US 12,391,014 B2
Method for making embedded hydrogel contact lenses
Jing Cheng, Anaheim, CA (US); Michelle Plavnik, Atlanta, GA (US); Ya-Wen Chang, Alpharetta, GA (US); Feng Jing, Snellville, GA (US); and Steve Yun Zhang, Sugar Hill, GA (US)
Assigned to Alcon Inc., Fribourg (CH)
Filed by Alcon Inc., Fribourg (CH)
Filed on May 24, 2023, as Appl. No. 18/322,651.
Claims priority of provisional application 63/365,272, filed on May 25, 2022.
Prior Publication US 2023/0382065 A1, Nov. 30, 2023
Int. Cl. B29D 11/00 (2006.01)
CPC B29D 11/00134 (2013.01) [B29D 11/00442 (2013.01); B29D 11/0048 (2013.01)] 28 Claims
OG exemplary drawing
 
1. A method for producing embedded hydrogel contact lenses, comprising the steps of:
(1) obtaining a female mold half, a first male mold half and a second male mold half, wherein the female mold half has a first molding surface defining the anterior surface of a contact lens to be molded, wherein the first male mold half has a second molding surface defining the back surface of an insert to be molded, wherein the second male mold half has a third molding surface defining the posterior surface of the contact lens to be molded, wherein the first male mold half and the female mold half are configured to receive each other such that an insert-molding cavity is formed between the second molding surface and a central portion of the first molding surface when the female mold half is closed with the first male mold half, wherein the second male mold half and the female mold half are configured to receive each other such that a lens-molding cavity is formed between the first and third molding surfaces when the female mold half is closed with the second male mold half;
(2) dispensing an amount of an insert-forming composition on the central portion of the first molding surface of the female mold half, wherein the insert-forming composition comprises (i) at least one first polymerizable material, (ii) a thermal free-radical initiator, and (iii) a first free-radical photoinitiator that comprises an ethyleneically-unsaturated group and a photoiniator-moiety capable of generating free radicals upon irradiation by an UV and/or visible light;
(3) placing the first male mold half on top of the insert-forming composition in the female mold half and closing the first male mold half and the female mold half to form a first molding assembly comprising the insert-forming composition within the insert-molding cavity;
(4) curing thermally the insert-forming composition in the insert-molding cavity of the first molding assembly to form a molded insert that is made of a first crosslinked polymeric material that comprises repeating units of the first free-radical photoinitiator;
(5) separating the first molding assembly obtained in step (4) into the first male mold half and the female mold half with the molded insert that is adhered onto the central portion of the first molding surface;
(6) dispensing a lens-forming composition in the female mold half with the molded insert adhered thereon in an amount sufficient for filling the lens-molding cavity, wherein the lens forming composition comprises at least one second polymerizable material and a second free-radical photoinitiator;
(7) placing the second male mold half on top of the lens-forming composition in the female mold half and closing the second male mold half and the female mold half to form a second molding assembly comprising the lens-forming composition and the molded insert immersed therein in the lens-molding cavity;
(8) irradiating, with an UV and/or visible light, the lens-forming composition in the lens-molding cavity of the second molding assembly to form an embedded hydrogel lens precursor that comprises a bulk hydrogel material formed from the lens-forming composition and the insert completely or partially embedded in the bulk material, wherein the bulk hydrogel material is a second crosslinked polymeric material that is covalently linked to the first crosslinked polymeric material at repeating units of the first free-radical photoinitiator;
(9) separating the second molding assembly obtained in step (8) into the second male mold half and the female mold half, with the embedded hydrogel lens precursor adhered on a lens-adhered mold half which is one of the female and second male mold halves;
(10) removing the embedded hydrogel lens precursor from the lens-adhered mold half; and
(11) subjecting the embedded hydrogel lens precursor to post-molding processes including a hydration process and one or more other processes selected from the group consisting of extraction, surface treatment, packaging, sterilization, and combinations thereof to form the embedded hydrogel contact lens.