Patent ID: 8609745

Claim:
A method for producing silicone hydrogel contact lenses, comprising the steps of: (1) obtaining a fluid composition, wherein the composition comprises at least one prepolymer having multiple cinnamic acid moieties of formula (IV) or dialkylmaleimide groups of formula (V) each capable of undergoing photo-induced step-growth polymerization that is 2+2 cycloaddition to form a silicone hydrogel material, in which R 20 is C 1 -C 10 alkene divalent radical, R 21 and R 25 independent each other are hydrogen, C 1 -C 10 alkyl or —NO 2 provided that either R 21 or R 25 is —NO 2 , R 22 -R 24 independent of one another are hydrogen or C 1 -C 10 alkyl; R 26 and R 27 , independent of each other, are C 1 -C 10 alkyl and R 28 is a C 1 -C 10 alkene divalent radical; wherein the prepolymer is obtained from a siloxane-containing copolymer with pendant or terminal functional groups by covalently attaching the cinnamic acid moieties of formula (IV) or dialkylmaleimide groups of formula (V) to the pendant or terminal functional groups of the copolymer; (2) introducing the fluid composition into a cavity formed by a mold, wherein the mold has a first mold half with a first molding surface defining the anterior surface of a contact lens and a second mold half with a second molding surface defining the posterior surface of the contact lens, wherein said first and second mold halves are configured to receive each other such that a cavity is formed between said first and second molding surfaces; and (3) actinically irradiating the composition in the mold to crosslink said at least one prepolymer to form a silicone hydrogel contact lens by 2+2 cycloaddition.