Method for making embedded hydrogel contact lenses
AssigneeAlcon Inc.
InventorsRichard Charles Breitkopf, Zahra Bassampour, Chandana Kolluru, Steve Yun Zhang
Life of this patent
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Abstract
The invention relates to a method for producing embedded hydrogel contact lenses each having a magnetized insert that comprises magnetic particles and is centrally embedded in the bulk hydrogel material of the embedded hydrogel contact lens. During molding, a magnetized insert can be centered and held in position in a lens mold by using a magnet placed below the lens mold. The invention also relates to an embedded hydrogel contact lens produced from a method of the invention.
Claims19
A method for producing embedded hydrogel contact lenses, comprising the steps of:
- (1) obtaining a magnetized insert which comprises a front surface, an opposite back surface and a diameter up to about 13.0 mm, wherein the insert is made of a polymeric material and comprises magnetic particles;
- (2) obtaining a lens mold, wherein the lens mold comprises a female mold half having a first molding surface and a male mold half having a second molding surface, wherein the female and male mold halves are configured to receive each other such that a mold cavity is formed between the first and second molding surfaces when the mold is closed;
- (3) in no particular order, placing the magnetized insert in the lens mold and introducing a lens-forming composition in the lens mold, wherein the magnetized insert is immersed in the lens-forming composition in the lens mold and centered and held in position in the lens mold by using a magnet which is place below the lens mold;
- (4) curing the lens-forming composition in the lens mold while holding the magnetized insert centered in the lens mold by the magnet to form an unprocessed embedded hydrogel contact lens that comprise a bulk hydrogel material formed from the lens-forming composition and the magnetized insert embedded in the bulk hydrogel material and centered in the unprocessed embedded hydrogel contact lens;
- (5) separating the lens mold obtained in step (4) into the male and female mold halves, with the unprocessed embedded hydrogel contact lens adhered on a lens-adhered mold half which is one of the male and female mold halves;
- (6) removing the unprocessed embedded hydrogel contact lens from the lens-adhered mold half (preferably before the unprocessed embedded hydrogel contact lens is contact with water or any liquid);
- and
- (7) subjecting the unprocessed embedded hydrogel contact lens 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.
An embedded hydrogel contact lens, comprising:
- an anterior surface, an opposite posterior surface, a bulk hydrogel material, and a magnetized insert embedded in the bulk hydrogel material,
- wherein the magnetized insert is made of a polymeric material and comprises magnetic particles, wherein the magnetized insert has a front surface, an opposite back surface and a diameter up to about 13.0 mm, wherein the magnetized insert is located in a central portion of the embedded hydrogel contact lens, wherein the embedded hydrogel contact lens is not susceptible to delamination as demonstrated by being free of bubble that can be observed under microscopy at interfaces between the insert and the bulk material within the embedded silicone hydrogel contact lens after being autoclaved in a packaging solution in a sealed package, wherein the packaging solution is a buffered saline having a pH of 7.1±0.2.
Dependencies are inferred from the claim text.