| abstract |
Described herein are methods for producing silicone hydrogel lenses. The methods involve introducing into a mold a water-based lens-forming composition, curing the lens- forming composition in a mold to form the lens, and removing the lens from the mold. The lens-forming composition comprises (i) a polysiloxane-containing vinylic monomer or macromer, (ii) at least one hydrophilic vinylic monomer, (iii) a surfactant, and, and (iv) water. The surfactant is polysiloxane-containing surfactant that is free of actinically- polymerizable groups and is a copolymer having from about 10% to about 40% by weight of one or more polysiloxane segments and from about 90% to about 60% by weight hydrophilic units and/or segments. The methods permit the use of water as a solvent and reduce the need for organic solvents. Additionally, the lenses produced by the methods can have improved properties such oxygen permeability. |