Lens apt to trimming
View Patent ↗A method for treating an ophthalmic lens comprising two main sides, wherein at least one side comprises an organic or mineral external layer coated with a MgF 2 temporary protective layer, said method comprising the specific treating step of depositing the MgF 2 temporary protective layer on the external layer through vacuum evaporation at a speed lower than or equal to 0.5 nm/s. The lens obtained from the above method is capable of being submitted to a trimming operation within 48 hours after the ophthalmic lens has been treated, i.e. after the various layers have been deposited.
1. An ophthalmic lens apt to trimming, comprising a hydrophobic and/or oilophobic coating layer and a MgF 2 temporary protective layer on said hydrophobic and/or oilophobic coating layer, wherein a layer of at least one non-fluorinated metallic oxide and/or at least one non-fluorinated metallic hydroxide is on the MgF 2 protective layer.
2. The ophthalmic lens of claim 1 , wherein the metallic oxide is magnesium oxide, calcium oxide, praseodymium oxide, and/or cerium oxide.
3. The ophthalmic lens of claim 1 , wherein the non-fluorinated metallic hydroxide is magnesium hydroxide.
4. The ophthalmic lens of claim 1 , wherein the hydrophobic and/or oilophobic coating layer has a thickness lower than 30 nm.
5. The ophthalmic lens of claim 4 , wherein the hydrophobic and/or oilophobic coating layer has a thickness ranging from 1 to 20 nm.
6. The ophthalmic lens of claim 4 , wherein the hydrophobic and/or oilophobic coating layer has a thickness ranging from 1 to 10 nm.
7. The ophthalmic lens of claim 1 , wherein the temporary protective layer has a thickness ranging from 5 to 50 nm.
8. The ophthalmic lens of claim 1 , wherein the hydrophobic and/or oilophobic coating layer is on a non-reflecting coating.
9. The ophthalmic lens of claim 8 , wherein the non-reflecting coating is multi-layered.
10. The ophthalmic lens of claim 1 , further comprising an electrostatic film on the non-fluorinated metallic oxide and/or non-fluorinated metallic hydroxide layer.
11. The ophthalmic lens of claim 1 , wherein the metallic oxide is magnesium oxide.