Contamination-resistant coated substrates
View Patent ↗A coated substrate is claimed. The coating, disposed on the substrate, comprises a self-assembled film having at least one bilayer. Each bilayer comprises a polyanion electrolyte layer and a polycation electrolyte layer. The uppermost layer or exposed layer of the coating comprises a fluoroalkyl group. Each bilayer thickness ranges from about 0.1 nanometers to about 20 nanometers. The resulting coated substrate has a low surface energy and is hydrophobic and/or oleophobic.
1. A coated substrate comprising:
a substrate;
a coating disposed on the substrate, wherein the coating comprises a self-assembled film having at least one bilayer, wherein each bilayer comprises a polyanion electrolyte layer and a polycation electrolyte layer, wherein an uppermost layer is a compound comprising a fluoroalkyl group; and
wherein each bilayer thickness ranges from about 0.1 nanometers to about 20 nanometers and wherein the coating absorbs less than 1% of transmitted light between wavelengths of about 300 nanometers to about 3000 nanometers.
2. A coated substrate according to claim 1 , wherein the substrate is an inorganic substrate selected from the group consisting of: silica glass, quartz glass, sapphire, ruby, spinel ceramic glass, yttrium silver, optical high-lead glass, cubic zirconia, a reflecting material, and a high index optical quality glass.
3. A coated susbstrate according to claim 1 , wherein the substrate is silica glass.
4. A coated substrate according to claim 1 , wherein the substrate is an organic substrate selected from the group consisting of: polyester, polycarbonate, polyacrylate, poly(methyl methacrylate), polyamide, and polystyrene.
5. A coated substrate according to claim 4 , wherein the substrate is polycarbonate.
6. A coated substrate according to claim 4 , wherein the substrate is polyester.
7. A coated substrate according to claim 4 , wherein the substrate is polyacrylate.
8. A coated substrate according to claim 1 , wherein the substrate is an optical substrate.
9. A coated substrate according to claim 8 , wherein the optical substrate is either transparent or reflecting.
10. A coated substrate according to claim 9 , wherein the optical substrate is transparent.
11. A coated substrate according to claim 1 , wherein the substrate has a shape selected from the group consisting of: curved, flat cylindrical, conical, and spherical.
12. A coated substrate according to claim 11 , wherein the substrate has a curved shape.
13. A coated substrate according to claim 11 , wherein the substrate has a flat shape.
14. A coated substrate according to claim 1 , wherein the polyanion electrolyte comprises a poly(acrylic acid) polyelectrolyte.
15. A coated substrate according to claim 14 , wherein the poly(acrylic acid) polyelectrolyte has the structure:
where: y=1 to 200,000;
M is selected from the group consisting of: H, Li, Na and K; and
R is selected from the group consisting of: hydrogen, methyl or ethyl.
16. A coated substrate according to claim 14 , wherein the poly(acrylic acid) polyelectrolyte is a fluorocarbon-modified poly(acrylic acid) having the structure:
where:
y=0.1 to 90 mole percent;
M is selected from the group consisting of: H, Li, Na, and K;
R 1 is selected from the group consisting of: H, CH 3 , and CH 3 CH 2 —;
R 2 is selected from the group consisting of: H, CH 3 , and CH 3 CH 2 —;
R 3 is selected from the group consisting of: —(CH 2 CH 2 —O) x where x=1 to 20;
R 4 is selected from the group consisting of: —(CF 2 ) n CF 3 where n=1 to 50.
17. A coated substrate according to claim 1 , wherein the polycation electrolyte comprises a poly(allylamine hydrochloride) polycation.
18. A coated substrate according to claim 17 , wherein the poly(allylamine hydrochloride) polycation has the structure:
where x=1 to 200,000.
19. A coated substrate according to claim 1 , wherein the fluoroalkyl group has the structure:
where x=0to 50.
20. A coated substrate according to claim 1 , wherein the polycation is a fluorinated polycation.
21. A coated substrate according to claim 1 , wherein the polyanion is a fluorinated polyanion.
22. A coated substrate according to claim 1 , wherein the coating comprises a plurality of bilayers and the coating has a thickness of about 0.1 nanometers to about 200 nanometers.
23. A coated substrate according to claim 22 , wherein the coating has a thickness of about 1 nanometer to about 10 nanometers.
24. A coated substrate prepared by:
a) providing a substrate;
b) applying a first electrolyte layer to the substrate;
c) applying a second electrolyte later to the first electrolyte layer and allowing the second electrolyte layer to react with the first electrolyte layer to form a bilayer;
d) applying a compound comprising a fluoroalkyl group to the bilayer to form a coating on the substrate, wherein the coating absorbs less than 1% of transmitted light between lengths of about 300 nanometers to about 3000 nanometers.
25. A coated substrate according to claim 24 , wherein the steps of applying a second electrolyte layer to the first electrolyte layer are repeated a plurality of times to form a coating having a thickness ranging from about 0.1 nanometers to about 200 nanometers.
26. A coated substrate according to claim 24 , wherein the first electrolyte layer is a polyanion electrolyte layer and wherein the second electrolyte layer is a polycation electrolyte layer.
27. A coated substrate according to claim 24 , wherein the first electrolyte layer is a polycation electrolyte layer and the second electrolyte layer is a polyanion electrolyte layer.
28. A coated substrate according to claim 26 , wherein the polyanion electrolyte layer comprises a poly(acrylic acid) polyelectrolyte.
29. A coated substrate according to claim 28 , wherein the poly(acrylic acid) polyelectrolyte has the structure:
where: y=1 to 200,000;
M is selected from the group consisting of: H, Li, Na and K; and
R is selected from the group consisting of: H, CH 3 -, and CH 3 CH 2 -.
30. A coated substrate according to claim 28 , wherein the poly(acrylic acid) polyelectrolyte is a fluorocarbon-modified poly(acrylic acid) having the structure:
where:
y=0.1 to 90 mole percent;
M is selected from the group consisting of: H, Li, Na, and K;
R 1 is selected from the group consisting of: H, CH 3 , and CH 3 CH 2 —;
R 2 is selected from the group consisting of: H, CH 3 , and CH 3 CH 2 —;
R 3 is selected from the group consisting of: —(CH 2 CH 2 —O) x where x=1 to 20;
R 4 is selected from the group consisting of: —(CF 2 ) n CF 3 where n=1 to 50.
31. A coated substrate according to claim 26 , wherein the poly(allylamine hydrochloride) polycation has the structure:
where x=1 to 200,000.
32. A coated substrate according to claim 27 , wherein the poly(allylamine hydrochloride) polycation has the structure:
where x=1 to 200,000.
33. A coated substrate according to claim 27 , wherein the polyanion electrolyte layer comprises a poly(acrylic acid) polyelectrolyte.
34. A coated substrate according to claim 33 , wherein the poly(acrylic acid) polyelectrolyte has the structure:
where: y=1 to 200,000;
M is selected from the group consisting of: H, Li, Na and K; and
R is selected from the group consisting of: H, CH 3 -, and CH 3 CH 2 -.
35. A coated substrate according to claim 33 , wherein the poly(acrylic acid) polyelectrolyte is a fluorocarbon-modified poly(acrylic acid) having the structure:
where:
y=0.1 to 90 mole percent;
M is selected from the group consisting of: H, Li, Na, and K;
R 1 is selected from the group consisting of: H, CH 3 , and CH 3 CH 2 —;
R 2 is selected from the group consisting of: H, CH 3 , and CH 3 CH 2 —;
R 3 is selected from the group consisting of: —(CH 2 CH 2 —O) x where x=1 to 20;
R 4 is selected from the group consisting of: —(CF 2 ) n CF 3 where n=1 to 50.
36. A coated substrate according to claim 24 , wherein the fluoroalkyl group has the structure:
where x=0 to 50.
37. A coated substrate according to claim 26 , wherein the polyanion electrolyte layer comprises a fluorinated polyanion.
38. A coated substrate according to claim 26 , wherein the polycation electrolyte layer comprises a fluorinated polycation.
39. A coated substrate according to claim 38 , wherein the polyanion electrolyte layer comprises a fluorinated polyanion.
40. A coated substrate according to claim 24 , wherein the polyanion electrolyte layer comprises a fluorinated polyanion.
41. A coated substrate according to claim 24 , wherein the polycation electrolyte layer comprises a fluorinated polycation.
42. A coated substrate according to claim 41 , wherein the polyanion electrolyte layer comprises a fluorinated polyanion.