”, filed on February 17th, 2023, which is incorporated by reference in its entirety.

FIELD

[0002] The present disclosure relates to additives that induce leafing flake alignment in powder coating compositions, and methods for making and applying the same.

BACKGROUND

[0003] Powder coatings are solvent-free or reduced solvent coating systems used in a number of applications, including automotive coatings, household appliances, architectural and construction components, furniture, agricultural machinery, and electronics. Powder coatings are made of a thermosetting resin system and are typically applied to a substrate electrostatically and cured at elevated temperatures (e.g., at or above 300 °F).

[0004] Traditionally, in order to achieve a vibrant visual effect in the cured powder coating, effect pigments are used, which are typically particulates that reflect, refract, or transmit light to produce color variations such as luster, sparkle, and shimmer. For example, two-dimensional metallic effect pigments may include small, flat pieces of metal to reflect light and produce a luster.

SUMMARY

[0005] The present disclosure provides leafing additives for inducing flake alignment in powder coating compositions, and methods of using the compositions, making the compositions, and/or applying the compositions to a substrate. The coating compositions may comprise an amphipathic material, an effect pigment, and polymeric resin particles. Substrates may be coated by contacting a least a portion of the substrate with the coating composition and curing the composition to form a coating layer. The leafing additives interact with effect pigments when the coating composition is cured and create a brighter appearance and a higher flop index.

[0006] In a first case, a powder coating composition is provided where the powder coating composition can include an amphipathic material comprising from 0.0005 wt. % to 20 wt. % of a total weight of powder coating composition; effect pigment particles comprising from 0.1 wt.% to 10 wt.% of the total weight of the powder coating composition; and polymeric resin particles. In another case, a coated article is provided where the that coated article can include a substrate; and a powder coating layer applied to the substrate, the powder coating layer comprising an amphipathic material, polymeric resin particles, and effect pigment particles, wherein the effect pigment particles and the amphipathic material interact, forming a surface effect on a surface of the coated article. In a further case, A method of coating an article is provided where the method can include mixing an amphipathic material, polymeric resin particles, and effect pigment particles to form a powder coating composition and spray applying the powder coating composition to a surface of the article.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figs. 1A-1E provide images of a powder coating composition undergoing a curing process where each of the figures depict effect pigment particles rising to the surface of the curing composition over time.

[0008] Figs. 2A and 2B provide a cross section of a powder coating undergoing a curing process where Fig. 2A depicts a control coating and Fig. 2B depicts a coating with an additive.

DETAILED DESCRIPTION

[0009] Currently, leafing flakes are used in powder coatings to impart a vibrant sparkling appearance. Leafing flakes orient at the surface of a powder coating during the curing phase. This parallel orientation creates a relatively continuous metallic looking surface which results in a vibrant appearance. Flakes are often pre-treated with a surface treatment that may be incompatible with most powder coating resin chemistries. This incompatibility forces the flakes away from the powder binder to the surface of the film, thereby resulting in their parallel orientation. It could be advantageous to add an additive to the powder coating composition, instead of pre-treating the flakes. In addition to eliminating the need for extra pre-treating steps, such an additive would allow for the leafing of a higher proportion of flakes in a given powder coating, thereby giving the illusion of having more flake and more sparkle.

[0010] The developed additives and methods address this need by formulating an amphipathic additive directly into a powder coating. This material interacts with the flake when the powder melts, which can cause the flake to leaf to the surface giving a dramatic and vibrant appearance.

I. Definitions:

[0011] For purposes of the following detailed description, it is to be understood that the disclosure may assume various alternative variations and step sequences, except where expressly specified to the contrary. Moreover, other than in any operating examples, or where otherwise indicated, all numbers expressing, for example, quantities of ingredients used in the specification and claims are to be understood as being modified in all instances by the term “about”. Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties to be obtained by the present disclosure. 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 at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

[0012] Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the disclosure are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard variation found in their respective testing measurements.

[0013] Also, it should be understood that any numerical range recited herein is intended to include all sub-ranges subsumed therein. For example, a range of “1 to 10” is intended to include all sub-ranges between (and including) the recited minimum value of 1 and the recited maximum value of 10, that is, having a minimum value equal to or greater than 1 and a maximum value of equal to or less than 10. [0014] In this application, the use of the singular includes the plural and plural encompasses singular, unless specifically stated otherwise. In addition, in this application, the use of “or” means “and/or” unless specifically stated otherwise, even though “and/or” may be explicitly used in certain instances. Further, in this application, the use of “a” or “an” means “at least one” unless specifically stated otherwise. For example, “a” polymer, “a” pigment, “a” composition, “a” powder coating composition, “an” amphipathic material, “an” effect pigment, “a” polymeric resin particle, and the like refer to one or more of any of these items. [0015] “Amphipathic material” refers to molecule(s) and/or polymer(s) which has both hydrophilic and hydrophobic parts.

[0016] “Polymer” refers to oligomers, homopolymers (e.g., prepared form a single monomer species), copolymers (e.g., prepared form at least two monomer species), terpolymers (e.g., prepared from at least three monomer species), and graft polymers.

[0017] “Film forming resin” refers to a resin that may form a self-supporting continuous film on at least a horizontal surface of a substrate upon removal or any diluents or carriers.

[0018] 'Crosslinker" refers to a molecule comprising two or more functional groups that are reactive with other functional groups and that is capable of linking two or more monomers or polymers through chemical bonds.

[0019] “Colorants” refers to a pigment, tint, dye, or any other coloring material which is used to impart color or opacity to the powder coating composition per ASTM E284. As used herein, the term “colorant” differs from effect pigments.

[0020] “Effect pigment” refers to flake or plate-like structures that impart a directional light reflectance, scattering, absorption, or optically variable appearance to the substrate in or on which they are applied. Effect pigments may be used to produce coatings having flake appearances such as texture, sparkle, glint, coarseness, and glitter, as well as the enhancement of depth perception in the coatings imparted by the effect pigments.

[0021] “Substantially free of’ as used herein indicates that the composition contains the material in question in an amount of 0.5 wt.% or less, based on the entire weight of the composition.

II. Powder Coating Compositions

[0022] The powder coating compositions as described herein generally comprise at least an amphipathic material, an effect pigment, and polymeric resin particles. The powder coating compositions may also comprise other additives such as flow agents, colorants, stabilizers, degassing agents, antioxidants, hardening agents, waxes, and the like. The coating compositions may be applied and cured to form a coating layer on a variety of substrates to improve their appearance and provide a vibrant sparkling effect. Each of Sections i. through v. describe non-limiting examples of such suitable components of powder coating compositions.

[0023] The coating compositions may be layered underneath a powder overcoat which, as used herein, refers to an overcoat embodied in solid particulate form. The coating compositions may also be layered over top of a powder basecoat which, as used herein, refers to a basecoat embodied in solid particulate form. The coating composition may also be layered underneath or above a liquid overcoat, which may be formed by melting or otherwise liquidizing a powder overcoat. Multiple layers of coating compositions may be used to form multi-layer coatings. The coating compositions may be layered underneath a topcoat or series of topcoats, or above a base coat or series of base coats to form a stackup.

[0024] i. Resins

[0025] The coating compositions herein may comprise a binder or a film forming resin in one or multiple components. A “binder” refers to a constituent material that may hold all coating composition components together upon curing. The binder may comprise one or more film-forming resins that may be used to form the coating layer. As used herein, a “filmforming resin” refers to a resin that may form a self-supporting continuous film on at least a horizontal surface of a substrate upon removal or any diluents or carriers present in the composition and/or upon curing. The term “resin” is used here interchangeably with “polymer”. Film forming resins may be incorporated into components of the powder coating compositions as a liquid or as a solid. In the case of powder coating compositions, the binder (or film former) may be a polymeric powder material comprising polymeric particles.

[0026] The coating composition used with the present disclosure may include any variety of thermosetting powder compositions. As used herein, the term “thermosetting” refers to compositions that “set” irreversibly upon curing or crosslinking, wherein polymer chains of polymeric components are joined together by covalent bonds. This property is usually associated with a cross-linking reaction of the composition constituents often induced, for example, by heat or radiation. Once cured, a thermosetting resin will not melt upon the application of heat and is insoluble in solvents. The coating compositions used with the present disclosure may also include thermoplastic powder compositions. As used herein, “thermoplastic” refers to compositions that include polymeric components that are not joined by covalent bonds and, thereby, can undergo liquid flow upon heating.

[0027] Suitable film-forming resins include (meth)acrylate (e.g., acrylic) resins, polyurethanes, polyesters, polyamides, polyethers, poly siloxanes, epoxy resins, vinyl resins, copolymers thereof, and combinations thereof. As used herein, "(meth) acrylate" and like terms refers both to the acrylate and the corresponding methacrylate. Further, the filmforming resins may have any of a variety of functional groups including, but not limited to, carboxylic acid groups, amine groups, epoxide groups, hydroxyl groups, thiol groups, carbamate groups, amide groups, urea groups, isocyanate groups (including blocked isocyanate groups), and combinations thereof. Examples of suitable polyester-based resins include Uralac P5504: an alcohol functional polyester resin commercially available through DSM. Examples of suitable acrylic resins include Almatex PD6300: a glycidyl methacrylate based poxy functional acrylic resin commercially available through Anderson Development Company. Examples of suitable epoxy resins include NPES-903 : a medium molecular weight solid epoxy resin based on bisphenol A, commercially available from Nan Ya Plastics Corp. [0028] The coating compositions may comprise any number of film forming resins, such as one film forming resin, or two or more film forming resins. Any particular film forming resin or any combination of film forming resins may be present in the coating composition in an amount of as little as 20 wt. %, 25 wt.%, 30 wt. %, 35 wt. %, 40 wt. %, 45 wt. %, 50 wt.%, 55 wt. % or in an amount as great as 95 wt.% 90 wt. %, 85 wt. %, 80 wt. %, 75 wt. %, 70 wt. %, 65 wt. %, 60 wt. %, or any range including any two of these values as endpoints based on the total weight of the coating composition. Any particular film forming resin or combination of film forming resins may be present in the coating composition from 40 wt. % to 90 wt. %, from 40 wt. % to 85 wt. %, from 45 wt. % to 80 wt. %, from 50 wt. % to 80 wt. %, from 55 wt. % to 80 wt. %, from 55 wt. % to 75 wt. %, or from 60 wt. % to 70 wt. % based on the total weight of the coating composition or based on the weight of one component of the coating composition

[0029] ii. Crosslinkers

[0030] The coating compositions of the present disclosure may comprise a crosslinker in one or multiple components that may be selected from any of the crosslinkers known in the art to react with the functionality of one or more film-forming resins used in the coating composition. As used herein, the term "crosslinker" refers to a molecule comprising two or more functional groups that are reactive with other functional groups and that is capable of linking two or more monomers or polymers through chemical bonds. Alternatively, the filmforming resins that form the binder of the coating composition may have functional groups that are reactive with themselves; in this manner, such resins are self-crosslinking.

[0031] Suitable crosslinkers include phenolic resins, amino resins, epoxy resins, triglycidyl isocyanurate, beta-hydroxy (alkyl) amides, alkylated carbamates, (meth) acrylates, isocyanates, polyisocyanates, blocked isocyanates, polyacids, anhydrides, organometallic acid-functional materials, polyamines, polyamides, aminoplasts, carbodiimides, oxazolines, tetrakis(methoxymethyl)glycoluril, and combinations thereof. Examples of suitable crosslinkers include Vestagon BF1540: a uretdione functional polyisocyanate adduct commercially available through Evonik.

[0032] Any particular crosslinker or any combination of crosslinkers may be present in the coating composition in an amount of as little as 0.1 wt. %, 0.5 wt. %, 1 wt. %, 2 wt. %, 3 wt. %, 4 wt. %, 5 wt. %, 6 wt. %, 7 wt. %, 8 wt. %, 9 wt. %, 10 wt. %, 15 wt. %, 20 wt. %, 25 wt. % or in an amount as great as 50 wt. %, 45 wt. %, 40 wt. %, 35 wt. %, 30 wt. %, or any range including two of these values as endpoints based on the total weight of the coating composition. Any crosslinker or combination of crosslinkers may be present in an amount from 0.5 wt. % to 10 wt. %, from 0.5 wt. % to 8 wt. %, from 0.5 wt. % to 6 wt. %, from 0.5 wt. % to 5 wt. %, from 1 wt. % to 5 wt. %, from 1 wt. % to 4 wt. %, or from 1 wt. % to 2 wt. % based on the total weight of the coating composition or based on the weight of one component of the coating composition.

[0033] iii. Amphipathic Materials

[0034] The coating compositions of the present disclosure may include an amphipathic material to help facilitate the leafing of effect pigments. The term “amphipathic” as used herein refers to a molecule or polymer which has both hydrophilic and hydrophobic parts. It has been surprisingly found that these materials promote a leafing effect in powder coatings without the need to pre-treat effect pigments.

[0035] Without being bound to any theory, it is believed that the hydrophilic portion of the amphipathic material attaches to the effect pigment, and the hydrophobic portion of the amphipathic material migrates to the surface. This migration results in many desirable surface effects.

[0036] Figs. 1A-1E provide chronological images 100, 106, 112 ,118, and 124 of a powder coating with effect pigment being cured. Paying special attention to areas 102, 104, 108, 110, 114, 116, 120, 122, 126, and 128, the flakes in the coating begin to leaf and become more visible as they rise to the surface. Particularly, each of areas 102, 108, 114, 120, and 126 represent a first same area of the powder coating, and each of areas 104, 110, 116, 122, and 128 represent a second same area of the powder coating, whereas the effect pigments become more clearly visible over time, indicating that the effect pigments have risen towards the surface of the coating (e.g., leafed).

[0037] Articles coated with coating compositions including amphipathic materials have a lower surface energy as compared to the same coating compositions without amphipathic materials. Specifically, the surface energy of coated articles including the amphipathic material may be as little as 10 mJ/m², 15 mJ/m², 16 mJ/m², 17 mJ/m², 18 mJ/m², 20 mJ/m², or 25 mJ/m2, or as high as 35 mJ/m², 40 mJ/m², 45 mJ/m², 46 mJ/m², 47 mJ/m², 48 mJ/m², 50 mJ/m², or 55 mJ/m², or any value between any of the forgoing values as endpoints, as measured by ASTM D7490-13. Accordingly, the surface energy may drop by as little as 15 mJ/m², 20 mJ/m², or 25 mJ/m², or as much as 30 mJ/m², 31 mJ/m² 32 mJ/m², 33 mJ/m², 35 mJ/m², or 40 mJ/m², or by amount between any of the foregoing values as endpoints, as compared to the surface energy of the same powder coating composition without the addition of the amphipathic material.

[0038] Articles coated with a coating composition including the amphipathic material may also exhibit higher brightness (e.g., L*) values, as compared to coating compositions without amphipathic materials, as a result of more of the effect pigment flakes rising to the surface of the cured coating. In these cases, the brightness (L*) value may be as low as 1.0, 10.0, 20.0, 30.0, 50.0, 60.0, or 70.0, or as high as 75.0, 79.0, 80.0, 81.0, or 85.0, 90.0, 100.0, 125.0, 150, 200, 250, 300, 400, or 500, or any value between the forgoing values, as measured by DIN EN ISO 11664. In this case, the L* values for coating compositions include the amphipathic material may increase anywhere from 5 to 300 L* units, such as 5-100 L* units, as based upon an article coated with a powder coating composition without the amphipathic material. The higher brightness value may indicate that as little as 1%, 5%, 10%, 15%, or 20 % or as high as 25%, 28%, 30%, 31%, 32%, 36%, or 40%, or any value between the forgoing values as endpoints, of the effect pigment flakes rose to the surface of the coated article based upon the inclusion of the amphipathic material.

[0039] Articles coated with a coating composition including the amphipathic material also exhibit a low gloss value, which may result from the amount of effect pigment added to the powder coating composition. Specifically, the powder coating composition including the amphipathic material may have a gloss value (GU), as measured at 60 degrees and per to ISO 2813 and ASTM D523.4, as low as 15, 20, or 25, or as high as 75, 80, 85, or 90, or any value between the forgoing values, which may result in a gloss value decrease of anywhere between 15 and 150 GU. Particularly, gloss values may decrease between 60 and 70 GU. [0040] To promote this migration and the resulting vibrant effect in the cured coatings, any molecule or polymer with a hydrophobic and hydrophilic portion could be used. [0041] In this case, amphipathic materials that include amine functional groups, amine and methoxy functional groups, carboxylic acid and hydroxyl functional groups, and amine-alkoxy functional groups have been found to be particularly suitable to promote vibrate leafing effects when added to the powder coating composition. Suitable examples of amphipathic materials include siloxanes, functional siloxane such as amine-functional siloxanes, or methoxy functional siloxanes, fluorinated organic polymers, steric acid-based compounds, oleic acid-based compounds, and combinations thereof. Specifically, formulations of the General Formula I, and each of the specific Formulas II-V have been found to exhibit at least some suitable leafing effects.

General Formula I:

Formula II:

[0042] In Formula II, x and y may be integers from 1 to 500.

Formula III:

[0043] In Formula III, x may be an integer from 1 to 500.

Formula IV :

[0044] In Formula IV, x may be an integer from 1 to 500.

Formula V :

[0045] In Formula V, x may be an integer from 1 to 500.

[0046] Specifically, formulations of Siloxane-based amphipathic materials may include any of GP-657: an amine-alkoxy silicone fluid commercially available from Genesee Polymers, GP-367: a polar thiol functional polysiloxane polymer commercially available from Genesee Polymers, Dowsil 550 125cs: a phenylated polysiloxane polymer commercially available from DOW Chemicals, Gelest DMS-T22200cSt: a nonfunctional polysiloxane polymer commercially available from Gelest, and amine functional siloxanes which lack Alkoxy functionality (e.g., polar amine functional polysiloxane polymer containing no alkoxy groups). Suitable examples of fluorinated amphipathic materials include Krytox GPL grease/oil, a perfluoropolyether- (PFPE-) based oil manufactured by Krytox and Dynasylan 8261 manufactured by Palmer Holland. Suitable examples of amphipathic materials also include stearic acid and oleic acid.

[0047] Any particular amphipathic material or combination of amphipathic materials may be present in the powder coating composition in an amount as low as 0.0001 wt.%, 0.0005 wt.%, 0.001 wt.%, 0.01 wt.%, 0.01625%, 0.05 wt.%, 0.1 wt.%, 0.5 wt.%, 1 wt.%, 2 wt.%, 3 wt.%, 4 wt.%, 5 wt.%, 6 wt.%, 7 wt.%, 8 wt.%, 9 wt.%, 10 wt.%, or as great as 11 wt.%., 12 wt.%, 13 wt.%, 14 wt.%, 15 wt.%, 16 wt.%, 17 wt.%, 18 wt.%, 19 wt.%, 20 wt.%, 25 wt.%, 30 wt.%, or any range including any two of the foregoing values as endpoints, based on the total weight of the coating composition. Particularly, the amphipathic material may comprise from 0.0005 wt. % to 20 wt. %, 0.01625 wt. % to 2 wt. %, 0.5 to 2 wt. %, or 0.5 to 1.5 wt.% of the powder coating composition.

[0048] iv. Additives

[0049] The powder coating composition may further optionally comprise one or more additives known in the art. Such additives may include flow control agents, flow restricting agents, dry flow agents, antioxidants, pigments, colorants, optical brighteners, extenders, surface control agents, waxes, catalysts, reaction inhibitors, corrosion-inhibitors, conductivity enhancers, and combinations comprising at least one of the foregoing additives, and the like. [0050] Examples of suitable catalysts include Butaflow BT-71: a dibutylin dilaurate catalyst adsorbed onto silica, commercially available from Estron chemical.

[0051] The overcoat may also comprise a colorant. As used herein, "colorant" refers to any substance that imparts color and/or other opacity and/or other visual effect to the composition. The colorant may be added to the coating in any suitable form, such as discrete particles, dispersions, solutions, and/or flakes. A single colorant or a mixture of two or more colorants may be used in the coatings of the present disclosure.

[0052] Colorants include pigments (organic or inorganic), dyes and tints, such as those used in the paint industry and/or listed in the Dry Color Manufacturers Association (DCMA), as well as special effect compositions. A colorant may include a finely divided solid powder that is insoluble, but wettable, under the conditions of use. A colorant may be organic or inorganic and may be agglomerated or non-agglomerated. Colorants may be incorporated into the coatings by use of a grind vehicle, such as an acrylic grind vehicle, the use of which will be familiar to one skilled in the art.

[0053] Pigments and/or pigment compositions may include, but are not limited to, carbazole dioxazine crude pigment, azo, monoazo, diazo, naphthol AS, benzimidazolone, isoindolinone, isoindoline and polycyclic phthalocyanine, quinacridone, perylene, perinone, diketopyrrolo pyrrole, thioindigo, anthraquinone, indanthrone, anthrapyrimidine, flavanthrone, pyranthrone, anthanthrone, dioxazine, triarylcarbonium, quinophthalone pigments, diketo pyrrolo pyrrole red ("DPPBO red"), titanium dioxide, carbon black, and mixtures thereof. Examples of suitable pigments Regal 660 Black: a low structure specialty pelleted black pigment commercially available from Cabot Corp.

[0054] Pigments may include, but are not limited to, those that are solvent and/or aqueous based such as phthalo green or blue, iron oxide, bismuth vanadate, anthraquinone, and peryleneand quinacridone.

[0055] The powder coating composition may further optionally comprise flow control agents, sometimes called leveling agents, which are useful to promote the formation of a continuous and even coating. Suitable flow control agents include polyacrylic esters, nonionic fluorinated alkyl ester surfactants, non-ionic alkylarylpolyether alcohols, silicones, and the like, and combinations comprising at least one of the foregoing flow control agents. Flow control agents are generally liquids that have been converted to powder form by absorption onto silica-type materials. Examples of suitable flow control agents include 2-propenoic acid, ethyl ester polymer acrylic resin, available under the tradename RESIFLOW® P-67 by Estron Chemical, Inc. and 2-hydroxy-l,2-diphenylethanone which crystalline solid that is believed to keep the molten coating open for a suitable time to allow outgassing to occur prior to the formation of the hard-set film, sold under the tradename Benzoin by DSM, Inc. Resiflow PL200A, a low viscosity acrylic polymer adsorbed onto silica commercially available through Estron Chemical, may also be used as a leveling agent. The powder coating composition may also include a dry flow agent such as fumed silica such as the ones sold under the tradename AEROSIL® by Evonik Corporation.

[0056] Examples of suitable acrylic resins include Almatex PD6300: a glycidyl methacrylate basede poxy functional acrylic resin commercially available through Anderson Development Company.

[0057] Any particular additive or any combination of additives may be present in the coating composition in an amount of as little as 0.1 wt. %, 0.5 wt. %, 1 wt. %, 2 wt. %, 3 wt. %, 4 wt. %, 5 wt. %, 6 wt. %, 7 wt. %, 8 wt. %, 9 wt. %, 10 wt. %, or as great as 20 wt. %., 19 wt. %, 18 wt. %, 17 wt. %, 16 wt. %, 15 wt. %, 14 wt. %, 13 wt. %, 12 wt. %, 15 wt.%, 20 wt. %, 30 wt. %, 40 wt%, 50 wt. %, 55 wt. %, or any range including any two of these values as endpoints based on the total weight of the coating composition. V. Effect Pigments

[0058] As described herein, the powder coating compositions of the present disclosure may comprise one or more effect pigments. Effect pigments are typically defined as flake or plate like structures that impart a directional light reflectance, scattering, absorption, or optically variable appearance to the substrate in or on which they are applied. Effect pigments may be used to produce coatings having flake appearances such as texture, sparkle, glint, coarseness, and glitter, as well as the enhancement of depth perception in the coatings imparted by the pigments.

[0059] Examples of effect pigments can include, but are not limited to, light absorbing pigments, light scattering pigments, light interference pigments, light reflecting pigments, fluorescent or phosphorescent pigments, thermochromic pigment, photochromic pigment, and gonioapparent pigments. Metallic particles or flakes can be examples of such effect pigments. They can be particles or flakes with specific or mixed shapes and dimensions. The term “gonioapparent flakes,” “gonioapparent pigment” or “gonioapparent pigments” refers to effect pigments.

[0060] As used herein, reference to “effect” pigments is intended to include “metallic” pigments. Examples of metallic pigments include mica (including natural and synthetic mica), metal oxide (such as aluminum, bronze, copper, stainless steel and gold), and glass (such as borosilicate glass, barium titanate glass particles, soda lime glass particles, and metal oxide coated glass). Commercially available pigments include for example those referred to as Xirallic®, Dynacolor®, Mearlin®, Luxan®, Sunmica®, ST AND ART®, and the like pigment. For instance, suitable effect pigment flakes may include Mearlin 139X Mica flakes, which is a flake mica coating with titanium dioxide in a particle size range of 6-48 microns or Mearlin 193P which is a flake mica with a particle size range of 18-68.5 microns, both commercially available from BASF. Examples of suitable aluminum flakes include include PCA9155, PCU1000, and PCU3500 which are available from Eckart GmbH.

Examples of flakes with a surface treatment include Iriodin 96107, which is a flake mica with surface treatment in a particle size range of 8.7-33.7 microns, commercially available from Pigment Lab Tokyo. Examples of suitable mica flakes also include Symic PCE which is a synthetic mica with a particle size range of 3-21 microns, available from Eckart GmbH. Examples of glass flakes include Mearlin Firemist Violet 9G530L which is a TiO2 coated borosilicate glass flake with a particle size range of 52-188 microns, available from BASF. [0061] The powder coatings of the present disclosure may also be substantially free of pre-treated effect pigments. The term “pre-treated’" effect pigments as used herein refers to effect pigments that are conditioned or processed with a leaf producing agent such as stearic acid, palmitic acid, a volatilizable hydrocarbon. Without being bound to any theory, it is believed that the interaction of the amphipathic material and the non-treated effect pigments allows for effect pigments to rise to the surface of the coating layer, resulting in the enhanced surface effects. As described previously, the amount of effect pigments at the surface may as low as 1 wt.%, 5 wt.%, 10 wt.%, 15 wt.%, 20 wt.%, 25 wt.%, or as high as 30 wt.%, 35 wt.%, 40 wt.%, 45 wt.%, 50 wt.%, or within any range encompassed by any two of the foregoing values as endpoints. For example, the amount of effect pigments may be from 1 wt.% to 50 wt.%, 5 wt.% to 45 wt.%, 10 wt.% to 40 wt.%, 15 wt.% to 35 wt.%, or 20 wt.% to 30 wt.% The amount of effect pigments particles at the surface of the coating layer may be, particularly, 30 wt.% to 35 wt.% including 31 wt.%.

[0062] The powder coating compositions of the present disclosure may comprise as little as 0.1 wt. %, 0.5 wt. %, 2 wt. %, 4 wt. % or as high as 6 wt. %, 8 wt.%, or 10 wt. %, or any range including any two of these values as endpoints, as based on the total weight of the coating composition. Specifically, the amount of effect pigment particles may be 0.1 wt.% to 10 wt. %, 2 wt.% to 8 wt. %, 4 wt. % to 6 wt. %, or 5 wt. %.

VI. Substrates

[0063] The present disclosure relates to contacting at least a portion of a substrate with multi-component powder coating composition and curing the composition to form a coating layer.

[0064] The substrate according to the present disclosure can be selected from a wide variety of substrates and combinations thereof. Substrates may include vehicles and automotive substrates, industrial substrates, marine substrates and components such as ships, vessels, and on-shore and off-shore installations, storage tanks, packaging substrates, aerospace components, wood flooring and furniture, fasteners, coiled metals, heat exchangers, vents, an extrusion, roofing, wheels, grates, belts, conveyors, grain or seed silos, wire mesh, bolts or nuts, a screen or grid, HVAC equipment, frames, tanks cords, wires, apparel, electronic components, including housings and circuit boards, glass, sports equipment, including golf balls, stadiums, buildings, bridges, containers such as a food and beverage containers, and the like. As used herein, "vehicle" or variations thereof includes, but is not limited to, civilian, commercial and military aircraft, and/or land vehicles such as airplanes, helicopters, cars, motorcycles, and/or trucks. The shape of the substrate can be in the form of a sheet, plate, bar, rod or any shape desired.

[0065] The substrates, including any of the substrates previously described, can be metallic or non-metallic. Metallic substrates include, but are not limited to, tin, steel, cold rolled steel, hot rolled steel, steel coated with zinc metal, zinc compounds, zinc alloys, electrogalvanized steel, hot-dipped galvanized steel, galvannealed steel, galvalume, steel plated with zinc alloy, stainless steel, zinc-aluminum magnesium alloy coated steel, zincaluminum alloys, aluminum, aluminum alloys, aluminum plated steel, aluminum alloy plated steel, steel coated with a zinc-aluminum alloy, magnesium, magnesium alloys, nickel, nickel plating, bronze, tinplate, clad, titanium, brass, copper, silver, gold, 3-D printed metals, cast or forged metals and alloys, or combinations thereof.

[0066] Non-metallic substrates include polymeric, plastic, polyester, polyolefin, polyamide, cellulosic, polystyrene, polyacrylic, poly(ethylene naphthalate), polypropylene, polyethylene, nylon, EVOH, polylactic acid, other "green" polymeric substrates, poly (ethyleneterephthalate) (PET), polycarbonate, engineering polymers such as poly(etheretherketone) (PEEK), polycarbonate acrylobutadiene styrene (PC/ABS), polyamide, wood, veneer, wood composite, particle board, medium density fiberboard, cement, stone, glass, paper, cardboard, textiles, leather both synthetic and natural, composite substrates such as fiberglass composites or carbon fiber composites, 3-D printed polymers and composites, and the like.

VII. Coating Methods

[0067] The components of the powder coating compositions may be contacted through mixing, grinding, or any suitable contacting method. The components may be a solid at room temperature (e.g., around 23 °C) and more specifically may be a powder with an average particle size (e.g., diameter ranges from around 5 pm to 200 pm). The individual components may be contacted in any suitable ratio to form the coating composition.

[0068] The substrate may be preheated to a surface temperature or a bulk temperature before the application of the coating composition. The substrate may be heated to a surface temperature of as little as 100°F, 125°F, 150°F, 175°F, 200°F, or as great as 225°F, 250°F, 275°F, 300°F, 325°F, 350°F, 375°F, 400°F, or any range including any two of these values as endpoints. Stated differently, the substrate may be heated to a surface temperature of as little as 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, or as great as 120°C, 130°C, 140°C, 150°C, 160°C, 170°C, 180°C, 190°C, 200°C, 210°C or any range including any two of these values as endpoints. The substrate may be heated to a surface temperature from 40°C to 150°C, from 50°C to 150°C, from 60°C to 150°C, from 70°C to 150°C, from 80°C to 150°C, from 90°C to 150°C, from 100°C to 150°C, from 110°C to 150°C, from 110°C to 140°C, or from 120°C to 140°C.

[0069] Once the coating composition has been applied to the substrate, the coating is cured. The curable coating composition may be cured with heat, increased or reduced pressure, chemically such as with moisture, or with other means such as actinic radiation, and combinations thereof. Curing may comprise an initial curing step with radiation, followed by heating. The term “actinic radiation” refers to electromagnetic radiation that can initiate chemical reactions. Actinic radiation includes, but is not limited to, visible light, ultraviolet (UV) light, infrared (IR), X-ray, and gamma radiation.

[0070] The coating composition may be cured at a low temperature. The coating composition may be cured at less than 450°F, less than 425 °F, less than 400°F, less than 375°F, less than 350°F, less than 325°F, less than 300°F, less than 290°F, less than 280°F, less than 275 °F, less than 270°F, less than 260°F, less than 250°F, or any range including any two of these values as endpoints. Stated differently, the coating composition may be cured at less than 240°C, less than 230°C, less than 220°C, less than 210°C, less than 200°C, less than 190°C, less than 180°C, less than 170°C, less than 160°C, less than 150°C, less than 140°C, less than 130°C, less than 120°C, or any range including any two of these values as endpoints. The coating composition may be cured at a temperature from 120°C to 200°C, from 120°C to 190°C, from 120°C to 180°C, from 120°C to 170°C, from 120°C to 160°C, from 120°C to 150°C, from 120°C to 140°C, or from 120°C to 130°C.

[0071] The curing step may be carried out for any suitable time to allow the coating to fully or at least partially cure. The curing time may vary depending on the substrate, the coating composition, the coating thickness, ambient conditions, curing methods, or any combination of these factors. Curing time may be as little as 1 minute, 2 minutes, 3 minutes, 4 minutes, 5 minutes, 6 minutes, 7 minutes, 8 minutes, 9 minutes, 10 minutes, or as great as 60 minutes, 55 minutes, 50 minutes, 45 minutes, 40 minutes, 35 minutes, 30 minutes, 25 minutes, 20 minutes, 15 minutes, 12 minutes, or any range including any two of these values as endpoints. The curing time may be from 1 minute to 30 minutes, from 1 minute to 20 minutes, from 1 minute to 15 minutes, from 1 minute to 10 minutes, from 1 minute to 6 minutes, from 5 minutes to 15 minutes, from 5 minutes to 10 minutes, or from 3 minutes to 9 minutes.

[0072] The overall coating on the substrate may have a thickness of as little as 0. 1 mils, 0.2 mils, 0.3 mils, 0.4 mils, 0.5 mils, 0.6 mils, 0.7 mils, 0.8 mils, 0.9 mils, 1 mil, 1.5 mils, 2 mils, 2.5 mils or as great as 20 mils, 15 mils, 14 mils, 13 mils, 12 mils, 11 mils, 10 mils, 9 mils, 8 mils, 7 mils, 6 mils, 5 mils, 4 mils, 3.9 mils, 3.8 mils, 3.7 mils, 3.6 mils, 3.5 mils, 3.4 mils, 3.3 mils, 3.2 mils, 3.1 mils, 3 mils, or any range including any two of these amounts as endpoints. The overall coating may have a thickness of 1 mils to 4 mils, 1.5 mils to 2.5 mils, or 2 mils to 3 mils. The thickness may be measured according to the ASTM D7091-13 test method using and Elcometer 415 Model B Dual FNF film gauge.

[0073] Other application methods that can be used to apply the coating composition onto the substrate include: spraying, such as by incorporating the coating composition into a liquid formulation and using spray equipment; wiping where the coating composition is contained on and/or in a wipe and manually or automatically wiped; media blasting where the coating composition is a solid and is blasted onto the substrate's surface; electrostatically applied as a powder; brushing or rolling the coating composition over the substrate such as by incorporating the coating composition into a formulation ( e.g., liquid or gel) that can be brushed or rolled; vapor deposition; electrodeposition where the formulation is liquid and is electro-coated; or any combination thereof. The coating composition may also be applied inmold, during extrusion, during a calendaring, or during other processing of substrate materials.

[0074] The coating composition may be applied directly to a substrate without any intermediate layers between the coating composition and the substrate. The coating composition may be applied directly to a metal substrate, before or after the substrate is cleaned and/or treated as further described herein, but before application of any coating layers. The coating composition may also be applied during cleaning such as a component of the cleaner. The coating composition may be applied over the entire surface, edges, and corners of the substrate, or the coating composition may be applied over selected portions of the substrate.

[0075] The coating composition may also form a continuous or semi-continuous layer over the substrate, or the coating composition may be applied over certain spots/areas of the substrate such as the edges and comers of the substrate. As used herein, the area referred to as the "edge" will vary based on the particular substrate but may include, e.g., the outer most lateral face of the substrate.

[0076] The coating composition can be applied to the substrate to form a monocoat. As used herein, a "monocoat" refers to a single coating layer that is free of additional coating layers. Thus, the coating composition can be applied directly to a substrate and cured to form a single layer coating, i.e., a monocoat.

[0077] The coated substrate of the present disclosure may further comprise one or more additional coating layers, such as a second overcoat deposited onto at least a portion of the first coating composition, to form a multi-layer coating such as by applying a topcoat. When a multi-layer coating is formed, the first coating composition can be cured prior to application of additional overcoats, or one or more of the additional overcoats and the first coating composition can be cured simultaneously. It is appreciated that the second overcoat and additional overcoat can be in solid or liquid form. The coating compositions may be layered underneath a topcoat or series of topcoats to form a stackup.

VIII. Coated Substrate Properties

[0078] Substrates coated according to the present disclosure may have one or more improved properties and may address one or more issues known in the coating industry. The improved properties may be observed in comparison to other, previously known coating compositions.

[0079] The coated articles in accordance with the present disclosure may have a sparkle effect which can be measured using an imaging multi-angle spectrophotometer. [0080] According to measurements made with the spectrophotometer, the coated articles may have a sparkle grade of as low as 0.00, 1.00, 2.00, 3.00, 4.00, 5.00, 6.00, 7.00, 8.00, 9.00 or as high as 10.00, 11.00, 12.00, 13.00, 14.00, 15.00, or within any range encompassed by any two of the foregoing values as endpoints.

[0081] The sparkle grade measurement may be made at an illumination angle relative to the normal of a surface of the coated article of 15°.

[0082] The coated articles in accordance with the present disclosure may also have a flop index which is defined according to Equation 1 below:

2.69 (L'-L³)^{1 11} / (L²)⁰⁸⁶ (1) wherein: L¹ is CIELAB L* measured at the aspecular angle of 15° L² is CIELAB L* measured at the aspecular angle of 45°; L³ is CIELAB L* measured at the aspecular angle of 110°.

[0083] The flop index of the coated articles may be as low as 1, 2, 3, 4, 5, 6, 7, 8, 9 or as high as 10, 11, 12, 13, 14, 15 16, 17, 18, or within any range encompassed by any two of the foregoing values as endpoints. The coating may comprise a flop index of at least 2.

[0084] As described previously, the articles coated with coating compositions including amphipathic materials may have a lower surface energy as compared to the same coating compositions without amphipathic materials , which may result in a surface energy may drop by as little as 15 mJ/m², 20 mJ/m², or 25 mJ/m², or as much as 30 mJ/m², 31 mJ/m² 32 mJ/m², 33 mJ/m², 35 mJ/m², or 40 mJ/m², or by amount between any of the foregoing values as endpoints, as compared to the surface energy of the same powder coating composition without the addition of the amphipathic material.

[0085] Also as described previously, the articles coated with a coating composition including the amphipathic material may also exhibit higher brightness (e.g., L*) values, as compared to the same coating compositions without amphipathic materials, with the L* values increasing anywhere from 5-to 100 L* units, as compared to coating compositions lacking amphipathic materials.

[0086] Also as describe previously, articles coated with a coating composition including the amphipathic material also exhibit a low gloss value, which may result in a gloss value decrease up to 85 GU.

[0087] The present coating composition may be cured at less than 450°F, less than 425°F, less than 400°F, less than 375°F, less than 350°F, less than 325°F, less than 300°F, less than 290°F, less than 280°F, less than 275°F, less than 270°F, less than 260°F, less than 250°F, or any range including any two of these values as endpoints. Stated differently, the coating composition may be cured at less than 240°C, less than 230°C, less than 220°C, less than 210°C, less than 200°C, less than 190°C, less than 180°C, less than 170°C, less than 160°C, less than 150°C, less than 140°C, less than 130°C, less than 120°C, or any range including any two of these values as endpoints. The coating composition may be cured at a temperature from 120°C to 200°C, from 120°C to 190°C, from 120°C to 180°C, from 120°C to 170°C, from 120°C to 160°C, from 120°C to 150°C, from 120°C to 140°C, or from 120°C to 130°C. [0088] The present coating compositions may be resistant to corrosion as measured by a salt spraying test according to the methods set forth in ASTM Bl 17-19. The present coating composition when applied to a substrate may demonstrate less than 5 mm average scribe creepage after at least 100 hours, at least 200 hours, at least 300 hours, at least 400 hours, at least 500 hours, at least 600 hours, at least 700 hours, at least 800 hours, at least 1000 hours, at least 1500 hours, at least 2000 hours, at least 2500 hours, at least 3000 hours, at least 3500 hours, at least 4000 hours, at least 4500 hours, at least 5000 hours.

[0089] The present coating compositions may have a low surface resistivity as measured by ANSI/ESD STM 4.1-2017. The present coating compositions when applied to a substrate may demonstrate a surface resistivity of as little as 100 ohms/square, 200 ohms/square, 300 ohms/square, 400 ohms/square, 500 ohms/square, 600 ohms/square, 700 ohms/square, 800 ohms/square, 900 ohms/square, 1000 ohms/square, 2000 ohms/square, 3000 ohms/square, 4000 ohms/square, 5000 ohms/square, 6000 ohms/square, 7000 ohms/square, 8000 ohms/square, 9000 ohms/square, 10,000 ohms/square, or as great as 50,000 ohms/square, 100,000 ohms/square, 500,000 ohms/square, 1,000,000 ohms/square, 10,000,000 ohms/square or any range including any two of these values as endpoints. The coating composition may have a surface resistivity of from 100 ohms/square to 1,000,000 ohms/square, from 200 ohms/square to 500,000 ohms/square, from 300 ohms/square to 100,000 ohms/square, from 400 ohms/square to 50,000 ohms/square, or from 500 ohms/square to 10,000 ohms/square.

EXAMPLES

Example A: Preparation of Curable Coating Compositions

[0090] Two curable coating compositions were prepared from the components listed in Table 1.

TABLE 1

Mass Breakdown of Curable Coating Compositions

[0091] Each of the components listed in Table 1 for Compositions 1, 2, and 3 were weighed in a container and mixed in a prism high speed mixer for 30 seconds at 2500 RPM to form a dry homogeneous mixture. The mixture was then melt-mixed in a Werner Pfleiderer 19 mm twin screw extruder with an aggressive screw configuration and a speed of 500 RPM. The first zone was set to 50°C, and the second, third, and fourth zones were set to 120°C. The feed rate was such that a torque of 30-45% was observed on the equipment. The mixtures were dropped onto a set of chill rolls to cool and re-solidify the mixtures into solid chips.

[0092] The chips were milled in a Mikro ACM- 1 Air Classifying Mill to obtain an average particle size of 30 microns and a range of 10 microns to 100 microns. The particle size was determined by using the LS 13 320 Particle Size Analyzer from Beckman Coulter. The resulting coating compositions for each of Compositions 1-3 were solid particulate powder coating compositions that were free flowing.

TABLE 2

Powder Coating Composition Formulations

[0093] Each of the components listed in Table 2 for Examples 3-8 were weighed in a container and mixed in a shaken for 30 seconds to form a dry homogeneous mixture. Examples 4 and 6 were bonded using a Resodyne Acoustic Mixer. The materials were vibrated at 30 g’s and at temperature setpoint of 62°C. The mixtures were considered bonded when more than 5% of the material clumped and could be sieved out. Although Mica flake including titanium dioxide was used in Table 2, similar interactions and/or effects are expected for most flake particles and including aluminum flake and borosilicate glass flakes.

Example B: Application and Testing of Leafing in Powder Coatings

[0094] Examples 3-8 were electrostatically applied onto C700C59 zinc phosphate steel panels at an average filmbuild of 2.2 mils. The coatings were baked at 191 °C for 20 minutes.

[0095] The coated panels’ color was evaluated using a BYK-mac Metallic Color Multiangle Spectrophotometer from BYK. The L* values were measured according to DIN EN ISO 1166, and are presented in the table 3 below. The coated panel’s 60 degree gloss values were evaluated using a Rhopoint IQ glossmeter from Rhopoint. The gloss values (GU) were measured according to ISO 2813 and ASTM D523. 4, and are also presented in the table 3 below. A high L value when using mica flake is well known to indicate leafing and flake alignment.

[0096] The coated panels’ color was evaluated using a BYK-mac Metallic Color Multiangle Spectrophotometer from BYK. The L values are in Table 3 below. A high L value when using mica flake is well known to indicate leafing and flake alignment. TABLE 3

Evaluation of Degree of Leafing in Coatings

[0097] It is observed that more flake is likely applied to a panel from a bonded sample, which results in a higher L value. However, L values are consistently higher when using the siloxane than without. When bonded, a constant amount of flake and powder is applied to the panel, so the appearance effect of electrostatics is mitigated. The comparison between Examples 4 and 6 show how the leafing additive increases the L value in the coating from the flakes moving to the surface. The gloss values are greatly decreased in the examples containing the siloxane leafing additive. This low gloss is formed when leafed flake at the surface disrupts the reflecting light from the coating.

Example C: Evaluation of Amphipathic Material Loading Levels

[0098] Examples 7-10 were prepared using the above-described methods, but the mica was bag shaken in rather than bonded.

TABLE 4

Mass Breakdown of Curable Coating Compositions

[0099] Color readings shown below in Table 5 show a non-limiting wide range of useable amphipathic material loading levels to achieve flake leafing:

TABLE 5

Amphipathic Material Loading Levels

Example D: Determination of Materials that Generate Leafing

[00100] Several formulations were created by using the base extrudate chip from example 1. The additive and mica were post-added, followed by ACM milling to achieve an average particle size of ~30 microns.

TABLE 6

Mass Breakdown of Formulations with Base Extrudate Chip from Example 1

[00101] The materials were applied using the conventional methods described in the previous examples and the coatings’ appearance is described in Table 7 below.

TABLE 7

Appearance of Formulations with Base Extrudate Chip from Example 1

[00102] Table 7 shows that increasingly amphipathic materials may cause flake leafing. Materials with non-polar groups along the nonpolar siloxane display limited leafing, while materials with polar functional groups on a nonpolar siloxane display leafing. The material leeches out of the coating and onto the outside of the flake whose outer surface then has a lower surface energy. This causes the flake to migrate to the surface. Example E: Powder Coating Compositions with Different Flakes

TABLE 8

Formulations with Base Extrudate Chip from Example 1 and Different Flakes

[00103] Each of the components listed in Table 8 for Examples 19-30 were weighed in a container and mixed in a shaken for 30 seconds to form a dry homogeneous mixture. The materials were vibrated at 30 g’s and at temperature setpoint of 62°C. The mixtures were considered bonded when more than 5% of the material clumped and could be sieved out.

Example F: Analysis of Leafing for Coating Compositions with Different Flakes

[00104] Examples 19-30 were electrostatically applied onto C700C59 zinc phosphate steel panels at an average filmbuild of 2.2 mils. The coatings were baked at 191°C for 20 minutes.

[00105] The coated panels’ color was evaluated using a BYK-mac Metallic Color Multiangle Spectrophotometer from BYK. The L* values were measured according to DIN EN ISO 1166, and are presented in Table 9 below. A high L value when using mica flake is well known to indicate leafing and flake alignment.

[00106] The coated panels’ color was evaluated using a BYK-mac Metallic Color Multiangle Spectrophotometer from BYK. The L values are in Table 9 below. A high L value when using mica flake is well known to indicate leafing and flake alignment.

TABLE 9

Evaluation of Degree of Leafing in Coatings

Example G: Powder Coating Compositions with Different Flakes

TABLE 10

Formulations with Base Extrudate Chip from Example A and Different Flakes

[00107] Each of the components listed in Table 10 for Examples 31-36 were weighed in a container and mixed in a shaken for 30 seconds to form a dry homogeneous mixture. The materials were vibrated at 30 g’s and at temperature setpoint of 62°C. The mixtures were considered bonded when more than 5% of the material clumped and could be sieved out.

Example H: Analysis of Leafing for Coating Compositions with Different Flakes

[00108] Examples 31-36 were electrostatically applied onto C700C59 zinc phosphate steel panels at an average filmbuild of 2.2 mils. The coatings were baked at 191 °C for 20 minutes.

[00109] The coated panels’ color was evaluated using a BYK-mac Metallic Color Multiangle Spectrophotometer from BYK. The L* values were measured according to DIN EN ISO 1166, and are presented in Table 11 below. T A high L value when using mica flake is well known to indicate leafing and flake alignment.

[00110] The coated panels’ color was evaluated using a BYK-mac Metallic Color Multiangle Spectrophotometer from BYK. The L values are in Table 11 below. A high L value when using mica flake is well known to indicate leafing and flake alignment.

TABLE 11

Evaluation of Degree of Leafing in Coatings

Example I: Formulation and Evaluation of Coatings Containing Fluoropolymers [00111] In Example I, the polyester chips from Example A were combined with a fluoropolymer and tested for degree of leafing according to the same methods described in Examples A, G and H above.

TABLE 12

Evaluation of Leafing for Coatings with Fluoropolymer

Example J: Surface Energy of Coatings [00112] In Example J, the polyester chips from Example A were combined with an amphipathic material additive and flakes and tested for surface energy according to ASTM D7490-13.

TABLE 13

Surface Energy Measurements for Coatings

Example K: Coating with Oleic Acid

[00113] In Example K, the polyester chips from Composition 2 in Example A were combined with an amphipathic material additive and flakes and tested for surface energy according to ASTM D7490-13.

[00114] The results are summarized below in Table 14.

TABLE 14

Leafing Effects with Oleic Acid

Example L: Scanning Electron Microscopy of Leafing Coatings

[00115] An evaluation of leafing in coatings containing amine-alkoxy functional siloxane was done using a scanning electron microscope. Comparison was done with a cured coating of Composition 2 from Example A versus the control, a cured coating of Composition 1 from Example A.

[00116] Fig. 2A shows the cross section of the control and Fig. 2B shows the cross section of the inventive composition comprising the siloxane additive. Referring to Fig. 2A and 2B, 130 illustrates flakes which demonstrate less leafing than the flakes shown by 132. The number of flakes in each cross section at the surface of the coating and in the bulk was tabulated. Statistically significant increase of flake at the surface was observed in the coating comprising the siloxane additive compared to the control. The Surface Flake/Total Flake in coating = 0.30 (amphipathic material) vs. 0.18(control) >ltl = 0.0145.

Example M: Coating with Stearic Acid

[00117] In Example M, the polyester chips from Composition 2 in Example A were combined with an amphipathic material additive and flakes and tested for surface energy according to ASTM D7490-13.

[00118] The results are summarized below in Table 15.

TABLE 15

Leafing Effects with Stearic Acid

Claims

CLAIMS What is claimed is:

1. A powder coating composition comprising: an amphipathic material comprising from 0.0005 wt. % to 20 wt. % of a total weight of powder coating composition; effect pigment particles comprising from 0.1 wt.% to 10 wt.% of the total weight of the powder coating composition; and polymeric resin particles.

2. The powder coating composition of claim 1, wherein the amphipathic material comprises from 0.5 to 1.5 wt. % of the total weight of the powder coating composition.

3. The powder coating composition of either of claims 1 or 2, wherein the effect pigment particles comprise from 4.0 wt. % to 6.0 wt. % of the total weight of the powder coating composition.

4. The powder coating composition of any one of claims 1 through 3, wherein the amphipathic material comprises a siloxane material.

5. The powder coating composition of claim 4, wherein the siloxane material comprises an amine functional siloxane.

6. The powder coating composition of claim 5, wherein the siloxane material comprises an amine and methoxy functional siloxane.

7. The powder coating composition of any one of claims 1 through 6, wherein the amphipathic material comprises steric acid and/or oleic acid.

8. The powder coating composition of any one of claims 1 through 7, wherein the amphipathic material comprises a fluorinated organic polymer.

9. The power coating composition of claim 8, wherein the fluorinated organic polymer comprises a carboxylic acid functional group and a hydroxyl functional group.

10. The powder coating composition of any one of claims 1 through 9, wherein the effect pigment particles comprise aluminum flakes.

11. The powder coating composition of any one of claims 1 through 10, wherein the effect pigment particles comprise mica flakes.

12. The powder coating composition of any one of claims 1 through 11, wherein the effect pigment particles comprise untreated flakes of effect pigment particles.

13. The powder coating composition of any one of claims 1 through 12, wherein the polymeric resin particles comprise polyester-based resin particles.

14. The powder coating composition of any one of claims 1 through 13, wherein the polymeric resin particles comprise acrylic -based resin particles.

15. A coated article comprising: a substrate; and a powder coating layer applied to the substrate, the powder coating layer comprising an amphipathic material, polymeric resin particles, and effect pigment particles, wherein the effect pigment particles and the amphipathic material interact, forming a surface effect on a surface of the coated article.

16. The coated article of claim 15, wherein the surface effect comprises an increase in a surface brightness from 5 L value units to 100 L value units, as measured by DIN EN ISO 11664.

17. The coated article of either of claims 15 or 16, wherein the surface effect comprises a surface energy value from 15 mJ/m to 50 mJ/m², as measured by ASTM D7490-13.

18. The coated article of any one of claim 15 through 17, wherein the surface effect comprises a 60 degree gloss value decrease from 90 GU to 15 GU, as measured by ISO 2813 and ASTM D523.

19. The coated article of any one of claims 15 through 18, wherein the effect pigment particles interact with the amphipathic material to cause more than 25% of the effect pigment particles to rise to the surface of the coating layer.

20. The coated article of anyone of claims claim 15 to 19, wherein the powder coating layer is formed from the composition of any one of claims 1 to 14.

21. A method of coating an article comprising: mixing an amphipathic material, polymeric resin particles, and effect pigment particles to form a powder coating composition; and spray applying the powder coating composition to a surface of the article.

22. The method of claim 21, further comprising heating the powder coating composition to a glass transition temperature, bonding the effect pigment particles, and the powder coating.

23. The method of either of claims 21 or 22, wherein the powder coating composition comprises the powder coating composition of any one of claims 1 to 14.