| 摘要 |
A method of manufacturing powder coating compositions, the powder coating compositions, and cured coatings made from the coating compositions are described. The method of preparing the coating compositions comprises combining a preformulated thermally softenable resin powder (having a defined Tg) and a reflective pigments (such as a non-leafing or leafing metallic flake, mica, optically variable pigment, and the like) and then mixing the powder and flake under high shear conditions and assuring that the average temperature of the mixture remains below the Tg of the resin during the high speed mixing process. The powder coating compositions are free of pasted aluminum flake and comprise thermally softenable resin particles having a number average diameter of between 15 and 60 microns, leafed metallic flakes having a number average maximum diameter of between 4 and 45 microns, said powder when coated onto a metallic surface in a thickness of at least 10 microns and melted and cured, providing a reflectivity of at least 400 at 20 degrees viewing angle. The resultant coating may also be free of the plasticizer, solvent or thickener used in pasted aluminum.
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