Optical lens comprising a protective removable film
The invention concerns an optical lens comprising (i) a temporary coating at least partially covering a surface of the lens, said temporary coating comprising an outermost layer mechanically degradable through friction and/or contact; (ii) a removable film having opposite first side and second sides which adhere to said outermost layer through its first side, wherein—the first side of the film has a roughness Rq lower than 750 nm and the first side of the film has a surface energy lower than 38 mJ/m 2 .
1. An optical lens comprising
(i) a temporary coating at least partially covering a surface of the lens, said temporary coating comprising an outermost layer mechanically degradable through friction and/or contact;
(ii) a removable film having opposite first side and second sides which adhere to said outermost layer through its first side, wherein
the first side of the film has a roughness Rq lower than 750 nm and
the first side of the film has a surface energy lower than 38 mJ/m 2 .
2. The optical lens of claim 1 , wherein the removable film has a Young's modulus lower than 170 MPa.
3. The optical lens of claim 1 , wherein the removable film has a Young's modulus of lower than or equal to 100 MPa.
4. The optical lens of claim 1 , wherein the surface energy of the first side of the film is lower than or equal to 35 mJ/m 2 .
5. The optical lens of claim 1 , wherein the removable film is made of a polymer chosen from polyolefin, fluorinated polymer, silicone based polymer.
6. The optical lens of claim 5 , wherein the removable film comprises a polydimethyl siloxane (PDMS) polymer.
7. The optical lens of claim 1 , wherein the surface roughness Rq of the removable film is less than or equal to 150 nm.
8. The optical lens of claim 1 , wherein the thickness of the film is ranging from 0.5 microns to 1 mm.
9. The optical lens of claim 1 , wherein the outermost layer of the temporary coating is made of at least one material chosen from metal fluorides, metal oxides, metal hydroxides and mixtures thereof.
10. The optical lens according to claim 9 wherein the metal fluorides are chosen from MgF 2 , LaF 3 , AlF 3 and CeF 3 , the metal oxides are chosen from MgO, CaO, TiO 2 , Al 2 O 3 , ZrO 2 and Pr 2 O 3 , and the metal hydroxides are chosen from Mg(OH) 2 , Ca(OH) 2 and Al(OH) 3 .
11. The optical lens of claim 1 , wherein the temporary coating comprises a layer comprising a metallic fluoride and a layer comprising a material selected from the group of metallic oxides, metallic hydroxides or their mixture deposited over said layer of metallic fluorides.
12. The optical lens of claim 1 , wherein the temporary coating is formed onto a hydrophobic and/or oleophobic coating.
13. The optical lens of claim 12 , wherein the hydrophobic and/or oleophobic coating has a surface energy equal to or lower than 14 mJ/m 2 .
14. The optical lens of claim 12 , wherein the hydrophobic and/or oleophobic coating is obtained by applying successively a first hydrophobic material having a first surface energy and a second hydrophobic material having a second surface energy, wherein the second surface energy is higher than the first surface energy.
15. The optical lens of claim 1 , wherein the removable film contains less than 20wt % of plasticizer.
16. The optical lens of claim 1 , wherein at least 5% the surface of the outermost layer is covered by the removable film.
17. The optical lens of claim 10 , wherein the metal fluoride is MgF 2 .
18. The optical lens of claim 10 , wherein the metal oxide is MgO.