Kentaro,
This ASM Handbook article includes a section on troubleshooting, including discussion of discoloration:
Denis Grimshaw, Powder Coatings-Other Industries, Protective Organic Coatings, Vol 5B, ASM Handbook, Edited By Kenneth B. Tator, ASM International, 2015, p 168–176, https://doi.org/10.31399/asm.hb.v05b.a0006015
Scott
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Scott Henry
Senior Content Engineer
ASM International
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