Method for making contact lenses
View Patent ↗The instant invention pertains to a method and a fluid composition for producing contact lenses with improved lens quality and with increased product yield. The method of the invention involves adding a phospholipid into a fluid composition including a lens-forming material in an amount sufficient to reduce an averaged mold separation force by at least about 40% in comparison with that without the phospholipids.
1. A fluid composition for making contact lenses, comprising: a lens-forming material and a PEG-ylated phosphatidyl ethanolamines, wherein the lens-forming material is crosslinkable and/or polymerizable by actinic radiation in a mold to form a contact lens having a polymer matrix, wherein the PEG-ylated phosphatidyl ethanolamines migrates to the interface between the mold and the fluid composition therein to form an intact interfacial film within a desired time period and with a thickness sufficient to reduce averaged mold separation force, wherein the PEG-ylated phosphatidyl ethanolamines is present in an amount sufficient to reduce an averaged mold separation force by at least about 40% in comparison with that without the phospholipids.
2. The fluid composition of claim 1 , where the PEG-ylated phosphatidyl ethanolamines is at least one member selected from the group consisting of PEG-ylated dipalmitoyl phosphatidylethanolamine (DPPE-PEG), PEG-ylated palmitoyloleoyl phosphatidylethanolamine (POPE-PEG), PEG-ylated dioleoyl phosphatidylethanolamine (DOPE-PEG) and PEG-ylated distearoyl phosphatidylethanolamine (DSPE-PEG).
3. The fluid composition of claim 2 , where the PEG-ylated phosphatidyl ethanolamines is PEG-ylated distearoyl phosphatidylethanolamine (DSPE-PEG).
4. The fluid composition of claim 1 , wherein the fluid composition comprises from 0.5% to 10% PEG-ylated phosphatidyl ethanolamines.
5. The fluid composition of claim 4 , wherein the fluid composition comprises from 1.0% to 6.0% PEG-ylated phosphatidyl ethanolamines.
6. The fluid composition of claim 5 , wherein the fluid composition comprises from 1.5% to 4.0% PEG-ylated phosphatidyl ethanolamines.
7. The fluid composition of claim 1 , wherein the lens-forming material comprises at least one prepolymer.
8. The fluid composition of claim 7 , wherein the lens-forming material comprises at least one prepolymer with two or more thiol groups or with two or more ene-containing groups.
9. The fluid composition of claim 7 , wherein the prepolymer is a silicone-containing prepolymer or a silicone-free prepolymer.
10. The fluid composition of claim 7 , wherein the prepolymer is a water-soluble silicone-free prepolymer.
11. The fluid composition of claim 9 , wherein the silicone-containing prepolymer is capable of forming, in the absence of any monomer and/or crosslinking agent, a silicone hydrogel contact lens which has at least one property selected from the group consisting of an apparent oxygen permeability of at least 40 barrers, an Ionoflux Diffusion Coefficient, D, of greater than about 1.5.times.10.sup.−6 mm.sup.2/min, an elastic modulus of from about 0.2 MPa to about 2.0 MPa, and a water content of from about 15% to about 80% by weight when fully hydrated.
12. The fluid composition of claim 1 , wherein the fluid composition comprises at least one components selected from the group consisting of a polymerization initiator, a visibility tinting agent, a UV-blocking (absorbing) agent, a photosensitizer, an antimicrobial agent, a bioactive agent, a mold releasing agent, and a leachable lubricant.