| 摘要 |
PROBLEM TO BE SOLVED: To sufficiently maintain the mechanical strength and weatherability of a coating film and to obtain a matte coating surface having good reproducibility by deposition a powder coating material consisting essentially of a polyester resin on a material to be coated to form a first coating film layer, laminating a second coating film layer consisting essentially of an acrylic resin thereon before baking and baking these coating film layers. SOLUTION: The powder coating material for the first coating film layer is obtd. by incorporating a binder resin essentially consisting of the polyester resin, a hardener and other additives therein, subjecting the material to dry process mixing and thermally melting and kneading the mixture, then pulverizing the mixture and classifying the powder until the particle size attains a range of 5 to 50μm in volumetric 50% diameter measured by a Coulter counter. The second coating film layer contains the binder consisting essentially of the acrylic resin, the hardener and the other additives. The coating material for the first coating film is applied on the material to be coated in such a manner that the coating thickness after baking attains 20 to 50μm. The second coating film layer is laminated thereon before the baking of this coating film and thereafter, the coating films are baked for 5 to 30 minutes at 150 to 230 deg.C.
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