Silicone hydrogel lenses with water-rich surfaces
The invention is related to a hydrated silicone hydrogel contact lens having a layered structural configuration: a lower water content silicone hydrogel core (or bulk material) completely covered with a layer of a higher water content hydrogel totally or substantially free of silicone. A hydrated silicone hydrogel contact lens of the invention possesses high oxygen permeability for maintaining the corneal health and a soft, water-rich, lubricious surface for wearing comfort.
1. A hydrated silicone hydrogel contact lens, comprising:
a silicone hydrogel material comprising repeating units of a polysiloxane-containing vinylic monomer and repeating units of a hydrophilic vinylic monomer; and
an opposite posterior surface,
wherein the hydrated silicone hydrogel contact lens has an oxygen transmissibility of at least about 40 barrers/mm, a water content of from about 10% to about 75% by weight, an elastic modulus of from about 0.3 MPa to about 1.8 MPa, a surface wettability characterized by having an averaged water contact angle of about 80 degrees or less, and a surface hydrophilicity characterized by having a WBUT of at least about 10 seconds,
wherein the hydrated silicone hydrogel contact lens has a cross-sectional surface-modulus profile which comprises, along a shortest line between the anterior and posterior surfaces on the surface of a cross section of the hydrated silicone hydrogel contact lens, an anterior outer zone including and near the anterior surface, an inner zone including and around the center of the shortest line, and a posterior outer zone including and near the posterior surface, wherein the anterior outer zone has an average anterior surface modulus (designated as SM Ant ) while the posterior outer zone has an average posterior surface modulus (designated as SM Post ), wherein the inner zone has an average inner surface modulus (designated as SM Inner ), wherein at least one of
SM
Inner
_
-
SM
Post
_
SM
Inner
_
×
100
%
and
SM
Inner
_
-
SM
Ant
_
SM
Inner
_
×
100
%
is at least about 20%, wherein the anterior and posterior outer zones covers a span of at least about 0.1 μm.
2. The hydrated silicone hydrogel contact lens of claim 1 , wherein the anterior and posterior outer zones covers a span of from about 0.25 μm to about 15 μm.
3. The hydrated silicone hydrogel contact lens of claim 1 , wherein the anterior and posterior outer zones covers a span of from about 0.5 μm to about 12.5 μm.
4. The hydrated silicone hydrogel contact lens of claim 1 , wherein the anterior and posterior outer zones covers a span of from about 1 μm to about 10 μm.
5. The hydrated silicone hydrogel contact lens of claim 1 , wherein the hydrated silicone hydrogel contact lens has an oxygen transmissibility of at least about 60 barrers/mm.
6. The hydrated silicone hydrogel contact lens of claim 5 , wherein the hydrated silicone hydrogel contact lens has a surface wettability characterized by having an averaged water contact angle of about 70 degrees or less.
7. The hydrated silicone hydrogel contact lens of claim 5 , wherein the hydrated silicone hydrogel contact lens has a surface wettability characterized by having an averaged water contact angle of about 60 degrees or less.
8. The hydrated silicone hydrogel contact lens of claim 5 , wherein the hydrated silicone hydrogel contact lens has a surface wettability characterized by having an averaged water contact angle of about 50 degrees or less.
9. The hydrated silicone hydrogel contact lens of claim 2 , wherein the hydrated silicone hydrogel contact lens has an oxygen transmissibility of at least about 60 barrers/mm.
10. The hydrated silicone hydrogel contact lens of claim 9 , wherein the hydrated silicone hydrogel contact lens has a surface wettability characterized by having an averaged water contact angle of about 70 degrees or less.
11. The hydrated silicone hydrogel contact lens of claim 9 , wherein the hydrated silicone hydrogel contact lens has a surface wettability characterized by having an averaged water contact angle of about 60 degrees or less.
12. The hydrated silicone hydrogel contact lens of claim 9 , wherein the hydrated silicone hydrogel contact lens has a surface wettability characterized by having an averaged water contact angle of about 50 degrees or less.
13. The hydrated silicone hydrogel contact lens of claim 3 , wherein the hydrated silicone hydrogel contact lens has an oxygen transmissibility of at least about 60 barrers/mm.
14. The hydrated silicone hydrogel contact lens of claim 13 , wherein the hydrated silicone hydrogel contact lens has a surface wettability characterized by having an averaged water contact angle of about 70 degrees or less.
15. The hydrated silicone hydrogel contact lens of claim 13 , wherein the hydrated silicone hydrogel contact lens has a surface wettability characterized by having an averaged water contact angle of about 60 degrees or less.
16. The hydrated silicone hydrogel contact lens of claim 13 , wherein the hydrated silicone hydrogel contact lens has a surface wettability characterized by having an averaged water contact angle of about 50 degrees or less.
17. The hydrated silicone hydrogel contact lens of claim 4 , wherein the hydrated silicone hydrogel contact lens has an oxygen transmissibility of at least about 60 barrers/mm.
18. The hydrated silicone hydrogel contact lens of claim 17 , wherein the hydrated silicone hydrogel contact lens has a surface wettability characterized by having an averaged water contact angle of about 70 degrees or less.
19. The hydrated silicone hydrogel contact lens of claim 17 , wherein the hydrated silicone hydrogel contact lens has a surface wettability characterized by having an averaged water contact angle of about 60 degrees or less.
20. The hydrated silicone hydrogel contact lens of claim 17 , wherein the hydrated silicone hydrogel contact lens has a surface wettability characterized by having an averaged water contact angle of about 50 degrees or less.
21. The hydrated silicone hydrogel contact lens of claim 1 , wherein at least one of
SM
Inner
_
-
SM
Post
_
SM
Inner
_
×
100
%
and
SM
Inner
_
-
SM
Ant
_
SM
Inner
_
×
100
%
is at least about 25%.
22. The hydrated silicone hydrogel contact lens of claim 1 , wherein at least one of
SM
Inner
_
-
SM
Post
_
SM
Inner
_
×
100
%
and
SM
Inner
_
-
SM
Ant
_
SM
Inner
_
×
100
%
is at least about 30%.
23. The hydrated silicone hydrogel contact lens of claim 1 , wherein at least one of
SM
Inner
_
-
SM
Post
_
SM
Inner
_
×
100
%
and
SM
Inner
_
-
SM
Ant
_
SM
Inner
_
×
100
%
is at least about 35%.
24. The hydrated silicone hydrogel contact lens of claim 1 , wherein at least one of
SM
Inner
_
-
SM
Post
_
SM
Inner
_
×
100
%
and
SM
Inner
_
-
SM
Ant
_
SM
Inner
_
×
100
%
is at least about 40%.