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Thread 546/22
PMMA-coated PC failure
March 22, 2010
Some components made of polycarbonate (PC) are coated with PMMA for better UV resistance.
Some of them show the defects in the image: a sort of tree-shaped appearance, visible only form certain points of view (or when the item is wet). Have you ever seen such a kind of defect?
R&D - Carpi, Italy
publicly reply to Andrea Vecchi
The defect is called "crazing". Something has caused it, but I wouldn't know what that would be. You should probably talked to a tech. person at the company that manufacturers your particular brand of polycarbonate if you can. They may have some more advice for you. Good luck.

Jon Barrows, MSF, EHSSC
Independence, Missouri
March 25, 2010
publicly reply to Jon Barrows
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