Powder coating composition with application smoothness and sharp edge flow restriction

Abstract

A powder coating composition with a viscosity and cure profile optimized for good leveling while maintaining improved edge coverage of laser-cut materials as well as good smoothness and high gloss, and a method of preparing and applying the powder coating composition. The powder coating composition includes a thermosetting resin system, a catalyst, and a thermoplastic that has hydrogen bonding capabilities towards the thermosetting resin system.

Description

POWDER COATING COMPOSITION WITH APPLICATION SMOOTHNESS AND SHARP EDGE FLOW RESTRICTIONFIELD OF INVENTION

[0001] The present invention relates to a powder coating composition with a viscosity and cure profile optimized for good leveling while maintaining improved edge coverage of laser-cut materials as well as good smoothness and high gloss, and methods of preparing and applying the powder coating composition.BACKGROUND

[0002] Powder coatings are often used to coat metal substrates. There are many benefits to using powder coatings versus conventional paint, such as the ability to provide a durable finish having a smooth finish. However, when a metal substrate is laser cut, the cut edge is inevitably sharp and difficult to coat in a manner that achieves the same coverage, durability, smoothness, and glossiness as the other surfaces of the substrate.

[0003] Efforts by others have been made to address the difficulty of applying powder coatings to laser-cut edges of metal substrates, but each of the known compositions and techniques includes drawbacks. For example, an edge pretreatment can be applied to laser-cut edges prior to applying a powder coating composition. While the pretreatment can provide good smoothness and edge coverage performance, the application of the pretreatment is an extra step that could be avoided if the powder coating composition itself were improved.

[0004] There are also thermosetting resins and rheology modifiers that can be used to solve edge coverage problems, but these compositions do not achieve the same level of smoothness as conventional powder coating compositions applied to planar surfaces.

[0005] Some thermoplastics can improve powder coating application along cut edges, but these thermoplastics do not allow for a high gloss finish.

[0006] Production equipment is available that can be used to improve particle size distribution of a powder coating without altering the powder coating formulation.However, such equipment is expensive and, just like the application of the pretreatment, using this equipment is an extra step that could be avoided if the powder coating composition itself were improved.

[0007] It is an object of the present invention to provide a powder coating composition designed to effectively coat metal substrates, including laser-cut edges of metal substrates, while also providing smoothness and a high gloss finish. It is a further object of the invention to provide such a powder coating composition that does not require special equipment or processes for application.

[0008] It is yet another object of the invention to provide methods of preparing and applying such a powder coating composition.SUMMARY

[0009] These objects are achieved by the compositions and methods according to the present invention. A powder coating composition, in accordance with the invention, includes a thermosetting resin system, a catalyst, and a thermoplastic that has hydrogen bonding capabilities towards the thermosetting resin system.

[0010] The thermosetting resin system suitably includes at least one of the following: a carboxyl functional polyester crosslinked with triglycidyl isoctanurate (TGIC), a carboxyl functional polyester crosslinked with epoxide functional bisphenol A diglycidyl ether (DGEBA) style resin, a carboxyl functional polyester crosslinked with hydroxyl alkyl amide (HAA), a hydroxyl functional polyester crosslinked with a multifunctional isocyanate, a carboxyl functional polyester crosslinked with an epoxide functional acrylic resin, and a carboxyl functional acrylic resin crosslinked with an epoxide functional DGEBA style resin. For example, the thermosetting resin system may include a carboxyl functional polyester with acid value between 25 and 70 with a stoichiometric ratio for carboxyl: epoxide between 0.9 and 1.2 using TGIC as a crosslinking agent.

[0011] The catalyst in the powder coating composition is suitably present in a concentration that achieves a gel time between 5 and 200 seconds at 200°C for a final product of the powder coating.

[0012] The thermoplastic has a chemical composition that allows compatibility with the thermosetting resin system, ideally with the thermoplastic possessing intrinsic antistatic properties. In particular, the thermoplastic should be compatible enough with the thermosetting resin system to allow greater than 85 60° gloss in an absence of matting agents. For example, the thermoplastic may be a polyamide or a polyester, or a copolymer containing these functionalities, or a combination of a polyamide and a polyester and / or copolymers containing these functionalities.

[0013] The powder coating composition may also include one or more of the following: a pigment, a filler, a degassing agent, a flow additive, a leveling additive, and a rheology modifier.

[0014] Once the powder coating composition has been formed, the composition can be applied to a properly prepared metallic substrate and then cured on the substrate. The composition provides high gloss and smooth coverage, even on laser-cut edges of the substrate, as evidenced by performing ASTM D5162-21 Test Method A at a specified minimum coating thickness, which results in no indication of holidays on the edges of the substrate.

[0015] The powder coating composition can be prepared and applied using conventional production equipment. Also, existing powder coatings can be easily reformulated to result in the powder coating composition in order to impart the desired properties. Thus, the desired results can be achieved without the customer having to invest in extensive training or manufacturing changes.BRIEF DESCRIPTION OF THE DRAWINGS

[0016] FIG. 1 is a series of four photographs showing two panels treated with a conventional powder coating after undergoing corrosion testing and two panels treated with a powder coating composition in accordance with the invention after undergoing corrosion testing.

[0017] FIG. 2 is a series of four photographs showing two panels treated with a conventional powder coating after undergoing corrosion testing and two panels treatedwith a powder coating composition in accordance with the invention after undergoing corrosion testing.

[0018] FIG. 3 is a series of four photographs showing two panels treated with a conventional powder coating after undergoing corrosion testing and two panels treated with a powder coating composition in accordance with the invention after undergoing corrosion testing.

[0019] FIG. 4 is a series of four photographs showing one panel treated with a conventional powder coating after undergoing corrosion testing and two panels treated with a powder coating composition in accordance with the invention after undergoing corrosion testing.

[0020] FIG. 5 is a cross-sectional view via scanning electron microscope of traditional high gloss polyester-TGIC powder coating sprayed onto laser cut steel.

[0021] FIG. 6 is a cross-sectional view via scanning electron microscope of traditional high gloss polyester-TGIC powder coating modified with Platamid 1937 sprayed onto laser cut steel.

[0022] FIG. 7 is a graph showing particle size distribution curves for two different superdurable polyester-TGIC powders modified with the Platamid 1937 additive versus a control superdurable polyester-TGIC powder.DETAILED DESCRIPTION

[0023] Compositions and methods described herein solve the problem of providing a powder coating composition that can be applied to sharp edges while maintaining smoothness, high gloss, and sufficient thickness. The powder coating composition includes a primary thermosetting resin and appropriate crosslinker, combined with a thermoplastic component that improves powder application without losing the ability to have a smooth, high-gloss finish.

[0024] The thermosetting resin system may be an existing powder coating composition. As used herein, the term “existing powder coating composition” refers to a commercially-available powder coating composition that is ready to be applied to asubstrate. Examples of existing powder coating compositions include carboxyl functional polyester-TGIC, carboxyl functional polyester-HAA, carboxyl functional polyester-epoxy, hydroxy functional polyester-isocyanate, and hydroxy functional acrylic-isocyanate powder coatings. One of the benefits of the invention is that it is relatively easy to reformulate existing powder coatings, namely thermosetting resin powder coatings, to impart the desired properties rather than preparing a brand new powder coating composition from scratch. By simply reformulating existing powder coatings, the end user does not require much additional training or manufacturing changes in order to achieve the desired results of good edge coverage, smoothness, and a high-gloss finish. Also, reformulating existing powder coatings allows the manufacturer to achieve a product having the desired results without additional investment in equipment.

[0025] While existing powder coatings can be reformulated to achieve the powder coating composition of the invention, it is also possible to formulate a brand new powder coating composition from scratch in accordance with the invention. Suitable examples of the thermosetting resin system include the following, many of which are included in existing powder coatings: a carboxyl functional polyester crosslinked with TGIC, a carboxyl functional polyester crosslinked with epoxide functional DGEBA style resin, a carboxyl functional polyester crosslinked with hydroxyl alkyl amide, a hydroxyl functional polyester crosslinked with a multifunctional isocyanate, a carboxyl functional polyester crosslinked with an epoxide functional acrylic resin, and a carboxyl functional acrylic resin crosslinked with an epoxide functional DGEBA style resin. For example, superdurable or standard durable polyester TGIC may be used as the thermosetting resin system. More particularly, the thermosetting resin system may include a carboxyl functional polyester with acid value between 25 and 70 with a stoichiometric ratio for carboxyl: epoxide between 0.9 and 1 .2 using TGIC as a crosslinking agent. The thermosetting resin system accounts for between 40% and 90%, or between 60% and 70% by weight of the resulting powder coating composition.

[0026] Combining a selected thermoplastic component with the thermosetting resin system provides a variety of benefits. For example, the addition of the thermoplastic component increases the toughness of the chip state to allow tighter particle sizedistributions. As a result, with a mean particle size between about 20 and about 60 micrometers, the particle size distribution in a powder coating composition containing the thermoplastic component is narrower than powder coating compositions without the thermoplastic component. Additionally, the selected thermoplastic component has inherent anti-static properties that reduce the final powder formula surface resistivity to between 108-1013Q cm when built to 8 mils. The selected thermoplastic component is compatible with the primary thermosetting resin, which allows high gloss finishes attributable to the hydrogen bonding capabilities of the thermoplastic component with the thermosetting resin system. Another benefit resulting from the addition of the thermoplastic component is an increased viscosity in the resulting powder coating composition, which allows proper flow restriction.

[0027] The thermoplastic component, or thermoplastic resin, may account for 1 to 15 wt%, or 3 to 10 wt%, of the powder coating composition. The thermoplastic has a chemical composition that allows compatibility with the thermosetting resin system, ideally with the thermoplastic possessing intrinsic anti-static properties. In particular, the thermoplastic should be compatible enough with the thermosetting resin system to allow a value of greater than 85 on a 60° gloss measurement in an absence of matting agents. The thermoplastic component may be a polyamide or a polyester, or a combination of a polyamide and a polyester, with a viscosity of at least 5000 mPa*s at 200°C, and a Tg less than 60°C with a melting point between about 70 and about 130°C. Specific examples of suitable thermoplastic materials include polyureas, such as Platamid H 1937, available from Arkema Inc. of King of Prussia, Pennsylvania. Other thermoplastics can improve powder coating applications, but without providing a high gloss finish.

[0028] Catalysts that may be included in the powder coating composition are, for example, imidizoles, tertiary amine catalysts, ionic liquids, bases, and metal salts. Combinations of catalysts may also be used. These catalysts, collectively, may account for 0.01 % to 2% by volume, or 0.05% to 0.2% by volume of the powder coating composition. The catalyst is suitably present in a concentration that achieves a gel time less than 200 seconds at 200°C for a final product of the powder coating.

[0029] The powder coating composition may also include additives standardly used in powder coatings. Additives that may be included in the powder coating composition are, for example, pigments, fillers, degassing agents, flow additives, leveling additives, and rheology modifiers. Combinations of additives may also be used. These additives, collectively, may account for 0% to 70% by weight, or 5% to 35% by weight of the powder coating composition. For example, the pigment loading may be between about 0 and about 30 wt% or between about 1 and about 15 wt%, while the filler loading may be between about 0 and about 50 wt% or between about 10 and about 20 wt%. Examples of suitable pigments include carbon black, titanium dioxide and various metal oxides, while examples of suitable fillers include barium sulfate, calcium carbonate, and aluminum trihydrate. The degassing agent may be a benzoin degassing agent at a level between about 0.5 and about 1 .2 wt%. The flow additive and the leveling additive loading each may be between about 0.5 and about 1 .5 wt%. Examples of suitable flow additives and leveling additives include acrylic or silicone containing polymers deposited on silica particles, such as Resiflow™ P-67, available from Estron Chemical, Inc. of Calvert City, Kentucky, and Modaflow® Powder 6000, available from Allnex USA Inc. of Alpharetta, Georgia. The rheology modifier loading may be up to about 0.5 wt%. Examples of suitable rheology modifiers include bentonite clays and talc.

[0030] A method of preparing a powder coating composition in accordance with the invention includes combining a thermosetting resin system with a catalyst and a thermoplastic. As noted above, the thermosetting resin system can be an existing powder coating or the thermosetting resin system can be formulated from scratch. As also described above, it is beneficial to use a thermoplastic that has hydrogen bonding capabilities towards the thermosetting resin system. The resulting powder coating composition can be applied to a properly prepared metallic substrate and subsequently cured. As used herein, the term “properly prepared” refers to a substrate surface that is clean, dry, and free of oil, dirt, and other contaminates. The substrate can either be preheated up to 150°C or coated at room temperature or at any temperature in between. Once the powder coating composition has been applied to the substrate and cured, the resulting coating suitably has a film thickness between about 3 and 9 mils, or between about 5 and 7 mils, with no indication of holidays on edges of the substrate, as evidenceof sufficient edge coverage. This film thickness is lower than conventional coatings applied to laser-cut edges. In particular, it is surprising to be able to achieve edge coverage of sharp edges that are also smooth and high gloss at such low film thickness.

[0031] The powder coating composition has optimized viscosity and cure profiles, resulting in good leveling. More particularly, the resulting powder coating composition has a melt viscosity profile high enough to prevent edge dewetting, but low enough to allow proper leveling. For example, the melt viscosity may be between 30 and 100 mm plate flow, or between 40 and 70 mm plate flow with a 0.8 gram pellet. Additionally, the resulting powder coating composition also has a cure rate fast enough to vitrify prior to dewetting, but slow enough to allow proper leveling. For example, the cure rate may be between 10 and 30 minutes at 375°F, or between 12 and 20 minutes at 375°F.

[0032] The powder coating composition can be applied to a variety of substrates, including metallic substrates, namely, steel and aluminum alloys. The powder coating composition is particularly useful for providing edge coverage on sharp metal edges of laser-cut materials, as evidenced by ASTM D5162-21 Test Method A at a specified minimum coating thickness, which shows that the coating, when applied and cured on a properly prepared metallic substrate, shows no indication of holidays on edges of the substrate. These beneficial results can be achieved without requiring the extra time and expense of applying a pretreatment to the edge of the substrate.

[0033] The powder coating composition can be applied to a substrate in the same manner as conventional powder coatings are applied to substrates. For example, an electrostatic spray gun can be used for applying the powder coating composition to a substrate. For optimal performance, the electrostatic spray gun settings can be 20-100 kV. In addition to improving powder coating application, electrostatic spray guns can reduce back ionization. Compared to conventional powder coatings, the powder coating compositions described herein can more easily build film thickness on laser-cut edges. Not only do the compositions provide edge coverage, but the coverage is smooth and with high gloss as well. Furthermore, the compositions minimize changes to weathering and corrosion performance. Yet another benefit of the compositions is that the powdercoating compositions herein are solvent and heat resistant, with these qualities being attributable to the inclusion of the thermosetting resin.

[0034] Surface smoothness can be measured using PCI Standards. Smoothness values achieved by the powder coating composition can range from 1 to 10, or from 4 to 7. Similarly, the gloss of the coatings can be measured using ASTM D523. 60° Gloss values achieved by the powder coating composition can range from 1 to 100, or from 85 to 95. While the powder coating composition beneficially provides high gloss finished products, the powder coating composition can also enhance the gloss of lower gloss materials as well.EXAMPLES

[0035] These examples show the superior edge coverage as well as corrosion resistance of a panel treated with a powder coating composition according to the invention compared to a panel treated with a conventional powder coating.

[0036] Corrosion Resistance

[0037] To compare the corrosion resistance of the powder coating composition of the invention with a conventional powder coating, each testing panel was either a 10.16 cm x 15.24 cm sheet of laser cut steel having a thickness of 6.3 mm or a 10.16 cm x 20.32 cm sheet of laser cut steel having a thickness of 3.18 mm with a 5.08 cm x 7.62 cm window cut out with a laser. In the first experiment the first powder coating (Formula #1 ) was a traditional polyester-TGIC high-gloss white powder coating. A second powder coating (Formula #2) included the same traditional polyester-TGIC high-gloss white powder coating modified with 5% Platamid H 1937, a copolyimide thermoplastic hot melt adhesive available from Arkema Inc. of King of Prussia, Pennsylvania. Each powder coating was electrostatically sprayed onto the respective panel at various thicknesses ranging from 3 to 9 mils and cured for 15 minutes at 375°F. After fully curing, the coated panels were placed in a salt spray cabinet for 504 hours in accordance with ASTM B117 Salt Spray testing to test the corrosion resistance of the coated panels. As shown in FIG. 1 , the addition of the polymer additive leads to the enhancement of edge protection onthe laser cut steel, with less corrosion at identical film thicknesses for polyester-TGIC powder coatings.

[0038] Formula #1 , the white superdurable polyester-TGIC control sample, is shown in FIG. 1 after the corrosion testing.

[0039] Formula #2, with the modified white superdurable polyester-TGIC powder coating, is shown in FIG. 1 after the corrosion testing. Visually comparing the two samples, Formula #2 with the modified powder coating clearly has much less corrosion than Formula #1 .

[0040] Table 1 : Compositions of the samples shown in FIG. 1

[0041] To compare performance when a coating uses organic pigments, a second experiment was conducted. In the second experiment, the first powder coating (Formula #3) was a traditional polyester-TGIC high-gloss red powder coating. A second powder coating (Formula #4) included the same traditional polyester-TGIC high-gloss red powder coating modified with 7% Platamid H 1937, a copolyimide thermoplastic hot melt adhesive available from Arkema Inc. of King of Prussia, Pennsylvania. Each powder coating was electrostatically sprayed onto the respective panels at various thicknesses ranging from 3 to 12 mils and cured for 15 minutes at 400°F. After fully curing, the coated panels were placed in a salt spray cabinet for 504 hours in accordance with ASTM B117 to test the corrosion resistance of the coated panels. As shown in FIG. 2, the addition of the polymer additive leads to the enhancement of edge protection on the laser cut steel, with less corrosion at identical film thicknesses for super durable polyester-TGIC powder coatings at lower pigment levels.

[0042] Table 2: Compositions of the samples shown in FIG. 2

[0043] Formula #3, the red superdurable polyester-TGIC control sample, is shown in FIG. 2 after the corrosion testing.

[0044] Formula #4, with the modified red superdurable polyester-TGIC powder coating, is shown in FIG. 2 after the corrosion testing. Visually comparing the two samples, Formula #4 with the modified powder coating clearly has much less corrosion than Formula #3.

[0045] To compare the performance when a secondary isocyanate crosslinker is added to the coating formulation, a third experiment was conducted. In the third experiment, the first powder coating (Formula #5) was a superdurable polyester high- gloss red powder coating crosslinked with both TGIC and a blocked isocyanate (Crelan® Nl 2 available from Covestro AG in Germany), hereby known as an ultradurable powder coating. A second powder coating (Formula #6) included the same ultradurable red powder coating modified with 7% Platamid H 1937, a copolyimide thermoplastic hot melt adhesive available from Arkema Inc. of King of Prussia, Pennsylvania. Each powder coating was electrostatically sprayed onto the respective panels at various thicknesses ranging from 4 to 12 mils and cured for 15 minutes at 400°F. After fully curing, the coated panels were placed in a salt spray cabinet for 504 hours in accordance with ASTM B117 to test the corrosion resistance of the coated panels. As shown in FIG. 3, the addition of the polymer additive leads to the enhancement of edge protection on the laser cut steel, with less corrosion at identical film thicknesses for polyester-TGIC-isocyanate (ultradurable) powder coatings.

[0046] Table 3: Compositions of the samples shown in FIG. 3

[0047] Formula #5, the red ultradurable control coating, is shown in FIG. 3 after the corrosion testing.

[0048] Formula #6, with the modified red ultradurable powder coating, is shown in FIG. 3 after the corrosion testing. Visually comparing the two samples, Formula #6 with the modified ultradurable powder coating clearly has much less corrosion than Formula #5.

[0049] To compare the performance when TGIC is replaced with a hydroxyalkylamide crosslinker, a fourth experiment was conducted. In the fourth experiment, the first powder coating (Formula #7) was a superdurable polyester high- gloss white powder coating crosslinked with a hydroxyalkylamide (HAA) crosslinker (React PCH 201 available from KSCNT Co., Ltd, in South Korea). A second powder coating (Formula #8) included the same superdurable polyester-HAA white powder coating modified with 4% Platamid H 1937, a copolyimide thermoplastic hot melt adhesive available from Arkema Inc. of King of Prussia, Pennsylvania. Each powder coating was electrostatically sprayed onto the respective panels at various thicknesses ranging from 5 to 10 mils and cured for 15 minutes at 400°F. After fully curing, the coated panels were placed in a salt spray cabinet for 312 hours in accordance with ASTM B117 to test the corrosion resistance of the coated panels. As shown in FIG. 4, the addition of the polymer additive leads to the enhancement of edge protection on the laser cut steel, with less corrosion at identical film thicknesses for superdurable polyester-hydroxyalkylamide powder coatings.

[0050] Table 4: Compositions of the samples shown in FIG. 4

[0051] Formula #7, the white superdurable polyester-HAA control coating, is shown in FIG. 4 after the corrosion testing.

[0052] Formula #8, with the modified white superdurable polyester-HAA powder coating, is shown in FIG. 4 after the corrosion testing. Visually comparing the two samples, Formula #8 with the modified superdurable polyester-HAA powder coating clearly has much less corrosion than Formula #7.

[0053] Edge Coverage

[0054] To compare the edge coverage of the powder coating composition of the invention with a conventional powder coating, each testing panel was a 10.16 cm x 15.24 cm sheet of steel having a thickness of 6.3 mm. A first powder coating (same as Formula #1 above) was a traditional polyester-TGIC high-gloss white powder coating. A second powder coating (same as Formula #2 above) included the same traditional polyester- TGIC high-gloss white powder coating modified with 5% Platamid H 1937, a copolyimide thermoplastic hot melt adhesive available from Arkema Inc. of King of Prussia, Pennsylvania. Each powder coating was electrostatically sprayed onto the respective panel at a thickness of 4-6 mils and cured for 15 minutes at 375°F. After fully curing, the coated panels were laser cut and the cut edges were then polished and embedded into epoxy resin to maintain stability.

[0055] FIG. 5 shows the laser-cut edge of the steel panel coated with Formula #1 , the control sample. As shown in FIG. 5, the edge of the steel is not fully protected. The sample was obtained by cutting a coated laser cut steel panel and then polishing and embedding it into epoxy resin to keep it stable.

[0056] FIG. 6 shows the laser-cut edge of the steel panel coated with Formula #2, with the modified powder coating. Visually comparing the two samples, it is clear that thelaser-cut edge of the steel with Formula #1 is not fully protected. In contrast, the lasercut edge of the steel with Formula #2 is fully covered by an over 25 micron thick layer of powder coating. The sample was obtained by cutting a coated laser cut steel panel and then polishing and embedding it into epoxy resin to keep it stable.

[0057] FIG. 7 is a particle size distribution curve of three different powder coatings. The first coating, P91635YSC is a superdurable polyester-TGIC powder coating enhanced with Platamid 1937, the second coating (P91626KSC) is a superdurable polyester-TGIC powder coating enhanced with Platamid 1937, and the third coating (P91494WSC) is a superdurable polyester-TGIC powder coating without the Platamid 1937. The distribution curves show a tighter particle size distribution indicating the final powder is more monodisperse. There is a decrease in the super fine particles (< 10 microns) along with a narrowing of the top end particle size. This tighter particle size distribution generates a more consistent applicable powder to enhance the edge build when it is cured. The reduced amounts of small particles (< 10 micron) allow the modified coating to penetrate Faraday areas better along with reducing the likelihood of back ionization occurring during application. A summary of the three coating samples is provided in Table 5 below:

[0058] Table 5: Coating samples corresponding to the particle distribution curve in FIG. 7.

[0059] The descriptions and figures included herein depict specific implementations to teach those skilled in the art how to make and use the best option. For the purpose of teaching inventive principles, some conventional aspects have been simplified or omitted. Those skilled in the art will appreciate variations from these implementations that fall within the scope of the invention. Those skilled in the art will also appreciate that the features described above can be combined in various ways to form multipleimplementations. As a result, the invention is not limited to the specific implementations described above, but only by the claims and their equivalents.

Claims

CLAIMS1 . A powder coating composition, comprising: a thermosetting resin system; a catalyst; and between 1 and 15 pphr thermoplastic, wherein the thermoplastic has hydrogen bonding capabilities towards the thermosetting resin system.

2. The powder coating composition according to claim 1 , wherein the thermosetting resin system comprises at least one of the group consisting of: a carboxyl functional polyester crosslinked with TGIC, a carboxyl functional polyester crosslinked with epoxide functional DGEBA style resin, a carboxyl functional polyester crosslinked with hydroxyl alkyl amide, a hydroxyl functional polyester crosslinked with a multifunctional isocyanate, a carboxyl functional polyester crosslinked with an epoxide functional acrylic resin, and a carboxyl functional acrylic resin crosslinked with an epoxide functional DGEBA style resin.

3. The powder coating composition according to claim 1 , wherein the thermosetting resin system comprises a carboxyl functional polyester with acid value between 25 and 70 with a stoichiometric ratio for carboxykepoxide between 0.9 and 1 .2 using TGIC as a crosslinking agent.

4. The powder coating composition according to claim 1 , wherein the catalyst is present in a concentration that achieves a gel time between 5 and 90 seconds at 200°C for a final product of the powder coating.

5. The powder coating composition according to claim 1 , wherein the thermoplastic is a polyamide or a polyester or a combination of a polyamide and a polyester.

6. The powder coating composition according to claim 1 , wherein the thermoplastic has a viscosity of at least 5000 mPa*s at 200°C.

7. The powder coating composition according to claim 1 , wherein the thermoplastic has a Tg less than 60°C and a melting point between 70 and 130°C.

8. The powder coating composition according to claim 1 , wherein the thermoplastic has intrinsic anti-static properties.

9. The powder coating composition according to claim 1 , wherein the thermoplastic has a chemical composition that allows compatibility with the thermosetting resin system.

10. The powder coating composition according to claim 9, wherein the thermoplastic is compatible enough with the thermosetting resin system to allow greater than 85 60° gloss in an absence of matting agents.11 . The powder coating composition according to claim 1 , further comprising at least one of the group consisting of: a pigment, a filler, a degassing agent, a flow additive, a leveling additive, and a rheology modifier.

12. The powder coating composition according to claim 11 , wherein the pigment loading is between 1 and 30 wt%.

13. The powder coating composition according to claim 11 , wherein the filler loading is between 0 and 50 wt%.

14. The powder coating composition according to claim 11 , wherein the degassing agent is a benzoin degassing agent at a level between 0.5 and 1 .2 wt%.

15. The powder coating composition according to claim 11 , wherein the flow additive and the leveling additive loading is between 0.5 and 1 .5 wt%.

16. The powder coating composition according to claim 11 , wherein the rheology modifier loading is up to 0.5 wt%.

17. The powder coating composition according to claim 1 , wherein the coating composition, when applied and cured on a properly prepared metallic substrate, shows no indication of holidays on edges of the metallic substrate in accordance with ASTM D5162-21 Test Method A at a specified minimum coating thickness.

18. A method of preparing a powder coating composition, comprising: combining a thermosetting resin system with a catalyst and between 1 and 15 pphr thermoplastic, wherein the thermoplastic has hydrogen bonding capabilities towards the thermosetting resin system.

19. The method according to claim 18, wherein the thermosetting resin system comprises at least one of the group consisting of: a carboxyl functional polyester crosslinked with TGIC, a carboxyl functional polyester crosslinked with epoxide functional DGEBA style resin, a carboxyl functional polyester crosslinked with hydroxyl alkyl amide, a hydroxyl functional polyester crosslinked with a multifunctional isocyanate, a carboxyl functional polyester crosslinked with an epoxide functional acrylic resin, and a carboxyl functional acrylic resin crosslinked with an epoxide functional DGEBA style resin.

20. The method according to claim 18, wherein the catalyst is present in a concentration that achieves a gel time between 5 and 90 seconds at 200°C for a final product of the powder coating.

21. The method according to claim 18, wherein the thermoplastic is a polyamide or a polyester or a combination of a polyamide and a polyester.

22. The method according to claim 18, wherein the thermoplastic has intrinsic antistatic properties.

23. The method according to claim 18, further comprising adding at least one of the group consisting of: a pigment, a filler, a degassing agent, a flow additive, a leveling additive, and a rheology modifier, to the powder coating composition.

24. The method according to claim 18, further comprising applying the coating composition on a properly prepared metallic substrate and curing the coating composition after application, wherein the cured coating composition shows no indication of holidays on edges of the metallic substrate in accordance with ASTM D5162-21 Test Method A at a specified minimum coating thickness.

25. The method according to claim 18, wherein the thermosetting resin system is an existing powder coating composition.

26. A method of applying a powder coating composition to a metallic substrate, comprising: forming a powder coating composition by combining a thermosetting resin system with a catalyst and between 1 and 15 pphr thermoplastic, wherein the thermoplastic has hydrogen bonding capabilities towards the thermosetting resin system; applying the powder coating composition to a properly prepared metallic substrate; and curing the powder coating composition on the metallic substrate, wherein the powder coating composition shows no indication of holidays on edges of the metallic substrate in accordance with ASTM D5162-21 Test Method A at a specified minimum coating thickness.

27. The method according to claim 26, wherein the thermosetting resin system comprises at least one of the group consisting of: a carboxyl functional polyester crosslinked with TGIC, a carboxyl functional polyester crosslinked with epoxide functional DGEBA style resin, a carboxyl functional polyester crosslinked with hydroxylalkyl amide, a hydroxyl functional polyester crosslinked with a multifunctional isocyanate, a carboxyl functional polyester crosslinked with an epoxide functional acrylic resin, and a carboxyl functional acrylic resin crosslinked with an epoxide functional DGEBA style resin.

28. The method according to claim 26, wherein, when forming the powder coating composition, adding at least one of the group consisting of: a pigment, a filler, a degassing agent, a flow additive, a leveling additive, and a rheology modifier.

29. The method according to claim 26, wherein the catalyst is present in a concentration that achieves a gel time between 5 and 90 seconds at 200°C for a final product of the powder coating.

30. The method according to claim 26, wherein the thermoplastic is a polyamide or a polyester or a combination of a polyamide and a polyester.31 . The method according to claim 26, wherein the thermoplastic has intrinsic antistatic properties.

32. The method according to claim 26, wherein the thermosetting resin system is an existing powder coating composition.

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