| 摘要 |
PROBLEM TO BE SOLVED: To provide a preparation process of a powder coating for electrostatic coating which yields an excellent shelf stability of a thermosetting powder coating composition and an excellent finished appearance of a coated film. SOLUTION: In the preparation process of a thermosetting powder coating comprising the following steps (1)-(6), the relative humidity of the air contacting the powder coating is adjusted to <=50%. Step (1) grinding step: a step wherein pellets of the thermosetting powder coating are ground into fine powders, step (2) recovery step: a step wherein the ground thermosetting powder coating powders are recovered, step (3) fine powder-removal step: a step wherein fine particles of the thermosetting powder coating are removed, step (4) coarse particle-sieving step: a step wherein the coarse particles of the thermosetting powder coating are removed, step (5) recovery step: a step wherein the classified thermosetting powder coating is recovered, and step (6) storage step: a step wherein the thermosetting powder coating recovered in step (5) is subjected to a final sieving process and canned into a product.
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