Material Drying
1 views
PET sheet haze and poor transparency
Problem Phenomenon
The sheet is hazy and cloudy with reduced gloss; the appearance does not meet transparent packaging requirements
Cause Analysis
Trace amounts of moisture affect PET optical properties; degraded material loses transparency; impurities from poor filtration scatter light; unstable cooling changes crystallization behavior and produces haze
Solution
① Strengthen drying performance; ② upgrade the melt filtration system; ③ optimize cooling and calendering processes to keep roll temperature stable; after adjustment, continuously sample to verify the effect, and resume mass production only after confirming stability
Key Takeaway
PET transparency is the product of multiple factors; any loss of control of the four variables—moisture, degradation, impurities, and crystallization—will cause haze; after confirming effectiveness, fix the parameters and practices into the work instruction to prevent recurrence
Was this helpful?
0 people found this helpful
Thank you for your feedback!