Anti-fog and anti-reflective dual-functional coating for optical articles
A coating for an optical article, such as a lens, includes a bottom coating having at least one hydrophilic resin binder and at least one surfactant, forming an anti-fogging layer, and a top coating overlying the bottom coating, forming an anti-reflective layer. The top coating includes nanopores, which may be less than 150 nm in size.
1. A coating for an optical article, comprising:
a bottom coating comprising at least one hydrophilic resin binder, forming an anti-fogging layer; and
a top coating overlying the bottom coating, forming an anti-reflective layer, the top coating comprising nanopores and nanoparticles.
2. The coating of claim 1 , wherein the nanopores have less than 150 nm pore size.
3. The coating of claim 1 , wherein the top coating further comprises a porosity from about 30% to about 90%.
4. The coating of claim 1 , wherein the nanoparticles have a diameter ranging in size from about 1 to about 150 nm dispersed in a solvent.
5. The coating of claim 1 , wherein the top coating further comprises a transparent, dielectric and non-water-soluble compound selected from the group consisting essentially of oxides, nitrides and sulfides.
6. The coating of claim 1 , wherein the binder is selected from the group consisting essentially of: polyurethane, acrylic, polysiloxane, epoxy, polyvinyl alcohol, polyvinylpyrrolidone, polyethylene glycol, and combinations and hybrids thereof.
7. The coating of claim 1 , wherein the thickness of the top coating is from about 70 to about 200 nm.
8. The coating of claim 1 , wherein the thickness of the bottom coating is from about 2 to about 25 microns.
9. A method of making an optical article, comprising:
providing an optical substrate having a top surface and a bottom surface;
coating the top surface of the optical substrate with a bottom coating comprising at least one hydrophilic resin binder, forming an anti-fogging layer;
coating the bottom coating on the top surface of the optical substrate with a top coating, forming an anti-reflective layer, the top coating comprising nanopores and nanoparticles.
10. The method of claim 9 wherein the nanopores have less than 150 nm pore size.
11. The method of claim 9 , wherein the top coating further comprises a porosity from about 30% to about 90%.
12. The method of claim 9 , wherein the nanoparticles have a diameter ranging in size from about 1 to about 150 nm dispersed in a solvent.
13. The method of claim 9 , wherein the top coating is coated on the optical substrate by a method selected from the group consisting essentially of sol-gel dip-coating, chemical bath deposition, oblique angle evaporation, layer-by-layer assembly, and soft-templated solvent deposition.
14. The method of claim 9 , further comprising:
coating the bottom surface of the optical substrate with the bottom coating; and
coating the bottom coating on the bottom surface of the optical substrate with the top coating.
15. The method of claim 9 , further comprising curing the bottom coating.
16. The method of claim 9 , further comprising curing the top coating.
17. The method of claim 9 , wherein the top coating further comprises a transparent, dielectric and non-water-soluble compound selected from the group consisting essentially of oxides, nitrides and sulfides.
18. An optical article, comprising:
an optical substrate having a top surface and a bottom surface;
a bottom coating overlying the top surface and bottom surface of the optical substrate, comprising at least one hydrophilic resin binder, forming an anti-fogging layer; and
a top coating overlying the bottom coating, forming an anti-reflective layer, the top coating comprising nanopores and nanoparticles.
19. The coating of claim 18 , wherein the nanopores have less than 150 nm pore size.