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EP-4304843-B1 - METHOD FOR MAKING PHOTOCHROMIC CONTACT LENSES

EP4304843B1EP 4304843 B1EP4304843 B1EP 4304843B1EP-4304843-B1

Inventors

  • PLAVNIK, MICHELLE
  • BREITKOPF, RICHARD CHARLES
  • ZHANG, Steve Yun
  • BASSAMPOUR, Zahra
  • KOLLURU, CHANDANA

Dates

Publication Date
20260506
Application Date
20220307

Claims (15)

  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 visible-light free-radical photoinitiator, at least one thermal free-radical initiator, at least one first polymerizable material, and at least one photochromic compound, wherein the second polymerizable fluid composition comprises said at least one thermal free-radical initiator and at least one second polymerizable material and is free of any photochromic compound, wherein the first polymerizable fluid composition has a curing time as determined in photo-rheology study using blue light LED's at 450-500 nm and a total irradiance of 0.2-5 mW/cm 2 and a rheometer; by placing a sample of the polymerizable composition between a quartz plate allowing the blue light to pass through and the rheometer, and determining the curing time when the elastic modulus (G') reaches a plateau; (2) obtaining a lens mold, wherein the lens mold comprises a female mold half having a first molding surface defining the anterior surface of a contact lens to be molded and a male mold half having a second molding surface defining the posterior 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 an amount of the first polymerizable fluid composition onto a central zone of the first molding of the female mold half to form a circular layer of the first polymerizable fluid composition, wherein the circular layer has a diameter of about 13.00 mm or less; (4) actinically curing the circular layer of the first polymerizable fluid composition to form a disk having curved surfaces, wherein the step of actinically curing is carried out by irradiating the circular layer of the first polymerizable fluid composition with the visible light at the specified intensity for at least 50% of the curing time; (5) dispensing an amount of the second polymerizable fluid composition over the partially-crosslinked circular layer on the central zone of the first molding surface; (6) closing the female mold half with the male mold half to form a molding assembly comprising the partially crosslinked circular layer immersed in the second polymerizable fluid composition within the mold cavity; (7) thermally curing the second polymerizable fluid composition and the partially-crosslinked circular layer immersed therein in the molding assembly to form an unprocessed hydrogel contact lens (100) having a central photochromic zone (110) that has a diameter of about 13 mm or less, is concentric with the central axis (101) of the unprocessed hydrogel contact lens (100); (8) separating the molding assembly into the male and female mold halves, with the unprocessed hydrogel contact lens (100) adhered onto a lens-adhered mold half which is one of the male and female mold halves; (9) removing the unprocessed hydrogel contact lens (100) from the lens-adhered mold half; and (10) subjecting the unprocessed hydrogel contact lens (100) 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 first and second polymerizable fluid compositions both are capable of forming a non-silicone hydrogel, wherein said at least one first and second polymerizable materials independent of each other are a first monomer mixture comprising (a) at least one first hydrophilic vinylic monomer selected from the group consisting of at least one hydroxyl-containing vinylic monomer, N,N-dimethylarylamide, N-vinylpyrrolidone, at least one methylene-containing pyrrolidone monomer, and combinations thereof, and (b) at least one component selected from the group consisting of at least one non-silicone vinylic crosslinker, a non-silicone hydrophobic vinylic monomer, a UV-absorbing vinylic monomer, and combinations thereof.
  3. The method of claim 2, wherein said at least one first and second polymerizable materials independent of each other comprises at least 50% by weight of at least one hydroxyl-containing vinylic monomer, relative to the total weight of all polymerizable materials present in the first polymerizable fluid composition.
  4. The method of claim 1, wherein the first and second polymerizable fluid compositions both are capable of forming a non-silicone hydrogel, wherein said at least one first and second polymerizable materials independent of each other are a reactive mixture comprising (a) one or more water-soluble non-silicone prepolymers and optionally (b) at least one component selected from the group consisting of a hydrophilic vinylic monomer, a non-silicone vinylic crosslinker, a non-silicone hydrophobic vinylic monomer, a UV-absorbing vinylic monomer, and combinations thereof.
  5. The method of claim 1, wherein the first and second polymerizable fluid compositions both are capable of forming a silicone hydrogel, wherein said at least one first and second polymerizable materials independent of each other are a second monomer mixture comprising (a) at least one silicone-containing vinylic monomer, (b) at least one polysiloxane vinylic crosslinker, at least one non-silicone vinylic crosslinker, or both, (c) at least one second 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 second hydrophilic vinylic monomer comprises at least one hydrophilic (meth)acrylamido monomer having 3 to 8 carbon atoms, at least one hydrophilic (meth)acryloxy monomer, at least one hydrophilic N-vinyl amide monomer, at least one methylene-containing pyrrolidone monomer, at least one vinyl ether monomer, at least one allyl ether monomer, at least one phosphorylcholine-containing vinylic monomer, N-2-hydroxyethyl vinyl carbamate, N-vinyloxycarbonyl-β-alanine, N-vinyloxycarbonyl-α-alanine, or combinations thereof, wherein the sum of the amounts of components (a), (b) and (c) in the second monomer mixture is at least about 60% by weight relative to the total weight of all polymerizable materials present in the second monomer mixture, 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 second monomer mixture comprises at least one polysiloxane vinylic crosslinker of formula (H) in which: d1 is an integer of from 30 to 500 and d2 is an integer of from 1 to 75, provided that d2/d1 is from about 0.035 to about 0.15 (preferably from about 0.040 to about 0.12, even more preferably from about 0.045 to about 0.10); X h1 is O or NR hN in which R hN is hydrogen or C 1 -C 10 -alkyl; R h0 is hydrogen or methyl; R h1 and R h2 independently of each other are a substituted or unsubstituted C 1 -C 10 alkylene divalent radical or a divalent radical of -R h4 -O-R h5 - in which R h4 and R h5 independently of each other are a substituted or unsubstituted C 1 -C 10 alkylene divalent radical; R h3 is a monovalent radical of any one of formula (H-a) to (H-e) k1 is zero or 1; m1 is an integer of 2 to 4; m2 is an integer of 1 to 5; m3 is an integer of 3 to 6; m4 is an integer of 2 to 5; R h6 is hydrogen or methyl; R h7 is a C 2 -C 6 hydrocarbon radical having (m2+1) valencies; R h8 is a C 2 -C 6 hydrocarbon radical having (m4+1) valencies; R h9 is ethyl or hydroxymethyl; R h10 is methyl or hydroxymethyl; R h11 is hydroxyl or methoxy; X h1 is a sulfur linkage of -S- or a teriary amino linkage of -NR h12 - in which R h12 is C 1 -C 4 alkyl, hydroxyethyl, hydroxypropyl, or 2,3-dihydroxypropyl; and X h2 is a linkage of in which R h13 is hydrogen or C 1 -C 10 alkyl.
  7. The method of claim 5 or 6, wherein the second monomer mixture comprises (i) at least one polysiloxane vinylic crosslinker having one sole polydiorganosiloxane segment and two terminal ethylenically-unsaturated groups selected from the group consisting of (meth)acryloyloxy groups, (meth)acryloylamino groups, vinyl carbonate groups, vinylcarbamate groups; and/or (ii) at least one chain-extended polysiloxane vinylic crosslinker having at least two polydiorganosiloxane segment and a covalent linker between each pair of polydiorganosiloxane segments and two terminal ethylenically-unsaturated groups selected from the group consisting of (meth)acryloyloxy groups, (meth)acryloylamino groups, vinyl carbonate groups, vinylcarbamate groups.
  8. The method of any one of claims 5 to 7, wherein said at least one first and second polymerizable materials independent of each other comprise: (i) at least one non-silicone vinylic crosslinker selected from the group consisting of ethyleneglycol di-(meth)acrylate, diethyleneglycol di-(meth)acrylate, triethyleneglycol di-(meth)acrylate, tetraethyleneglycol di-(meth)acrylate, glycerol di-(meth)acrylate, 1,3-propanediol di-(meth)acrylate, 1,3-butanediol di-(meth)acrylate, 1,4-butanediol di-(meth)acrylate, glycerol 1,3-diglycerolate di-(meth)acrylate, ethylenebis[oxy(2-hydroxypropane-1,3-diyl)] di-(meth)acrylate, bis[2-(meth)acryloxyethyl] phosphate, trimethylolpropane di-(meth)acrylate, and 3,4-bis[(meth)acryloyl]tetrahydrofuan, diacrylamide (i.e., N-(1-oxo-2-propenyl)-2-propenamide), dimethacrylamide (i.e., N-(1-oxo-2-methyl-2-propenyl)-2-methyl-2-propenamide), N,N-di(meth)acryloyl-N-methylamine, N,N-di(meth)acryloyl-N-ethylamine, N,N'-methylene bis(meth)acrylamide, N,N'-ethylene bis(meth)acrylamide, N,N'-dihydroxyethylene bis(meth)acrylamide, N,N'-propylene bis(meth)acrylamide, N,N'-2-hydroxypropylene bis(meth)acrylamide, N,N'-2,3-dihydroxybutylene bis(meth)acrylamide, 1,3-bis(meth)acrylamide-propane-2-yl dihydrogen phosphate (i.e., N,N'-2-phophonyloxypropylene bis(meth)acrylamide), piperazine diacrylamide (or 1,4-bis(meth)acryloyl piperazine), tetraethyleneglycol divinyl ether, triethyleneglycol divinyl ether, diethyleneglycol divinyl ether, ethyleneglycol divinyl ether, triallyl isocyanurate, triallyl cyanurate, trimethylopropane trimethacrylate, pentaerythritol tetramethacrylate, bisphenol A dimethacrylate, and combinations thereof; (ii) at least one non-silicone hydrophobic vinylic monomer which comprises at least one C 1 -C 8 alkyl (meth)acrylate, at least one C 5 -C 16 cycloalkyl (meth)acrylate, at least one aryl methacrylate, (meth)acrylonitrile, at least one fluorine-containing acrylic monomer, at least one vinyl alkanoate, at least one vinyloxyalkane, at least one substituted or unsubstituted styrene, vinyl toluene, vinyl chloride, vinylidene chloride, 1-butene, or combinations thereof; (iii) at least one UV-absorbing vinylic monomer; or (iv) combinations thereof.
  9. The method of any one of claims 1 to 8, wherein said at least one first and second polymerizable materials independent of each other comprises at least one UV-absorbing vinylic monomer.
  10. The method of any one of claims 1 to 9, wherein said at least one photochromic compound comprises a naphthopyran, an indeno-fused naphthopyran (i.e., indenonaphthopyran), 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 naphtho-spiropyran, 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.
  11. The method of any one of claims 1 to 10, wherein said at least one photochromic compound is polymerizable and comprises an ethylenicaly-unsaturated group.
  12. The method of claim 11, wherein said at least one photochromic compound is a coupling reaction product of a reactive (meth)acrylamido or (meth)acryloxy monomer having a first reactive functional group and a reactive photochromic compound have a second reactive functional group in the absence or presence of a coupling agent under coupling reaction, wherein the first reactive functional group is selected from the group consisting of -COCl, -COBr, -COOH, -NHR N2 , -NCO, -OH, -CHO, wherein the second reactive functional group is selected from the group consisting of - COOH, -NHR N2 , -NCO, -OH, -SH, -CHO, , or wherein R 0 is hydrogen or methyl and R N2 is hydrogen, a linear or branched C 1 -C 15 alkyl, cyclohexyl, cyclopentyl, a substituted or unsubstituted phenyl, or a substituted- or unsubstituted-phenyl-C 1 -C 6 alkyl, wherein the reactive (meth)acrylamido or (meth)acryloxy monomer is selected from the group consisting of (meth)acryloyl halides (CH 2 =CH-COX or CH 2 =CCH 3 -COX, X= Cl or Br), N-hydroxysuccinimide ester of (meth)acrylic acid, glycidyl (meth)acrylate, isocyanato- C 2 -C 6 alkyl (meth)acrylate, amino-C 2 -C 6 alkyl (meth)acrylamide, C 1 -C 6 alkylamino-C 2 -C 6 alkyl (meth)acrylamide, (meth)acrylic acid, C 2 -C 4 alkylacrylic acid (e.g., ethylacrylic acid, propylacrylic acid, butylacrylic acid), N-2-acrylamidoglycolic acid, 3-(acryloylxy)propanoic acid, C 2 -C 6 hydroxylalkyl (meth)acrylate, C 2 -C 6 hydroxyalkyl (meth)acrylamide, an azlactone-containing vinylic monomer, an aziridinyl C 1 -C 12 alkyl (meth)acrylate, acrolein, methacrolein, crotonaldehyde, and combinations thereof.
  13. The method of any one of claims 1 to 12, wherein said at least one first and second polymerizable materials independent of each other comprises at least one polymerizable UV/HEVL-absorbing compound.
  14. The method of any one of claims 1 to 13, wherein said at least one visible light free radical initiator comprises a benzoylphosphine initiator and/or an acylgermanium photoinitiator.
  15. The method of claim 14, wherein the visible light is a visible light in a region of from 420 nm to 500 nm.

Description

This invention is related to a method for producing contact lenses, in particular, silicone hydrogel contact lenses, having a central photochromic zone. This invention also provides contact lenses made according to a method of the invention. BACKGROUND Conventionally, UV-absorbing compounds have been incorporated into contact lenses to make UV-absorbing contact lenses to protect eyes from UV-radiations. Recently, there have been proposed various photochromic contact lenses for protecting eyes from UV-radiations (see, e.g., U.S. Pat. Nos. 4681412, 6017121, 6174464, 6224945, 7261844, 7368072, 7556750, 7560056, 7584630, 7641337, 7999989, 8158037, 8697770, 8741188, 9052438, 9097916, 9377569, 9465234, 9904074, 10197707). Those proposed photochromic contact lenses contains photochromic compounds which are capable of undergoing a reversible color change, e.g., from "clear" to blue or other color, upon exposure to UV/HEVL radiation. Typically, photochromic contact lenses can be obtained by adding a photochromic compound in a polymerizable composition (i.e., lens formulation) for forming the contact lenses and then by curing the polymerizable composition in contact lens molds according to a cast-molding lens manufacturing process. A conventional cast-molding lens manufacturing process comprises: one single-step curing (polymerizing) of one single polymerizable composition (lens formulation) within disposable plastic molds typically consisting of two single-use mold halves; opening molds; optionally but preferably delensing (i.e., removing cast-molded lenses from the molds); and being subjected to various post-molding processes including extraction, hydration, packaging, and sterilization, etc. However, photochromic contact lenses obtained according to such a conventional cast-molding process have photochromic compound incorporated uniformly within the polymer matrix of the photochromic contact lenses and are, from edge-to-edge, capable of undergoing a reversible color change upon exposure to UV/HEVL-radiation. Such photochromic contact lenses are not desirable for cosmetic reasons. It would be desirable to produce a photochromic contact lens that changes color only in the central pupil region. U.S. Pat. Nos. 7368072, 7560056, 8697770 and 9904074 disclose methods for making photochromic contact lenses only the central pupillary regions of which can undergo a reversible color change upon exposure to UV/HEVL-radiation. Those methods comprise steps of: dosing a photochromic lens-forming composition onto the central region of the molding surface of a mold half and followed by adding a clear lens-forming composition on the top of the photochromic lens-forming composition, wherein the photochromic lens-forming composition has a viscosity much higher than the clear lens-forming composition; mating with the other mold half to form a cavity with the photochromic and clear lens-forming compositions therewithin; and curing the photochromic and clear lens-forming compositions within the cavity of the mold to form the photochromic contact lens. However, handling and dosing of a high viscous photochromic lens-forming composition could be challenging in a production environment. US2016/313571 A1 according to its abstract discloses a molded contact lens comprising a stiffer optic zone relative to the peripheral zone of the contact lens provides an optical element for correcting astigmatism without the need for or substantially minimizing the need for the correction of rotational misalignment. The higher elastic modulus optic zone vaults over the cornea thereby allowing a tear lens to form. The tear lens follows or assumes the shape of the back surface of the contact lens. The combination of the tear lens and the optical zone provide an optical element for correction of refractive error. Therefore, there is still a need for a method for making photochromic contact lenses only the central pupillary regions of which can undergo a reversible color change upon exposure to UV/HEVL-radiation. SUMMARY The invention, in some aspects, provides 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 visible-light free-radical photoinitiator, at least one thermal free-radical initiator, at least one first polymerizable material, and at least one photochromic compound, wherein the second polymerizable fluid composition comprises said at least one thermal free-radical initiator and at least one second polymerizable material and is free of any photochromic compound, wherein the first polymerizable fluid composition has a curing time as determined in photo-rheology study using a visible light at a specified intensity; (2) obtaining a lens mold, wherein the lens mold comprises a female mold half having a first molding surface defining the anterior surface of a conta