Dust≤100 ppm High Clarity PET Resin Chip for PET Sheet Material Production Problem PET sheet and thermoforming lines are highly sensitive to fines and dust, which clog feeders, cause gel spots and create surface defects. Black specks and gels force downgrades, and the sheet may fail transparency requirements for food trays. Sheet lines run at controlled thickness, so even a tiny gel or speck is magnified across a large surface and can downgrade a whole roll. Black specks and