Method for making photochromic contact lenses

Patent metadata

Field	Value
Publication number	US-11833771-B2
Application number	US-202217710248-A
Country	US
Kind code	B2
Filing date	Mar 31, 2022
Priority date	Apr 1, 2021
Publication date	Dec 5, 2023
Grant date	Dec 5, 2023

Abstract

Described herein is a method for producing a contact lens comprising a central photochromic zone that has a diameter of about 13 mm or less and is concentric with the central axis of the contact lens. The method comprises: applying, in the center of the molding surface of a male mold half, a drop (having a volume of about 5 μL or less) of a first polymerizable fluid composition containing at least one photochromic compound and a relatively-high molecular weight polysiloxane vinylic crosslinker for increasing the viscosity and adhesion on the molding surface of the male mold half; dosing a second polymerizable fluid composition in a female mold hald; closing the female mold hald with the male mold half with the drop thereon to form a molding assembly; and curing the second polymerizable fluid composition and the drop of the first polymerizable fluid composition in the molding assembly.

First claim

What is claimed is:

1. A method for producing hydrogel contact lenses, comprising the steps of:
(1) obtain a first polymerizable fluid composition and a second polymerizable fluid composition, wherein the first polymerizable fluid composition comprises at least one first free-radical initiator, at least one first polymerizable material, and at least one photochromic compound, wherein said at least one first polymerizable material comprises at least one first polysiloxane vinylic crosslinker that has a weight-averaged molecular weight of about 5000 Daltons or higher and is present in the first polymerizable composition in an amount of about 40% by weight or more, wherein the second polymerizable fluid composition comprises said at least one second free-radical initiator and at least one second polymerizable material and is free of any photochromic compound;
(2) obtaining a lens mold, wherein the lens mold comprises a male mold half having a first molding surface defining the posterior surface of a contact lens to be molded and a female mold half having a second molding surface defining the anterior surface of the contact lens to be molded, 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) applying a drop of the first polymerizable fluid composition onto the geometrial center of the first molding surface of the male mold half, wherein the drop has a volume of about 5 μL or less;
(4) dispensing an amount of the second polymerizable fluid composition on the second molding surface of the female mold half;
(5) closing the female mold half with the male mold half having the drop adhered thereon to form a molding assembly comprising the second polymerizable composition and the drop of the first polymerizable composition within the mold cavity;
(6) curing the second polymerizable fluid composition and the drop of the first polymerizable composition to form an unprocessed silicone hydrogel contact lens having a central photochromic zone that has a diameter of about 13 mm or less, is concentric with the central axis of the unprocessed silicone hydrogel contact lens;
(7) separating the molding assembly into the male and female mold halves, with the unprocessed silicone hydrogel contact lens adhered onto a lens-adhered mold half which is one of the male and female mold halves;
(8) removing the unprocessed silicone hydrogel contact lens from the lens-adhered mold half; and
(9) subjecting the unprocessed silicone 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.

2. The method of claim 1 , wherein the step of (6) curing is carried out thermally, wherein said at least one first and second free-radical initiators comprise a thermal free-radical initiator.

3. The method of claim 1 , wherein the step of (6) curing is carried out actinically, wherein said at least one first and second free-radical initiators comprise a free-radical photoinitiator.

4. The method of claim 1 , wherein the first polymerizable fluid composition further comprises at least one visible light free-radical photoinitiator, wherein the drop of the first polymerizable fluid composition is irradiated with a visible light for about 10 second or less before dispensing the second polymerizable fluid composition.

5. The method of claim 1 , wherein said at least one first and second polymerizable materials independent of each other comprises: (a) at least one silicone-containing vinylic monomer, (b) at least one second polysiloxane vinylic crosslinker, at least one non-silicone vinylic crosslinker, or combinations thereof, (c) at least one hydrophilic vinylic monomer, and optionally (d) at least one component selected from the group consisting of a non-silicone hydrophobic vinylic monomer, a UV-absorbing vinylic monomer, and combinations thereof, wherein said at least one hydrophilic vinylic monomer comprises: (i) at least one hydrophilic (meth)acrylamido monomer having 3 to 8 carbon atoms; (ii) at least one hydrophilic (meth)acryloxy monomer; (iii) at least one hydrophilic N-vinyl amide monomer; or (iv) combinations thereof;
wherein said at least one silicone-containing vinylic monomer comprises: (i) at least one silicone-containing vinylic monomer containing a tris(trialkylsiloxy)silyl group and one sole ethylenically-unsaturated group selected from the group consisting of a (meth)acryloyloxy group, a (meth)acryloylamino group, a vinyl carbonate group, and a vinylcarbamate group; (ii) at least one silicone-containing vinylic monomer containing a bis(trialkylsilyloxy)-alkylsilyl group and one sole ethylenically-unsaturated group selected from the group consisting of a (meth)acryloyloxy group, a (meth)acryloylamino group, a vinyl carbonate group, and a vinylcarbamate group; (iii) at least silicone-containing vinylic monomer containing a) one sole ethylenically-unsaturated group selected from the group consisting of a (meth)acryloyloxy group, a (meth)acryloylamino group, a vinyl carbonate group, and a vinylcarbamate group and b) a polysiloxane chain having 2 to 30 siloxane units and terminated with an alkyl, hydroxyalkyl or methoxyalkyl group; or (iv) combinations thereof.

6. The method of claim 5 , wherein the sum of the amounts of components (a), (b) and (c) in the monomer mixture is at least about 60% by weight relative to the total weight of all polymerizable materials present in the monomer mixture.

7. The method of claim 6 , wherein said at least one first and second polymerizable materials independent of each other comprise at least one second polysiloxane vinylic crosslinker.

8. The method of claim 6 , wherein said at least one first and second polymerizable materials independent of each other comprises: at least one non-silicone vinylic crosslinker; at least one non-silicone hydrophobic vinylic monomer; at least one UV-aborbing vinylic monomer; or combinations thereof.

9. The method of claim 8 , wherein said at least one photochromic compound comprises a naphthopyran, an indeno-fused naphthopyran, a heterocyclic ring-fused naphthopyrian, a benzopyran, a phenanthropyran, a quinopyran, a quinolinopyran, a fluoroanthenopyran, an anthracene-fused pyran, a tetracene-fused pyran, a spiro(benzindoline) naphthopyran, a spiro(indoline)naphthopyran, a spiro(indoline)benzopyran, a spiro(indoline)quinopyran, a spiro(indoline)pyran, a naphthoxazine, a spirobenzopyran, a spirobenzothiopyran, a naphthacenedione, a benzoxazine, a spirooxazine, a naphthoxazine, a spiro(benzindoline)naphthoxazine, a spiro(indoline)naphthoxazine, a spiro(indoline)pyrido-benzoxazine, a spiro(indoline)benzoxazine, a spiro(benzindoline) benzoxazine, a spiro(benzindoline)pyridobenzoxazine, a spiro(indoline) fluoranthenoxazine, a spiro(indoline)-quinoxazine, a spiropiperidine-naphthopyran, a piro(indoline)pyronobenzoxazinone, a benzospiropyran, a naphthospiropyran, a spirobenzoxazine-pyrrolopyridine, a spironaphthoxazine-pyrrolopyrridine, a spiro-oxazepin-benzoxazine, a spiro-oxazepin-naphthoxazine, a spiro(indoline) benzothiazoloxazine, a spiro(indoline)benzopyrroloxazine, a spiro(indoline)quinazolino-oxazine, a spiro(indoline)-anthracenobenzoxazine, a benzofurobenzopyran, a benzothienobenzopyran, a naphthofurobenzopyran, a benzopyrano-fused naphthopyran, a spiro(isoindoline)-naphthoxazine, a spiro(isoindoline)benzoxazine, or a mixture thereof.

10. The method of claim 9 , wherein said at least one photochromic compound is polymerizable and comprises an ethylenicaly-unsaturated group.

Assignees

• Alcon Inc

Inventors

• Chang Yuan
• Ge Junhao
• Zhang Steve Yun
• Plavnik Michelle
• Zheng Yang
• Cheng Jing
• Kumi Augustine Twum

Classifications

• B29D11/00134 Primary

  Curing of the contact lens material · CPC title

• C08L83/14

  in which at least two but not all the silicon atoms are connected by linkages other than oxygen atoms (C08L83/10 takes precedence) · CPC title

• G02C7/04

  Contact lenses for the eyes (disinfection or sterilisation of contact lenses A61L12/00) · CPC title

• G02C7/102

  Photochromic filters · CPC title

• B29K2083/00

  Use of polymers having silicon, with or without sulfur, nitrogen, oxygen, or carbon only, in the main chain, as moulding material · CPC title