Process for replacing an initial outermost coating layer of a coated optical lens with a different coating layer or by depositing thereon a different coating layer
View Patent ↗The invention concerns a process for replacing an initial outermost coating layer of a coated optical lens with a layer of a new final coating having surface properties different from those of said initial outermost coating which comprises: (a) providing a coated optical lens having an initial outermost coating layer having a surface contact angle with water of at least 65°; (b) subjecting the initial outermost coating layer to a treatment with activated chemical species at about atmospheric pressure, and for less than one minute, in order there is obtained a treated surface having a contact angle with water of 10° or less; and (c) depositing on said treated surface a layer of a final coating having surface properties different from those of said initial outermost coating.
1. A process comprising:
(a) providing a coated optical lens having an initial outermost coating layer having a surface contact angle with water of at least 65°;
(b) subjecting the initial outermost coating layer to a treatment with activated chemical species at about atmospheric pressure, and for less than one minute, in order there is obtained a treated surface having a contact angle with water of 10° or less ; and
(c) depositing on said treated surface a layer of a final coating having surface properties different from those of said initial outermost coating.
2. The process of claim 1 , wherein the duration of the treatment with activated species (b) is 40s or less.
3. The process of claim 1 , wherein the duration of the treatment with activated species (b) is about 20 s.
4. The process of claim 1 , wherein said treated surface has a contact angle with water of 7° or less.
5. The process of claim 1 , wherein said treated surface has a contact angle with water of 5° or less.
6. The process of claim 1 , wherein the active chemical species are essentially free radicals.
7. The process of claim 6 , wherein said free radicals are oxygen free radicals.
8. The process of claim 1 , wherein the treatment with activated chemical species is a corona discharge treatment.
9. The process of claim 8 , wherein the power of the corona discharge treatment ranges from 10 2 to 2.10 3 W.
10. The process of claim 8 , wherein the power of the corona discharge treatment ranges from 5.10 2 to 10 3 W.
11. The process of claim 1 , wherein the treatment with activated chemical species is a O 2 plasma treatment.
12. The process of claim 1 , wherein said initial outermost coating has a surface energy of at least 15 mJ/m 2 .
13. The process of claim 1 , wherein the final coating has a contact angle with water of at least 100°.
14. The process of claim 1 , wherein the final coating has a surface energy of 25 mJ/m 2 or less.
15. The process of claim 1 , wherein the final coating has a surface energy of 22 mJ/m 2 or less.
16. The process of claim 1 , wherein the final coating has a surface energy of 15 mJ/m 2 or less.
17. The process of claim 1 , wherein the final coating has a surface energy of 12 mJ/m 2 or less.
18. The process of claim 1 , wherein said initial outermost coating layer is a hydrophobic top coat made from a composition comprising at least one fluorinated compound.
19. The process of claim 18 , wherein the fluorinated compound is selected from silanes and silazanes containing at least one fluorocarbon, polyfluorocarbon, fluoropolyether or polyfluoropolyether group.
20. The process of claim 1 , wherein said initial outermost coating layer is deposited on an anti-reflective coating.
21. The process of claim 20 , wherein said anti-reflective coating comprises a stack of alternative low and high refractive index mineral layers.
22. The process of claim 20 , further comprising a scratch-resistant coating.
23. The process of claim 20 , wherein said initial outermost coating layer has a thickness of 1 to 100 nm.
24. The process of claim 20 , wherein said initial outermost coating layer has a thickness of 1 to 5 nm.
25. The process of claim 1 , wherein said final coating has a thickness ranging from 1 to 100 nm.
26. The process of claim 1 , wherein said final coating is deposited by vacuum, dip, spin, spray or stamping coating.
27. The process of claim 1 , wherein said initial outermost coating layer comprises an outer superficial portion of a scratch-resistant coating containing at least one hydrophobic surfactant.
28. The process of claim 27 , wherein the hydrophobic surfactant is a fluorinated compound.
29. The process of claim 28 , wherein the fluorinated compound is a silane or silazane bearing at least one fluorocarbon, polyfluorocarbon, fluoropolyether or polyfluoropolyether group.
30. The process of claim 27 , wherein the outer superficial portion has a thickness of 1 to 100 nm.
31. The process of claim 1 , further comprising air blowing during treatment with activated chemical species to uniformize the action of the reactive chemical species.
32. The process of claim 1 , further comprising the step of edging the lens after steps (a) or (b).
33. The process of claim 1 , further comprising the step of edging the lens after step (a).
34. The process of claim 1 , wherein said optical lens is an ophthalmic lens.
35. The process of claim 1 , wherein the initial outermost coating layer is replaced by the final coating.
36. The process of claim 1 , wherein the final coating is deposited on the initial outermost coating.
37. The process of claim 1 , wherein the duration of the treatment with activated species (b) is 30 seconds or less.
38. The process of claim 20 , wherein said initial outermost coating layer has a thickness of 1 to 60 nm.
39. The process of claim 20 , wherein said initial outermost coating layer has a thickness of 10 to 60 nm.
40. The process of claim 27 , wherein the outer superficial portion has a thickness of 1 to 30 nm.
41. The process of claim 22 , further comprising a primer coating layer.