Why do not use Teflon (polytetrafluoroethylene) instead fluorinated polyurethane?
Teflon has the best performance among all fluorinated polymers. However, it can not form a coating unless a high temperature is applied to melt Teflon to form a continuous film like Teflon on cookware. Fluorinated polyurethane can form a cross-linked coating under ambient temperature. Fluorinated polyurethane has high refractive index and transparency and make coating with brilliant color and high gloss, but Teflon does not such properties.