Multiple layered membrane with thin fluorine containing polymer layer
View Patent ↗A multi-layer membrane includes a fluorine containing layer and a substrate which are joined through spray coating and heat treatment in a multi-step technique.
1. A multi-layer flexible perforated diffuser membrane comprising:
a substrate layer, wherein said substrate layer comprises ethylene propylene diene monomer (EPDM);
a primer layer disposed on said substrate layer; and
a dispersion layer disposed on said primer layer, wherein said dispersion layer comprises polytetrafluoroethylene (PTFE);
wherein said substrate layer, said primer layer and said dispersion layer are perforated to form said multi-layer flexible perforated diffuser membrane.
2. The diffuser membrane of claim 1 , wherein said primer layer is less than 10 microns thick.
3. The diffuser membrane of claim 1 , wherein said diffuser membrane is selected from the group consisting of a tubular shaped membrane, a disc shaped membrane and a panel shaped membrane.
4. The diffuser membrane of claim 1 , wherein said primer layer comprises a material selected from the group consisting of polyamide-imide and polyether sulfone.
5. The diffuser membrane of claim 1 , wherein said dispersion layer is less than 20 microns thick.
6. The diffuser membrane of claim 1 , wherein said dispersion layer is less than 20 microns thick and said dispersion layer is heat treated at a temperature of greater than 120 degrees C. prior to the use of the diffuser membrane.
7. The diffuser membrane of claim 1 , wherein said dispersion layer further comprises a material selected from the group consisting of fluoride acryl resin, xylene, toluene, bentonite, titanium dioxide, carbon black, 2-isocyanatoethyl 2,6-diisocyanatohexanoate, 2,6-diisocyanatohexanoic acid 2-isocyanatoethyl ester and ethyl acetate.
8. The diffuser membrane of claim 1 , wherein said dispersion layer is deposited through a spray.
9. The diffuser membrane of claim 1 , wherein a plasma discharge, a corona discharge, N-methyl pyrrolidone or methyl-ethyl ketone is applied to said substrate layer prior to deposition of said primer layer.